[Federal Register Volume 67, Number 85 (Thursday, May 2, 2002)]
[Rules and Regulations]
[Pages 22296-22314]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 02-10764]
[[Page 22295]]
-----------------------------------------------------------------------
Part IV
Department of Health and Human Services
-----------------------------------------------------------------------
42 CFR Parts 81 and 82
Guidelines for Determining the Probability of Causation and Methods for
Radiation Dose Reconstruction Under the Employees Occupational Illness
Compensation Program Act of 2000; Final Rules
Federal Register / Vol. 67 , No. 85 / Thursday, May 2, 2002 / Rules
and Regulations
[[Page 22296]]
-----------------------------------------------------------------------
DEPARTMENT OF HEALTH AND HUMAN SERVICES
42 CFR Part 81
RIN 0920-ZA01
Guidelines for Determining the Probability of Causation Under the
Energy Employees Occupational Illness Compensation Program Act of 2000;
Final Rule
AGENCY: Department of Health and Human Services.
ACTION: Final rule.
-----------------------------------------------------------------------
SUMMARY: This rule implements select provisions of the Energy Employees
Occupational Illness Compensation Program Act of 2000 (``EEOICPA'' or
``Act''). The Act requires the promulgation of guidelines, in the form
of regulations, for determining whether an individual with cancer shall
be found, ``at least as likely as not,'' to have sustained that cancer
from exposure to ionizing radiation in the performance of duty for
nuclear weapons production programs of the Department of Energy and its
predecessor agencies. The guidelines will be applied by the U.S.
Department of Labor, which is responsible for determining whether to
award compensation to individuals seeking federal compensation under
the Act.
DATES: Effective Date: This final rule is effective May 2, 2002.
FOR FURTHER INFORMATION CONTACT: Larry Elliott, Director, Office of
Compensation Analysis and Support, National Institute for Occupational
Safety and Health, 4676 Columbia Parkway, MS-R45, Cincinnati, OH 45226,
Telephone 513-841-4498 (this is not a toll-free number). Information
requests can also be submitted by e-mail to [email protected]
SUPPLEMENTARY INFORMATION:
I. Background
A. Statutory Authority
The Energy Employees Occupational Illness Compensation Program Act
of 2000(``EEOICPA''), 42 U.S.C. 7384-7385 [1994, supp. 2001],
established a compensation program to provide a lump sum payment of
$150,000 and medical benefits as compensation to covered employees
suffering from designated illnesses (i.e. cancer resulting from
radiation exposure, chronic beryllium disease, or silicosis) incurred
as a result of their exposures while in the performance of duty for the
Department of Energy (``DOE'') and certain of its vendors, contractors,
and subcontractors. This legislation also provided for payment of
compensation to certain survivors of covered employees.
EEOICPA instructed the President to designate one or more federal
agencies to carry out the compensation program. Pursuant to this
statutory provision, the President issued Executive Order 13179 titled
Providing Compensation to America's Nuclear Weapons Workers, which
assigned primary responsibility for administering the compensation
program to the Department of Labor (``DOL''). 65 FR 77,487 (Dec. 7,
2000). DOL published an interim final rule governing its administration
of EEOICPA on May 25, 2001 (20 CFR Parts 1 and 30).
The Executive Order directed the Department of Health and Human
Services (``HHS'') to perform several technical and policymaking roles
in support of the DOL program:
(1) HHS is to develop guidelines to be used by DOL to assess the
likelihood that an employee with cancer developed that cancer as a
result of exposure to radiation in performing his or her duties at a
DOE facility or Atomic Weapons Employer (``AWE'') facility. These
``Probability of Causation'' guidelines are the subject of this final
rule, and were initially proposed for public comment in a notice of
proposed rulemaking published on October 5, 2001.
(2) HHS is also to establish methods to estimate radiation doses
(``dose reconstruction'') for certain individuals with cancer applying
for benefits under the DOL program, and HHS is to implement these
methods in a program of dose reconstruction for EEOICPA claims. HHS
published these methods as an interim final rule under 42 CFR part 82
on October 5, 2001, and is publishing them as a final rule
simultaneously in this issue of the Federal Register. HHS is presently
applying these methods to conduct the program of dose reconstruction
required by EEOICPA.
(3) HHS is to staff the Advisory Board on Radiation and Worker
Health and provide it with administrative and other necessary support
services. The Board, a federal advisory committee, was appointed by the
President in November 2001. It was first convened on January 22, 2001,
and is advising HHS in implementing its roles under EEOICPA described
here.
(4) Finally, HHS is to develop and apply procedures for considering
petitions by classes of employees at DOE or AWE facilities seeking to
be added to the Special Exposure Cohort established under EEOICPA.
Employees included in the Special Exposure Cohort who have a specified
cancer and meet other conditions, as defined by EEOICPA and DOL
regulations (20 CFR 30), qualify for compensation under EEOICPA. HHS
has developed proposed procedures for considering Special Exposure
Cohort petitions which will be published soon in the Federal Register.
HHS will obtain public comment and a review by the Advisory Board on
Radiation and Worker Health before these procedures are made final and
implemented.
As provided for under 42 U.S.C. 7384p, HHS is implementing its
responsibilities with the assistance of the National Institute for
Occupational Safety and Health (``NIOSH''), an institute of the Centers
for Disease Control and Prevention, HHS.
B. Purpose of Probability of Causation Guidelines
Under EEOICPA, a covered employee seeking compensation for cancer,
other than as a member of the Special Exposure Cohort seeking
compensation for a specified cancer, is eligible for compensation only
if DOL determines that the cancer was ``at least as likely as not'' (a
50% or greater probability) caused by radiation doses incurred in the
performance of duty while working for DOE and/or an atomic weapons
employer (AWE) facility. These guidelines provide DOL with the
procedure to make these determinations, and specify the information DOL
will use.
HHS notes that EEOICPA does not authorize the establishment of new
radiation protection standards through the promulgation of these
guidelines, and these guidelines do not constitute such new standards.
C. Statutory Requirements for Probability of Causation Guidelines
EEOICPA has several general requirements concerning the development
of these guidelines. It requires the guidelines provide for
determinations that are based on the radiation dose received by the
employee, incorporating the methods of dose reconstruction to be
established by HHS. It requires determinations be based on the upper 99
percent confidence interval of the probability of causation in the
radioepidemiological tables published under section 7(b) of the Orphan
Drug Act (42 U.S.C. 241 note), as such tables may be updated. EEOICPA
also requires HHS to consider the type of cancer, past health-related
activities, the risk of developing a radiation-related cancer from
workplace exposure, and other relevant factors. 42 U.S.C. 7384n(c). It
is also important to
[[Page 22297]]
note EEOICPA does not include a requirement limiting the types of
cancers to be considered radiogenic for these guidelines.
D. Understanding Probability of Causation
Probability of Causation is a technical term generally meaning an
estimate of the percentage of cases of illness caused by a health
hazard among a group of persons exposed to the hazard. This estimate is
used in compensation programs as an estimate of the probability or
likelihood that the illness of an individual member of that group was
caused by exposure to the health hazard. Other terms for this concept
include ``assigned share'' and ``attributable risk percent'.
In this rule, the potential hazard is ionizing radiation to which
U.S. nuclear weapons workers were exposed in the performance of duty;
the illnesses are specific types of cancer. The probability of
causation (PC) is calculated as the risk of cancer attributable to
radiation exposure (RadRisk) divided by the sum of the baseline risk of
cancer to the general population (BasRisk) plus the risk attributable
to the radiation exposure, then multiplied by 100 percent, as follows:
[GRAPHIC] [TIFF OMITTED] TR02MY02.011
This calculation provides a percentage estimate between 0 and 100
percent, where 0 would mean 0 likelihood that radiation caused the
cancer and 100 would mean 100 percent certainty that radiation caused
the cancer.
Scientists evaluate the likelihood that radiation caused cancer in
a worker by using medical and scientific knowledge about the
relationship between specific types and levels of radiation dose and
the frequency of cancers in exposed populations. Simply explained, if
research determines that a specific type of cancer occurs more
frequently among a population exposed to a higher level of radiation
than a comparable population (a population with less radiation exposure
but similar in age, gender, and other factors that have a role in
health), and if the radiation exposure levels are known in the two
populations, then it is possible to estimate the proportion of cancers
in the exposed population that may have been caused by a given level of
radiation.
If scientists consider this research sufficient and of reasonable
quality, they can then translate the findings into a series of
mathematical equations that estimate how much the risk of cancer in a
population would increase as the dose of radiation incurred by that
population increases. The series of equations, known as a dose-response
or quantitative risk assessment model, may also take into account other
health factors potentially related to cancer risk, such as gender,
smoking history, age at exposure (to radiation), and time since
exposure. The risk models can then be applied as an imperfect but
reasonable approach to determine the likelihood that the cancer of an
individual worker was caused by his or her radiation dose.
E. Development and Use of the RadioEpidemiological Tables and
Interactive RadioEpidemiological Program
In 1985, in response to a congressional mandate in the Orphan Drug
Act, a panel established by the National Institutes of Health developed
a set of Radioepidemiological Tables. The tables serve as a reference
tool providing probability of causation estimates for individuals with
cancer who were exposed to ionizing radiation. Use of the tables
requires information about the person's dose, gender, age at exposure,
date of cancer diagnosis and other relevant factors. The tables are
used by the Department of Veterans Affairs (DVA) to make compensation
decisions for veterans with cancer who were exposed in the performance
of duty to radiation from atomic weapon detonations.
The primary source of data for the 1985 tables is research on
cancer-related deaths occurring among Japanese atomic bomb survivors
from World War II.
The 1985 tables are presently being updated by the National Cancer
Institute (NCI) and the Centers for Disease Control and
Prevention1 to incorporate progress in research on the
relationship between radiation and cancer risk. The draft update has
been reviewed by the National Research Council 2 and by
NIOSH. DOL will employ the updated version of the tables, with
modifications important to claims under EEOICPA (described below under
``G'' and in response to public comments under ``II''), as a basis for
determining probability of causation for employees covered under
EEOICPA.
---------------------------------------------------------------------------
\1\ Draft Report of the NCI-CDC Working Group to Revise the 1985
NIH Radioepidemiological Tables, May 31, 2000.
\2\ A Review of the Draft Report of the NCI-CDC Working Group to
Revise the ``1985 Radioepidemiological Tables'', National Research
Council.
---------------------------------------------------------------------------
A major scientific change achieved by this update is the use of
risk models developed from data on the occurrence of cancers (cases of
illness) rather than the occurrence of cancer deaths among Japanese
atomic bomb survivors. The risk models are further improved by being
based on more current data as well. Many more cancers have been modeled
in the revised report. The new risk models also take into account
factors that modify the effect of radiation on cancer, related to the
type of radiation dose, the amount of dose, and the timing of the dose.
A major technological change accompanying this update, which
represents a scientific improvement, is the production of a computer
software program for calculating probability of causation. This
software program, named the Interactive RadioEpidemiological Program
(IREP), allows the user to apply the NCI risk models directly to data
on an individual employee. This makes it possible to estimate
probability of causation using better quantitative methods than could
be incorporated into printed tables. In particular, IREP allows the
user to take into account uncertainty concerning the information being
used to estimate probability of causation. There typically is
uncertainty about the radiation dose levels to which a person has been
exposed, as well as uncertainty relating levels of dose received to
levels of cancer risk observed in study populations.
Accounting for uncertainty is important because it can have a large
effect on the probability of causation estimates. DVA, in their use of
the 1985 Radioepidemiological Tables, uses the probability of causation
estimates found in the tables at the upper 99 percent credibility
limit. This means when DVA determines whether the cancer of a veteran
was more likely than not caused by radiation, they use the estimate
that is 99 percent certain to be greater than the probability that
would be calculated if the information on dose and the risk model were
perfectly accurate. Similarly, these HHS guidelines, as required by
EEOICPA, will use the upper 99 percent credibility limit to determine
whether the cancers of employees are at least as likely as not caused
by their occupational radiation doses. 42 U.S.C. 7384n(c)(3)(A). This
will help minimize the possibility of denying compensation to claimants
under EEOICPA for those employees with cancers likely to have been
caused by occupational radiation exposures.
F. Use of IREP for Energy Employees
The risk models developed by NCI and CDC for IREP provide the
primary basis for developing guidelines for estimating probability of
causation under EEOICPA. They directly address 33 cancers and most
types of radiation
[[Page 22298]]
exposure relevant to employees covered by EEOICPA. These models take
into account the employee's cancer type, year of birth, year of cancer
diagnosis, and exposure information such as years of exposure, as well
as the dose received from gamma radiation, x rays, alpha radiation,
beta radiation, and neutrons during each year. Also, the risk model for
lung cancer takes into account smoking history and the risk model for
skin cancer takes into account race/ethnicity. None of the risk models
explicitly accounts for exposure to other occupational, environmental,
or dietary carcinogens. Models accounting for these factors have not
been developed and may not be possible to develop based on existing
research. Moreover, DOL could not consistently or efficiently obtain
the data required to make use of such models.
IREP models do not specifically include cancers as defined in their
early stages: carcinoma in situ (CIS). These lesions are becoming more
frequently diagnosed, as the use of cancer screening tools, such as
mammography, have increased in the general population. The risk factors
and treatment for CIS are frequently similar to those for malignant
neoplasms, and, while controversial, there is growing evidence that CIS
represents the earliest detectable phase of malignancy.3
Therefore, for determining compensation under EEOICPA, HHS requires
that CIS be treated as a malignant neoplasm of the specified site.
---------------------------------------------------------------------------
\3\ Kerlikowske, K, J Barclay, D Grady, EA Sickles, and V
Ernster. ``Comparison of risk factors for ductal carcinoma in situ
and invasive breast cancer.'' J. Natl. Canc. Inst. 89:76-82, 1997.
Grippo, PJ, and EP Sandgren. ``Highly invasive transitional cell
carcinoma of the bladder in a simian virus 40 T-antigen transgenic
mouse model.'' Am. J. Pathol. 157:805-813, 2000.
Correa P, ``Morphology and natural history of cancer
precursors'' Chapter 4 in: Cancer Epidemiology and Prevention, 2nd
Edition, D Schottenfeld and JF Fraumeni, Jr, eds. New York: Oxford
University Press, 1996.
---------------------------------------------------------------------------
Cancers identified by their secondary sites (sites to which a
malignant cancer has spread), when the primary site is unknown, raise
another issue for the application of IREP. This situation will most
commonly arise when death certificate information is the primary source
of a cancer diagnosis. It is accepted in medicine that cancer-causing
agents such as ionizing radiation produce primary cancers. This means,
in a case in which the primary site of cancer is unknown, the primary
site must be established by inference to estimate probability of
causation.
HHS establishes such assignments in these guidelines, based on an
evaluation of the relationship between primary and secondary cancer
sites using the National Center for Health Statistics (NCHS) Mortality
Database for years 1995-1997. Because national cancer incidence
databases (e.g., the National Cancer Institute's Surveillance,
Epidemiology and End Results program) do not contain information about
sites of metastasis, the NCHS database is the best available data
source at this time to assign the primary site(s) most likely to have
caused the spread of cancer to a known secondary site. For each
secondary cancer, HHS identified the set of primary cancers producing
approximately 75% of that secondary cancer among the U.S. population
(males and females were considered separately). The sets are tabulated
in this rule (Table 1). DOL will determine the final assignment of a
primary cancer site for an individual claim on a case-by-case basis, as
the site among possible primary sites which results in the highest
probability of causation estimate.
Employees diagnosed with two or more primary cancers also raise a
special issue for determining probability of causation. Even under the
assumption that the biological mechanisms by which each cancer is
caused are unrelated, uncertainty estimates about the level of
radiation delivered to each cancer site will be related. While fully
understanding this situation requires statistical training, the
consequence has simple but important implications. Under this rule,
instead of determining the probability that each cancer was caused by
radiation independently, DOL will perform an additional statistical
procedure following the use of IREP to determine the probability that
at least one of the cancers was caused by the radiation. This approach
is important to the claimant because it would determine a higher
probability of causation than would be determined for either cancer
individually.
G. Limitations of IREP for Energy Employees
NCI is developing IREP to serve the needs of DVA in deciding cancer
compensation claims for veterans. This means IREP has to be adapted in
various ways to meet the needs of DOL, because the radiation exposure
experience of employees covered by EEOICPA differs substantially.
Some employees covered by EEOICPA were exposed to radon and other
sources of high linear energy transfer (LET) radiation. This type of
radiation exposure has unique properties affecting cancer risk, which
are not addressed in the risk models included in IREP. Specifically,
the IREP risk models do not account for a possible inverse dose-rate
effect for high-LET radiation exposures. This effect means at any
particular dose level, especially higher dose levels, a dose of high
LET radiation incurred gradually over time is more likely to cause
cancer than the same total dose incurred quickly or at once. A
substantial body of research supports this finding, including studies
of uranium miners,4 patients exposed to bone-seeking radium
alpha particles,5 and research on the cancer effects of high
LET radiation in animals.6 Because high-LET radiation is an
important type of radiation exposure among employees covered by
EEOICPA, NIOSH has modified IREP to include uncertainty associated with
the assumption of an inverse dose-rate effect for these exposures.
---------------------------------------------------------------------------
\4\ Hornung RW, Meinhardt TJ. Quantitative risk assessment of
lung cancer in U.S. uranium miners. Health Phys 52: 417-430, 1987.
Lubin JH, Boice JD Jr, Edling C, et al. Radon-exposed
underground miners and the inverse dose-rate (protraction
enhancement) effects. Health Phys 69:494-550, 1995.
\5\ Mays CW, Spiess H. Bone sarcomas in patients given radium-
224. In: Radiation Carcinogenesis: Epidemiology and Biological
Significance. Boice JD Jr, Fraumeni JF Jr (eds): New York: Raven
Press, pp 241-252, 1984.
\6\ Luebeck EG, Curtis SB, Cross FT, Moolgavkar SH. Two-stage
model of radon-induced malignant lung tumors in rats: effects of
cell killing. Radiat. Res. 145:163-173, 1996.
Hall EJ, Miller RC, Brenner DJ. Neoplastic transformation and
the inverse dose-rate effect for neutrons. Radiat. Res. 128 (Suppl):
S75-S80, 1991.
---------------------------------------------------------------------------
The DOE workforce has been exposed to various types of neutron
energies and these exposures are frequently documented in the worker's
dosimetry records. The relative biological effectiveness (RBE) of
radiation exposure, a factor in cancer risk models that accounts for
the differing level of cancer risk associated with different forms of
radiation, varies as a function of neutron energy.7 This
variation in RBE related to differing neutron energy is not accounted
for in the current version of IREP, which contains a single neutron RBE
distribution. Therefore, NIOSH has modified IREP for DOE workers to
include different RBE distributions for neutrons of various energies.
---------------------------------------------------------------------------
\7\ International Commission on Radiological Protection (ICRP)
60: ``1990 Recommendations of the International Commission on
Radiological Protection.'' Ann. ICRP 21 (1-3): 1-201.
---------------------------------------------------------------------------
The currently public draft of IREP does not incorporate a unique
lung cancer model for radon exposure, which is an important exposure
for some workers covered under EEOICPA. Using epidemiologic evidence on
the lung carcinogenicity of radon exposures, NCI
[[Page 22299]]
has incorporated a lung cancer model for radon exposures into IREP. The
data source for this model is the analysis conducted by the federal
Radiation Exposure Compensation Act Committee.8
---------------------------------------------------------------------------
\8\ Final Report of the Radiation Exposure Compensation Act
Committee, submitted to the Human Radiation Interagency Working
Group, July 1996 (Appendix A), 30 pp (plus Figures).
---------------------------------------------------------------------------
NIOSH has changed IREP to modify an assumption for non-leukemia
cancers that low-level acute radiation doses (defined in IREP as doses
between 3 and 30 cSv) cause less risk, per unit of dose, than higher
level acute doses. NIOSH will use an uncertainty distribution for the
dose and dose rate effectiveness factor (DDREF) that more heavily
weights a DDREF of one, reducing the distinction in risk effects for
low-level acute doses. A recent study of the Japanese atomic bomb
survivors supports this change.9
---------------------------------------------------------------------------
\9\ Pierce DA and Preston DL ``Radiation-related cancer risks at
low doses among atomic bomb survivors.'' Radiat. Res. 154:178-186,
2000.
---------------------------------------------------------------------------
Additionally, some employees covered by EEOICPA were required, as a
condition of employment, to undergo routine medical screening with x
rays. The dose resulting from these x rays will be included in their
dose reconstruction. This required NIOSH to add to IREP an RBE
distribution appropriate to the low-energy form of radiation produced
from some of these x rays. 10
---------------------------------------------------------------------------
\10\ ICRU Report 40: The quality factor in radiation protection.
Internat. Commission on Radiat. Units and Meas., 33 pp, 1986.
Hall EJ. ``Linear energy transfer and relative biological
effectiveness'' Chapter 9 in Radiobiology for the Radiobiologist,
4th Edition. Philadelphia: J.B. Lippincott, 1994.
---------------------------------------------------------------------------
Research has found bone cancer risk substantially and significantly
elevated among animals and humans exposed to certain forms of high-LET
radiation. 11 Although Japanese A-bomb survivor risk models
for bone cancer have been used for a plutonium risk assessment,
12 they are based on highly unstable risk models. Therefore,
NIOSH is using in IREP the risk model recommended in the NCI-IREP
documentation, which is based on all residual cancers, including bone.
---------------------------------------------------------------------------
\11\ International Agency for Research on Cancer (IARC). IARC
Monographs on the Evaluation of Carcinogenic Risks to Humans, Vol.
78 Ionizing Radiation, Part 2: Some Internally Deposited
Radionuclides. Lyon, France: IARC Press, 595 pp, 2001.
\12\ Grogan HA, Sinclair WK, and Voilleque PG. ``Risks of fatal
cancer from inhalation of 239,240plutonium by humans: a combined
four-method approach with uncertainty evaluation'' Health Physics
80:447-461, 2001.
---------------------------------------------------------------------------
Limitations of current research and development have prevented
NIOSH from considering and implementing all possible improvements to
IREP at this time. In the future, NIOSH may make additional changes in
IREP to address differences in radiation-related cancer risk between
Japanese atomic bomb survivors and employees involved in nuclear
weapons production. Some research has shown substantial differences in
risk for certain cancers, such as brain cancer and multiple myeloma
13. The radiation-related risk of these cancers is
significantly elevated among employees involved in nuclear weapons
production, whereas it is not among the Japanese study population. The
IREP risk models for these cancers were produced using data from the
Japanese study population.
---------------------------------------------------------------------------
\13\ Alexander V and DiMarco JH. ``Reappraisal of brain tumor
risk among U.S. nuclear workers: a 10-year review.'' Occupational
Medicine: State of the Art Reviews 16(2):289-315, 2001.
Cardis E, Gilbert ES, Carpenter L, et al. ``Effects of low doses
and low dose rates of external ionizing radiation: cancer mortality
among nuclear industry workers in three countries.'' Radiat. Res.
142:117-132, 1995.
---------------------------------------------------------------------------
Similarly, it may be possible to improve the fit of IREP risk
models to employees covered by EEOICPA with respect to differences
between the frequency of certain cancers in the general population in
the United States versus Japan. The IREP risk models include a
simplistically derived factor (risk transfer) that accounts for these
differences, based on expert judgment. For some cancers, such as breast
and stomach cancer, sufficient research may exist to improve this
factor. In addition, where current IREP risk models could be replaced
with risk models based on studies of U.S. DOE workers, or other U.S.
populations, this factor could be omitted entirely. The potential
future use of risk models based on studies of U.S. DOE workers may also
eliminate limitations arising because data are sparse for certain
cancers among the Japanese atomic bomb survivors, such as most specific
types of leukemia. Using data on the Japanese cohort, the effect on
risk of age at time of exposure to radiation, an important modifier of
leukemia risk, cannot be estimated for specific types of leukemia,
except chronic myeloid leukemia. It can only be estimated for other
leukemia types by using a general leukemia model that combines data
from cases of different types of leukemia.
Finally, NIOSH may make modifications in cancer risk models in
IREP, as appropriate and if feasible, to account for the changing
frequency among the general population (baseline rates) of certain
types of cancer in the United States. Certain types of cancer (e.g.,
lung cancer among women, breast cancer) have become more frequent in
recent decades. Similarly, NIOSH may make modifications in cancer risk
models to reflect the differing frequency of certain types of cancer
among different racial and ethnic groups in the United States (e.g.,
multiple myeloma). The effect of these modifications, at such time as
they may become available, would be to improve the accuracy of
probability of causation estimates.
H. Procedures for Review and Public Comment on NIOSH-IREP
As described under Section G above, some current and potential
future changes to the cancer risk models in IREP are particularly
appropriate for addressing the radiation exposures and statutory
requirements of claimants under EEOICPA. As a result, the version of
IREP to include NIOSH modifications will be unique and distinguished as
``NIOSH-IREP.'' This version, which DOL will use to estimate
probability of causation under EEOICPA, will be reviewed by the
Advisory Board on Radiation and Worker Health. NIOSH-IREP is available
for public review on the NIOSH homepage at: www.cdc.gov/niosh/ocas/ocasirep/html. It includes documentation of underlying risk models and
calculations. The public can obtain complete information about NIOSH-
IREP by contacting NIOSH at its toll-free telephone information
service: 1-800-35-NIOSH (1-800-356-4674).
The public may comment on NIOSH-IREP at any time. Comments can be
submitted by e-mail to [email protected], or by mailing written comments to:
NIOSH-IREP Comments, National Institute for Occupational Safety and
Health, 4676 Columbia Parkway, MS-R45, Cincinnati, Ohio 45226. All
comments will be considered. In addition, NIOSH will forward all
substantive comments to the Advisory Board on Radiation and Worker
Health, which will have an ongoing role to review and advise NIOSH on
possible changes to NIOSH-IREP, as described in this rule.
I. Operating Guide for NIOSH-IREP
DOL will use procedures specified in the NIOSH-IREP Operating Guide
to calculate probability of causation estimates under EEOICPA. The
guide provides current, step-by-step instructions for the operation of
NIOSH-IREP. The procedures include entering personal, diagnostic, and
exposure data; setting/confirming appropriate values for variables used
in calculations; conducting the calculation; and, obtaining,
evaluating, and reporting results.
[[Page 22300]]
An initial version of the NIOSH-IREP Operating Guide is available
to the public online on the NIOSH homepage at: www.cdc.gov/niosh/ocas/ocasirep/html. The public can obtain printed copies by contacting NIOSH
at its toll-free telephone information service: 1-800-35-NIOSH (1-800-
356-4674).
II. Summary of Public Comments
On October 5, 2001, HHS proposed guidelines for determining
probability of causation under EEOICPA (42 CFR 81; see 66 FR 50967).
HHS initially solicited public comments from October 5 to December 4,
2001. The public comment period was reopened subsequently from January
17, 2002 to January 23, 2002 for public comments, and from January 17,
2002 to February 6, 2002, for comments from the Advisory Board on
Radiation and Worker Health (67 FR 2397).
HHS received comments from 12 organizations and 24 individuals.
Organizations commenting included several labor unions representing DOE
workers, a community based organization, an administrative office of
the University of California, several DOE contractors, and several
federal agencies. A summary of these comments and HHS responses is
provided below. These are organized by general topical area.
A. Appropriateness of Adapting Compensation Policy Used for Atomic
Veterans
One commenter requested explanation of the appropriateness of
adapting existing compensation policy for atomic veterans to a
compensation program for nuclear weapons workers. The comment appears
to question whether this existing policy for atomic veterans is an
appropriate starting point from which to develop compensation policy
under EEOICPA. In the notice of proposed rulemaking, HHS had solicited
public comment on whether it had appropriately adapted compensation
policy for atomic veterans to meet the needs of this workforce, which
has a substantially different occupational and radiation exposure
experience.
Congress determined the veteran's compensation policy as a starting
point for HHS. It did so by requiring the determination of probability
of causation based on radiation doses and the use of the NIH
Radioepidemiological Tables, and by requiring that the cancer covered
in a claim be determined to be ``at least as likely as not'' caused by
radiation doses incurred in the performance of duty, based on the upper
99 percent credibility limit. These are defining features of
compensation policy for atomic veterans.
The public should also recognize that the Radioepidemiological
Tables required years to initially develop and then additional years to
update (the update is not completed). Without this critical, highly
sophisticated element developed for the veterans' program, it would not
have been possible to establish and implement a policy for nuclear
weapons workers in a timely fashion.
HHS adapted these policies for nuclear weapons workers through two
prominent measures, discussed in the notice of proposed rulemaking and
below. HHS included provisions to allow NIOSH to adapt the cancer risk
models in the latest version of the NIH Radioepidemiological Tables to
reflect the unique radiation exposure experience of nuclear weapons
workers. And HHS established transparent, objective procedures for DOL
to handle a variety of circumstances in which various information
relevant to determining probability of causation will be unknown. The
majority of comments received on this rule suggest most commenters view
as appropriate the measures HHS has taken to adapt existing
compensation policy to this new program.
B. Compensability
Various comments relating to the use of these guidelines were
received. Specifically, HHS received comments on: awarding compensation
based upon a proportional level of probability of causation; the use of
the upper 99 percent confidence limit to estimate probability of
causation; awarding compensation for employees who incurred radiation
doses within regulated radiation safety limits; automatically
qualifying employees who incurred doses in excess of the maximum
allowable radiation dose under Atomic Energy Commission regulations;
waiving dose reconstruction and probability of causation for employees
with rare cancers; and automatically compensating employees for whom
DOE is unwilling or unable to provide employment records.
The development and use of these guidelines for determining
compensability and the benefit structure are statutorily mandated and
therefore these comments were not adopted.
One commenter suggested prohibiting the use of probability of
causation findings as proof of fault in litigation. This suggestion was
not adopted because prohibiting the use of probability of causation
findings for litigation purposes is not authorized by the statute.
However, because these findings will be based on NIOSH dose
reconstructions, which will not always produce complete or best
estimates of the actual doses received by an individual,14
HHS does not believe these findings should be used for any purpose
other than the adjudication of claims under EEOICPA.
---------------------------------------------------------------------------
\14\ For explanation of these possible limitations of NIOSH dose
reconstructions, see the discussion under ``II. Summary of Public
Comments; A. Purpose of the Rule'' in the preamble of 42 CFR Part 82
(the HHS dose reconstruction rule).
---------------------------------------------------------------------------
C. Need for Peer Review
Several commenters recommended that HHS obtain peer review of the
cancer risk models that comprise NIOSH-IREP, and of changes to NIOSH-
IREP, as it is updated based on progress in the underlying sciences.
Several commenters recognized that the Advisory Board on Radiation and
Worker Health is intended by HHS as one means of obtaining such peer
review, but the commenters raised concerns about whether the Board
would have sufficient expertise for this purpose.
HHS recognizes the importance of peer review. Consequently, as
indicated above, the National Cancer Institute obtained peer review of
IREP by the National Research Council. NCI and NIOSH have made
modifications in IREP consistent with this peer review. NIOSH has also
obtained peer-review by independent subject matter experts of changes
developed by NIOSH to adapt IREP to the experience of nuclear weapons
workers. These peer-reviews are posted on the NIOSH website and are
also available to the public by request.
In addition, the Advisory Board on Radiation and Worker Health will
be reviewing the cancer risk models in NIOSH-IREP, as indicated above
and in the notice of proposed rulemaking. Contrary to the public
comments noted above, HHS finds the Board has appropriate expertise for
such a review, including eminent physicians and scientists from the
field of health physics. Moreover, the Board maintains the option to
commission additional independent scientists to participate in the
Board's review. HHS also has the option to obtain additional peer
reviews by the National Academy of Sciences, as recommended by some
commenters.
In response to comments recommending peer review and to the
recommendations of the Advisory Board on Radiation and Worker Health
discussed below, HHS has added a new requirement to this rule to affirm
the commitment of HHS to involve the
[[Page 22301]]
Board in peer-review of future decisions to change NIOSH-IREP and to
ensure this process is open to public participation. These provisions,
which were previously contained in the preamble of the notice of
proposed rulemaking, are now incorporated into the rule itself under
Sec. 81.12.
One commenter recommended HHS extend the comment period of the rule
to provide the public with additional time to review NIOSH-IREP.
As indicated in the notice of proposed rulemaking and above, the
public can comment on NIOSH-IREP at any time. The rule comment period
applies only to provisions of the rule itself.
D. Updating NIOSH-IREP to Remain Current With Science
Commenters supported the intent of HHS to update NIOSH-IREP as
scientific progress enables HHS to improve the cancer risk models. Two
commenters recommended that DOL apply updates to NIOSH-IREP
retrospectively to claims that were denied on the basis of a
probability of causation finding that might change as a result of the
update.
Under 42 CFR 81.12 NIOSH will notify the public and DOL when
changes to NIOSH-IREP are completed and explain the effect of changes
on probability of causation estimates. This will enable DOL and
claimants with denied claims to identify denied claims potentially
affected by the changes and evaluate the effect of this new
information.
E. Chemical or Non-Occupational Radiation Exposures as Risk Factors
Some nuclear weapons workers were exposed to potential and known
chemical carcinogens as well as radiation in the performance of duty.
Several commenters urged that cancer risk models in NIOSH-IREP take
into account the effects that these combined or ``mixed'' exposures
might have on risk associated with radiation exposure.
There is no adjustment in NIOSH-IREP for chemical exposures. It is
not clear that the state of science presently could support risk
adjustments that account for possibly differing roles of chemical
exposures. A second, probably overriding, practical concern is whether
this compensation program for nuclear weapons workers, which already
requires the collection and consideration of large amounts of
information, could produce fair, timely decisions with the addition of
a substantial new informational burden. New information would be
required for each claim regarding the type, level, duration, and timing
of relevant chemical exposures, as well as the use of administrative
measures and protective equipment to protect exposed workers.
Despite these limitations, NIOSH will consider taking into account
the effect of mixed exposures at such time as this may become
scientifically supportable and feasible. HHS has added section
81.10(b)(4) to specifically include this possibility.
Several other commenters made similar but distinct recommendations
to modify the cancer risk models in NIOSH-IREP to account for cancer
risks that might be independent of radiation risks, arising from
occupational and community exposures to chemicals or non-occupational
exposures to radiation. Some commonplace examples of such exposures
might include exposures to solvents or preservatives used at work or
home, radon in the home, second-hand tobacco smoke, or sun exposure.
The recommendation relates to the fact that groups have different
``background'' risks of cancers depending on their exposure to these
various carcinogens. Groups with higher than normal background risks
might be shown in studies of radiation risks to have lower increases in
cancer risk attributable to radiation. Likewise, groups with lower than
normal background risks might be shown to have higher increases in risk
attributable to radiation, depending on the form of interaction between
radiation exposures and these other cancer risk factors.
It is not scientifically supportable or feasible to adjust NIOSH-
IREP risk models for the multitude of occupational and community
exposures. The carcinogenic risks associated with most chemical
exposures, and the appropriate form of their interaction with
radiation, have not been adequately quantified. Moreover, DOL generally
would not have access to exposure data on the individual's exposure to
chemicals or radiation in the community. As discussed above, access to
data on occupational exposures to chemicals is also infeasible at this
time.
F. Covered Exposures
A few commenters recommended changes in the set of exposures
included by this rule to contribute to the probability of causation
calculation.
Several commenters recommended against HHS including medical
screening x rays administered to nuclear weapons employees as a
condition of employment. Similar comments were received on the interim
final HHS dose reconstruction rule (42 CFR 82) as well. Commenters
argue that the benefit of these exposures justifies their attendant
risks, and therefore they should not contribute to the acceptance of a
claim for compensation.
HHS will not exclude radiation exposures resulting from these
occupationally required medical screening x rays. The important factor
in this decision is that the exposures were incurred ``in the
performance of duty,'' as specified by EEOICPA. The employees were
required to receive these x ray screenings and hence were exposed to
radiation in performing this duty.
Several commenters recommended HHS include cancer risks associated
with chemical exposures and in effect calculate a probability of
causation related to all occupational exposures, rather than radiation
exposures alone.
HHS cannot include the cancer risks associated with chemical
exposures in the calculation of probability of causation. EEOICPA
explicitly limits these guidelines and DOL to making determinations as
to whether the cancer subject to a claim was caused by radiation doses
incurred in the performance of duty (see Sec. 7384(n)(c) of EEOICPA).
G. Covered Illnesses
HHS received several comments addressing the exclusion or inclusion
of illnesses covered by these guidelines.
Several commenters noted that EEOICPA only covers cancers but
should cover other or all illnesses. A second commenter recommended
that probability of causation should be determined for inherited
genetic effects (among offspring of covered workers).
The probability of causation guidelines cover only cancers because
this is a statutory requirement of EEOICPA (see discussion of statutory
requirements above). Moreover, science has not progressed sufficiently
to permit probability of causation determinations for many radiogenic
illnesses other than cancers; specifically not for inherited genetic
effects.
Readers should note, however, that part B of EEOICPA, which
provides lump sum payments of $150,000 as well as medical benefits,
provides coverage for chronic beryllium disease and silicosis (when
incurred by workers exposed in connection with mining of tunnels for
atomic weapons tests or experiments in Nevada or Alaska), two well
documented occupational illnesses. Part B also provides for medical
monitoring of covered workers with beryllium sensitivity. In addition,
part D of EEOICPA provides assistance through a worker advocacy program
administered by DOE to assist nuclear
[[Page 22302]]
weapons workers with illnesses that might have resulted from toxic
occupational exposures who are seeking state workers' compensation
benefits. Panels of expert physicians appointed by HHS will review the
medical records in connection with each of these cases and make a
determination as to whether the illness was likely to have been caused
by toxic occupational exposures.
Another commenter recommended that HHS not permit probability of
causation to be determined for cancers in situ--that is, cancers that
have yet to spread to neighboring tissues. In other words, the comment
recommends assigning a probability of causation of zero to individuals
with this early stage of cancer.
HHS is retaining the procedures it proposed for estimating
probability of causation for carcinomas in situ, treating them within
NIOSH-IREP identically to invasive cancers. Although more research is
needed, some studies have shown the risk factors for a carcinoma in
situ are similar to cancer at a later stage. In addition, for any given
individual, it is not possible to determine which carcinomas in situ
will progress to become invasive cancers.
H. Radiation Dose Threshold for Calculating Probability of Causation
Several commenters recommended HHS establish a radiation dose
threshold below which DOL would deny the claim without calculating
probability of causation. One commenter proposed NIOSH-IREP be modified
to take into account alternative theories of radiation effects at low
cumulative doses. The commenters argue that it is unknown whether
cancers can be caused at radiation doses below 10 to 20 rem. In
addition, several commenters note that claims for rare cancers, for
which there is likely to be a high level of uncertainty about the dose-
risk relationship, would have unfair advantage over claims for more
common cancers, due to the use of the 99 percent credibility limit.
The National Research Council, which reviewed IREP, noted concern
about the effect of uncertainty with respect to rare cancers. NCI has
responded to this concern by grouping rare cancers in more general
cancer categories, for which there is a more robust research basis for
quantifying risk.
HHS does not find that any further measures are necessary,
particularly the application of a threshold. The issue of whether or
not there is a threshold for causation of cancer by radiation is
controversial. Moreover, the issue is avoided by the practical approach
taken in this rule. Doses resulting in a probability of causation
finding of 50 percent or greater are determined based on current and
cumulative epidemiologic findings. The NCI solution of grouping rare
cancers addresses the concern about high levels of uncertainty for rare
cancers.
I. Non-Radiogenic Cancers
One commenter recommended against the proposed rule's consideration
of chronic lymphocytic leukemia (CLL) as non-radiogenic (Sec. 81.30).
This provision requires DOL to assign a probability of causation of
zero for a claim for CLL. The commenter asserts that it cannot be
proven that this form of leukemia is non-radiogenic.
As discussed in the notice of proposed rulemaking and below, CLL is
widely considered non-radiogenic by the radiation health research
community and is not covered by other radiation compensation programs.
Moreover, there is no risk model appropriate to CLL, nor data to
support the development of such a risk model. Consequently, it is not
possible to calculate probability of causation for CLL and it is both
appropriate and necessary to consider CLL as non-radiogenic for the
purposes of this rule.
J. Documentation of NIOSH-IREP
Several commenters recommended NIOSH fully document the risk models
and calculations of NIOSH-IREP so that the basis for its calculations
are fully transparent. One commenter added that in this documentation,
NIOSH should explain how different sources of uncertainty are taken
into account.
NIOSH agrees with the comment and, as indicated in the notice of
proposed rulemaking, is committed to maintaining and providing full
documentation on NIOSH-IREP. To a substantial extent, this
documentation is directly available to the public while using or
examining NIOSH-IREP. The software, which is accessible for public use
from the NIOSH homepage on the internet, has a feature that allows the
user to call-up the formulae and information underlying each
calculation. The user can also call-up graphic illustrations (pie
charts) that quantitatively depict the role of different sources of
uncertainty in contributing to the overall uncertainty calculated for
use in a probability of causation estimate.15 As noted
above, the documentation is also available in print form by contacting
NIOSH.
---------------------------------------------------------------------------
\15\ The uncertainty distributions for the various sources of
uncertainty involved in a probability of causation estimate are
combined in NIOSH-IREP using a Monte Carlo simulation program that
draws values randomly, repeatedly from each distribution to derive a
single, representative uncertainty distribution.
---------------------------------------------------------------------------
K. Current Technical Elements of NIOSH-IREP
HHS received a variety of comments on specific aspects of the
cancer risk models in NIOSH-IREP. While these risk models are not
themselves subject to this rulemaking, HHS is committed to receiving
and responding to public comments on NIOSH-IREP, and making
improvements as appropriate. As indicated in Sec. 81.12 of this rule,
recommendations for modifications to NIOSH-IREP will be addressed
routinely through a public process involving the Advisory Board on
Radiation and Worker Health. Hence, HHS addresses current comments
submitted during the rulemaking comment period below, but notes that
some of these issues may receive further consideration subsequent to
this rulemaking, once HHS has obtained advice on these issues by the
Advisory Board. The Advisory Board has received these public comments
for review.
One commenter generically recommended against making use in NIOSH-
IREP of cancer risk models developed for determining probability of
causation for atomic veterans. As discussed above and in the notice of
proposed rulemaking, most of the risk models in IREP were developed
based on the exposure and disease experience of Japanese survivors of
the atomic bomb detonations in World War II. The commenter finds the
differences between the exposure conditions of these survivors and
those of nuclear weapons employees too great to support probability of
causation determinations for the latter.
HHS recognizes the substantial differences between the radiation
exposure experiences of these two populations and discussed these
differences above and in the notice of proposed rulemaking. To address
these differences, NIOSH has adapted the available risk models to the
extent feasible and supportable using current science. The difference
in exposure characteristics is also part of the rationale for the
provisions of this rule supporting updates of NIOSH-IREP, as scientific
progress allows additional improvements. One of the specified goals of
such updates is to use, as this becomes feasible, risk findings derived
from occupational health studies of nuclear weapons workers.
Nonetheless, NIOSH maintains that the current scientific basis
applied in
[[Page 22303]]
NIOSH-IREP is the best available at this time and that its use is both
reasonable and fair. As discussed throughout this rule, NIOSH has taken
into account, whenever feasible, recognized limitations in the current
state of relevant sciences.
Several commenters recommended changes in the way the lung cancer
risk model adjusts risk according to the individual's smoking history.
The risk model produces a higher probability of causation that lung
cancer was caused by radiation for a non-smoker than a smoker, at a
given level and pattern of radiation exposure.
One commenter indicated that the probability of causation estimate
for a heavy smoker should be much lower than currently estimated by the
risk model. The other commenters recommended the opposite, that NIOSH
should eliminate adjustment for smoking history. They assert research
indicates that smoking may have a multiplicative effect on lung cancer
risk, when combined with radiation exposure. If this research were
proven correct, then smoking history would not affect the contribution
of radiation to cancer risk, and could indeed be omitted from
consideration.
The adjustment for smoking history in NIOSH-IREP has been adopted
from the approach developed by NCI, and fully takes into account the
cumulative body of research evaluating the interaction between smoking
and radiation risks, as well as leading scientific views on this
research. The NCI review of relevant literature, and a scientific
consensus panel opinion (UNSCEAR 200016), conclude that the
best-supported risk models to evaluate the form of interaction between
smoking and radiation are based on meta-analyses of radon-exposed
workers. Combined analyses of these studies suggest that the most
appropriate form of interaction is sub-multiplicative (i.e., the excess
relative risk from radiation exposure among smokers is less than the
excess relative risk among non-smokers), but greater than additive
(Lubin and Steindorf 1995). NCI used this scientific basis to develop
an uncertainty distribution for the form of interaction between smoking
and radiation in the lung cancer risk models that is centered on a sub-
multiplicative model (i.e., a model which assumes the excess relative
risk of cancer per unit of radiation dose is lower for individuals who
smoke more), but includes the possibility of either a multiplicative
model (i.e., that excess relative risk per unit of radiation dose is
the same for various levels of smoking, including non-smokers) or a
super-multiplicative model (i.e., that excess relative risk per unit
dose is higher for individuals who smoke more). As with all
assumptions, this uncertainty distribution is subject to modification
in future revisions of NIOSH-IREP, pending the availability of new
scientific information.
---------------------------------------------------------------------------
\16\ United National Scientific Committee on the Effects of
Atomic Radiation. 2000. Sources and Effects of Ionizing Radiation:
UNSCEAR 2000 Report to the General Assembly, with Scientific
Annexes, Volume II: Effects; p. 201-203.
Lubin JH and Steindorf K. 1995. Cigarette use and the estimation
of lung cancer attributable to radon in the United States. Radiat.
Res. 141:79-85.
---------------------------------------------------------------------------
Several commenters recommended against use of a factor that reduces
cancer risk for workers who were exposed to radiation at older ages. In
support of this recommendation, they contend atomic bomb survivor and
occupational studies do not find an inverse relationship for adults
between age at time of radiation exposure and cancer risk.
NIOSH is using in NIOSH-IREP the NCI approach to adjusting
radiation risk estimates for different exposure ages. This approach is
based on new epidemiological analyses of atomic bomb survivors who were
of working age when exposed during the blast, and uses an approach
recommended by an international expert committee (Pierce et al. 1993,
UNSCEAR 2000 17). It addresses all solid cancers except skin
and thyroid. Thus, for most cancers NIOSH-IREP relies on direct
evidence from the A-bomb survivors exposed as adults rather than as
children. NCI did not incorporate any age at exposure effect for the
following cancers: acute myeloid leukemia, chronic myeloid leukemia,
lung cancer (non-radon exposures), and female genital cancers other
than ovary. The NCI models do incorporate a trend of decreasing risk
per unit dose with increasing age at exposure for the following cancer
sites: acute lymphocytic leukemia, all leukemia other than chronic
lymphocytic, basal cell carcinoma, and cancers of thyroid. For radon
exposures and lung cancer, there is no direct adjustment for exposure
age: risks are dependent on time since last exposure and on age at
diagnosis. The effect of this adjustment is that, at a constant ``time
since last exposure'', the risk decreases for increasing age at last
exposure; however, for constant ``age at diagnosis'', the risk
increases for increasing age at last exposure. For all other cancers,
the NCI models incorporate a trend of decreasing risk per unit dose for
exposure ages between 15 and 30, and assume constancy (no effect of
age) thereafter.
---------------------------------------------------------------------------
\17\ Pierce DA, Preston DL. 1993. Joint analysis of site-
specific cancer risks for the A-bomb survivors. Radiat. Res.
137:134-142.
United National Scientific Committee on the Effects of Atomic
Radiation. 2000. Sources and Effects of Ionizing Radiation: UNSCEAR
2000 Report to the General Assembly, with Scientific Annexes, Volume
II: Effects; p. 208.
---------------------------------------------------------------------------
There is substantial evidence from several key studies in addition
to those of the A-bomb cohort that suggests radiation risk for many
cancers decreases with increasing age at exposure. These include
studies of breast cancer among x-ray tuberculosis patients (Boice et
al. 1991 18), of thyroid cancer among medically- and
occupationally-exposed populations (summarized in UNSCEAR 2000a3), and
of skin cancer (UNSCEAR 2000b3). While some studies of DOE workers
suggest no effect or find increased relative risk estimates for certain
cancers from exposure to radiation at older ages, this information is
insufficient to support the selection of appropriate cancers and an
appropriate method for quantitatively incorporating this information
into risk adjustments in NIOSH-IREP. As indicated in the rule, HHS will
re-evaluate this issue in future revisions of NIOSH-IREP, as warranted
by advances in scientific information.
---------------------------------------------------------------------------
\18\ Lubin JH, Boice JD Jr, Edling C, et al. 1995. Lung cancer
risk in radon-exposed miners and estimation of risk from indoor
exposure. J. Natl. Canc. Inst. 87:817-827.
Boice JD Jr, Engholm G, Kleinerman RA, et al. 1991. Frequent
chest x-ray fluoroscopy and breast cancer incidence among
tuberculosis patients in Massachusetts. Radiat. Res. 125:214-222.
United National Scientific Committee on the Effects of Atomic
Radiation. 2000a. Sources and Effects of Ionizing Radiation: UNSCEAR
2000 Report to the General Assembly, with Scientific Annexes, Volume
II: Effects; p. 338-343.
United National Scientific Committee on the Effects of Atomic
Radiation. 2000b. Sources and Effects of Ionizing Radiation: UNSCEAR
2000 Report to the General Assembly, with Scientific Annexes, Volume
II: Effects; p. 402.
Richardson DB, Wing S, Hoffmann W. 2001. Cancer risk from low-
level ionizing radiation: the role of age at exposure. Occupat.
Med.: State of the Art Reviews 16:191-218.
---------------------------------------------------------------------------
Several commenters recommended adding a risk adjustment factor to
NIOSH-IREP to account for a possible ``healthy survivor effect''
presently unaccounted for in the research on Japanese atomic bomb
survivors. The theory underlying this comment is that atomic bomb
survivors may be healthier than the general public and less likely to
incur cancer. Therefore, according to this theory, it would be mistaken
to equate the level of increased cancer risk from radiation among this
robustly healthy population to the level of increased cancer risk among
the U.S. population, with its normal distribution of health. If this
were proven correct, the risk models in NIOSH-IREP should
[[Page 22304]]
be adjusted to increase the level of cancer risk caused by a unit of
radiation dose, since the U.S. population would presumably be more
susceptible than the Japanese survivor population to the cancer-causing
effects of radiation.
The possible existence of a healthy survivor effect has been
theorized by some researchers (Stewart and Kneale 199019),
and has been determined by others to be of small magnitude or non-
existent (Little and Charles 1990, NCRP 1997). The NCI determined that
insufficient information on the possible effect of this bias is
available for use the IREP program. NIOSH, in consultation with the
Advisory Board on Radiation and Worker Health, will consider whether to
add an adjustment factor to future versions of NIOSH-IREP to account
for a possible healthy survivor effect, if supported by new scientific
information. HHS notes such a finding would be equally relevant for
claimants under EEOICPA and under the Atomic Veterans Compensation
Program, and thus should be decided by scientific consensus between
these two programs whose relevant policies are both determined by HHS.
---------------------------------------------------------------------------
\19\ Stewart AM, and Kneale GW. 1990. A-bomb radiation and
evidence of late effects other than cancer. Health Phys. 58:729-735.
Little MP, and Charles MW. 1990. Bomb survivor selection and
consequences for estimates of population cancer risks. Health Phys.
59:765-775.
National Council on Radiation Protection and Measurements
(NCRP). 1997. Uncertainties in fatal cancer risk estimates used in
radiation protection. NCRP report 126. 112 pp.
---------------------------------------------------------------------------
Several commenters recommended changing the factor in NIOSH-IREP
that reduces cancer risk for workers who were exposed to low linear
energy transfer (LET) 20 radiation at low dose rates
(workers who received many small doses of radiation, versus fewer large
doses). They cite reports by the Nuclear Regulatory Commission and the
International Agency for Research on Cancer as finding no relationship
between the rate at which low LET radiation doses are incurred and the
risk of cancer.
---------------------------------------------------------------------------
\20\ See Sec. 81.4 in rule for a definition of LET.
---------------------------------------------------------------------------
HHS agrees that this is an area of substantial uncertainty. Many
studies suggest that risks are reduced for particular cancers when
doses are fractionated or received at low dose-rate, while other
studies suggest no effect of dose-rate or dose fractionation on
radiation risk.
NIOSH-IREP accounts for this uncertainty. For chronic exposures,
NIOSH-IREP adopts the approach used in the final revision of the NCI-
IREP program, which more heavily weights a probability that there is no
attenuation of risk at low dose rates of exposure. This uncertainty
distribution also includes a small probability that dose-rate reduction
or dose fractionation enhances, rather than reduces, radiation risk.
One commenter recommends that NIOSH-IREP account for a possible
inverse relationship between exposure to low doses of high LET
radiation and cancer risk. The commenter cites recent research
suggesting that individuals who incurred high LET radiation doses at
lower rates had higher risk of cancer, compared with individuals who
incurred the same cumulative doses at higher rates.
As indicated in the notice of proposed rulemaking and above, NIOSH
has incorporated the possibility of this inverse relationship into
NIOSH-IREP for both neutron and low-LET exposures. Based on reviews of
subject matter experts, the revised version of NIOSH-IREP includes a
small probability of an inverse dose-rate effect for alpha radiation
exposures as well.
One commenter noted that a linear-quadratic model of the dose-risk
relationship is not equivalent to use of a dose-rate correction factor
to reduce the per-unit contribution of low doses to cumulative risk of
cancer. The commenter recommended either using a dose-rate correction
factor to keep these model elements separate, or alternatively to
explain why it is appropriate to use the linear-quadratic model to
mimic a reduced cancer risk effect at low dose rates.
This comment is contradicted by several research groups, including
the NCI-IREP working group, the NIH Ad Hoc Working Group which
initially developed the Radioepidemiological Tables (NIH 1985
21), and the Committee on Biological Effects of Ionizing
Radiation (BEIR)V. The BEIR V committee explicitly states that ``[Dose
rate] reductions should be applied only to the non-leukemia risks, as
the leukemia risks already contain an implicit DREF [dose rate
effectiveness factor] owing to the use of the linear-quadratic model''
22. The theoretical basis for this equivalence is the
observation that the use of a linear-quadratic dose assumption applies
a reduction in risk that is equivalent to using a dose-and-dose-rate
reduction factor of about two, which has been commonly recommended by
advisory groups for modeling leukemia risk.
---------------------------------------------------------------------------
\21\ National Institutes of Health (NIH). 1985. Report of the
National Institutes of Health Ad Hoc Working Group to Develop
Radioepidemiological Tables. US DHHS. NIH Publication No. 85-2748,
p. 88.
\22\ National Research Council. 1990. Health Effects of Exposure
to Low Levels of Ionizing Radiation: BEIR V. National Academy Press,
Washington, DC. 421 pp., p.174.
---------------------------------------------------------------------------
One commenter recommended NIOSH change the dose and dose rate
effectiveness factor (DDREF) for leukemia (for low LET radiation
exposure) to three. This would reduce by two-thirds the probability of
causation estimates for workers with leukemia who accrued their
cumulative radiation doses slowly. The commenter cites two studies to
support this recommendation.
NIOSH-IREP uses the models developed by the NCI Working Group for
leukemia risk from low-LET exposure. As discussed previously, rather
than incorporating a DDREF of greater than one for leukemia risk
models, the dose-response function for leukemia is of the linear-
quadratic form. This corresponds approximately to a DDREF of two for
leukemia risk at low compared to high doses and dose rates. This
approach has been recommended by several expert committees, referenced
above.6, 7 While findings from individual
epidemiological studies may vary from this approach, these individual
study findings are subject to the limitations of the studies. For this
reason, risk modeling requires consideration of the totality of
scientific evidence regarding the effects of dose protraction.
Consistent with the extensive expert analyses cited above, NIOSH-IREP
uses a linear-quadratic model with uncertainty in the model parameters,
which best captures the uncertainties associated with the effects at
low doses and dose rates.
One commenter recommends NIOSH obtain peer review for the radiation
weighting factors used in NIOSH-IREP. These weighting factors take into
account the differing biological effect potency of different types of
radiation in inducing cancer. The commenter states that a factor of 40
used for alpha radiation in NIOSH-IREP, that this is ``too
conservative'' (i.e., results in probability of causation estimates
that would be higher than scientifically justified), and notes that the
International Commission on Radiological Protection (ICRP) intends to
lower its recommended weight for alpha radiation from 20 to 10.
The commenter misunderstands how information on the biological
effectiveness of radiation types is used in NIOSH-IREP. The ICRP and
other leading expert groups recommend weighting factors in the form of
point estimates to summarize the differing biological effectiveness of
various types of radiation for use by radiation protection programs.
These programs
[[Page 22305]]
require a point estimate to calculate appropriate safety criteria that
can be applied to protect populations. On the other hand, the task
involving NIOSH-IREP is to calculate probability of causation for
individual claims, taking into account sources of scientific
uncertainty. There is substantial uncertainty of science in describing
the biological effectiveness of various types of radiation, and in part
due to this uncertainty, there are differences in the review findings
of ICRP, the International Commission on Radiation Units and
Measurements, and the National Council on Radiation Protection and
Measurements. In addition, some radiation exposures are incompletely
addressed by the reviews by these expert groups.
To evaluate scientific uncertainty, NIOSH analyzed the reviews of
biological effectiveness of radiation by each of the expert committees
cited above and, where these reviews were incomplete, other expert
reviews and primary research as well. Based on this analysis, NIOSH
established the central tendency of ``relative biological
effectiveness'' for each type of radiation and assigned a probability
distribution to describe the scientific uncertainty about the central
tendency estimate. To calculate probability of causation, NIOSH-IREP
will apply these resulting uncertainty distributions derived by NIOSH,
instead of point estimate weighting factors, to account for the
differing biological effectiveness of various radiation types.
The NIOSH analysis of relative biological effectiveness described
here has been summarized in a scientific paper, peer-reviewed by
subject matter experts, and revised accordingly. It is available to the
public, along with the peer-review comments, from the NIOSH homepage on
the internet or by direct request to NIOSH (addresses provided above)
23.
---------------------------------------------------------------------------
\23\ The paper was originally titled: ``Proposed Radiation
Weighting Factors for Use in Calculating Probability of Causation
for Cancers'' and is now published with revisions and more extensive
explanation under the title: ``Relative Biological Effectiveness
Factors (RBE) for Use in Calculating Probability of Causation of
Radiogenic Cancers.''
---------------------------------------------------------------------------
One commenter questions how the lung cancer model for radon in
NIOSH-IREP compares with the recommendations of the Committee on Health
Risks of Exposure to Radon (BEIR VI) 24.
---------------------------------------------------------------------------
\24\ National Research Council. 1999. Health Effects of Exposure
to Radon: BEIR VI. National Academy Press, Washington, DC. 500 pp.
---------------------------------------------------------------------------
As discussed in the notice of proposed rulemaking and above, the
lung cancer model for radon in NIOSH-IREP was developed based on an
analysis of risk by the Radiation Exposure Compensation Act (RECA)
Committee 25, as recommended by the National Research
Council review of the NCI IREP software. The RECA committee recommended
scientific methods for adapting the radon and lung cancer risk models
derived from uranium miner research to compensation decisions. These
research findings were an important component of the BEIR VI analyses
as well.
---------------------------------------------------------------------------
\25\ Final Report of the Radiation Exposure Compensation Act
Committee, submitted to the Human Radiation Interagency Working
Group, July 1996 (Appendix A), 30 pp (plus Figures).
---------------------------------------------------------------------------
L. HHS Dose Reconstruction Program (42 CFR 82)
HHS received several comments addressed to this rule that relate to
HHS dose reconstructions under EEOICPA. In some cases, the comments
were directed to this rule because dose reconstruction results serve as
inputs to calculate probability of causation. The HHS rule establishing
methods for dose reconstruction, 42 CFR Part 82, is being published
simultaneously in this issue of the Federal Register.
Several commenters recommended that these guidelines prescribe the
selection of uncertainty distributions associated with radiation dose
information supplied by the NIOSH dose reconstruction.
As discussed in the dose reconstruction rule, uncertainty
distributions associated with the dose information will indeed be
defined by NIOSH in its individual dose reconstruction final reports
provided to DOL, the claimant, and DOE. This information, also included
in the electronic dose files provided to DOL by NIOSH, will be imported
into NIOSH-IREP by DOL when it calculates probability of causation.
These uncertainty distributions associated with dose information
cannot be generically prescribed by these guidelines. This information
will vary substantially depending on radiation exposure circumstances
and informational sources associated with each claim. Therefore, NIOSH
will be defining the use of appropriate uncertainty distributions on a
claim-by-claim basis, based on technical procedures established by
NIOSH to implement the HHS dose reconstruction rule.
One commenter recommended NIOSH use a default assumption that
characterizes radiation doses as chronic rather than acute. The
commenter indicated that the radiation doses incurred by many workers
are more accurately characterized as chronic using traditional
definitions.
NIOSH will characterize radiation doses as chronic when it has
information to substantiate this designation. However, in most cases
NIOSH is unlikely to have sufficient information to make this
distinction. For these cases, NIOSH will continue to characterize doses
as acute as the default assumption, since this gives claimants the
benefit of the doubt. As discussed above, this rule, consistent with
the requirement of EEOICPA to calculate probability of causation at the
upper 99 percent credibility limit, gives claimants the benefit of the
doubt with respect to uncertainty. The use of chronic as a default
assumption would reduce the level of probability of causation
calculated for some claims.
One commenter recommended NIOSH-IREP include as an input radiation
doses from nuclides (types of radiation) associated with particle
accelerators.
The radiation weighting factors included in NIOSH-IREP cover the
vast majority of exposures that have occurred or will occur in the
claimant population. Exposures to the most unusual radiation exposure
types, such as protons and other accelerator produced particles, will
be addressed on an individual basis, as specified by NIOSH. It would
not be useful to construct a priori probability distributions for these
radiation types without knowledge of the range of energies likely to be
involved in an actual exposure. Probability distributions developed for
these unusual radiation types will be incorporated into the probability
of causation calculation for affected claimants by DOL through a user-
definable feature of NIOSH-IREP. NIOSH will define the probability
distribution to be applied by DOL and summarize its technical basis in
the dose reconstruction report.
One commenter questioned how NIOSH would know the energies of
neutron doses, since this information will not always be available from
DOE or AWE records.
As discussed in the interim final and final dose reconstruction
rules, NIOSH will assign the energies for claims in which this specific
information is unknown. NIOSH will give the benefit of the doubt to the
claimant in making such assignments, such that the energy selected is
consistent with available information and represents the case most
favorable to the claimant for calculating probability of causation.
[[Page 22306]]
One commenter recommended that NIOSH combine the internal and
external dose reconstruction data into single annual dose values.
It is unclear how this suggested change would be useful. Moreover,
it would rarely be feasible. It would be feasible only when radiation
doses in a given year are limited to a single type of radiation and the
uncertainty distributions for the external and internal doses are
identical.
Several commenters questioned why HHS added a parameter to the
definition of ``covered employee,'' under Sec. 81.4 of the proposed
rule, that is not specified in EEOICPA. HHS specified more narrowly
than EEOICPA that a covered employee, for the purposes of the HHS
rules, is a DOE or AWE employee for whom DOL has requested HHS perform
a dose reconstruction.
This distinction results practically from the separate
responsibilities of DOL and HHS in implementing EEOICPA. DOL is solely
responsible for initially reviewing each claim, evaluating whether the
claim represents a covered employee with a covered illness, and
determining whether or not the claim requires a dose reconstruction.
The only claims DOL will forward to HHS for dose reconstructions are
those involving a covered employee with a cancer not covered by
provisions of the Special Exposure Cohort. Hence, HHS retains its
proposed definition in this rule to be clear that NIOSH will only
conduct dose reconstructions under EEOICPA for the subset of claims
submitted by DOL to HHS for dose reconstructions. This is intended to
avoid the possible confusion and delay that would arise if claimants or
the public were to directly submit to NIOSH requests for dose
reconstructions.
M. Special Exposure Cohort
HHS received several comments that provide recommendations,
criteria, or concerns related to adding members to the Special Exposure
Cohort established under EEOICPA. These comments fall outside the scope
of this rule and address related but separate procedures to be
established by HHS.
As discussed above, HHS is proposing procedures by which it will
consider petitions by classes of employees at DOE or AWE facilities to
be added to the cohort, with the advice of the Advisory Board on
Radiation and Worker Health. These procedures will be published soon in
the Federal Register. The proposed HHS procedures and their
accompanying explanation address the comments received and directly
solicit additional public comments, which HHS will fully consider in
establishing final procedures.
N. DOL Responsibilities Under EEOICPA
HHS received several comments that relate to DOL responsibilities
under EEOICPA and thus fall outside the scope of this rule.
One commenter recommended that claimants be provided with full
documentation of the basis for the probability of causation estimate
determined for their claim by DOL.
DOL will provide the claimant with a recommended decision which
will explain the decision based upon the probability of causation. In
addition, NIOSH will provide the claimant with complete documentation
on the dose reconstruction conducted for the claim, which, together
with the DOL report, provides the claimant with a complete set of the
claim-related data and information used to calculate probability of
causation.
The claimant would not, however, automatically receive
documentation of the formulae and underlying research basis for the
cancer risk models applied to the claim in NIOSH-IREP. This information
is highly technical and complex and is unlikely to be of value to most
claimants. Claimants who desire this information, however, can obtain
it either from NIOSH-IREP, from the NIOSH homepage, or by contacting
NIOSH directly (see contact information above). Some details of IREP
documentation are only available at this time from NCI but will be
incorporated into NIOSH informational resources as soon as possible.
One commenter recommended that claimants be permitted to submit
affidavits in lieu of medical records when necessary.
DOL determines what types of information can constitute medical
evidence of a diagnosis of cancer (see 20 CFR 30.211.). More details
can be obtained by contacting DOL.
One commenter recommended that staff working for contractor support
services offsite from the DOE facility should be treated as covered
employees under EEOICPA. The comment identifies workers providing
offsite laundry services as an example of such support staff. As
discussed above, DOL is responsible for determining whether an
individual is a covered employee within the scope of coverage defined
by Congress in EEOICPA. Individuals who are concerned that certain
employee groups involved in nuclear weapons production or related
activities might be excluded from coverage under EEOICPA should consult
DOL, which makes these determinations.
III. Review and Recommendations of the Advisory Board on Radiation
and Worker Health
As discussed above, the Advisory Board on Radiation and Worker
Health is required by Section 7384(n)(c) of EEOICPA to conduct a
technical review of these HHS guidelines. The Board reviewed the
guidelines during public meetings on January 22-23 and February 5,
2002. In preparation for the meeting, the Board members individually
reviewed the notice of proposed rulemaking as well as the HHS interim
final rule providing the methods of dose reconstruction (42 CFR 82)
that govern the estimation of radiation doses to be used under these
guidelines. The members also reviewed public comments on these rules
and written comments by subject matter experts who evaluated technical
elements of NIOSH-IREP. In addition, NIOSH staff members gave formal
presentations on the HHS rules, implementation procedures, and related
issues during the Board meetings. The transcripts and minutes of these
meetings are included in the NIOSH docket for this rule and are
available to the public.
All of the Board members participated in the technical review of
these guidelines and they unanimously concurred in establishing the
Board findings and recommendations. The Board organized its findings
and recommendations to correspond with the three general questions for
public comment HHS identified in the notice for proposed rulemaking.
The findings and recommendations are provided below, together with
responses by HHS to the recommendations:
Board Comment #1: The Board agrees that the NIOSH guidelines and
procedures for probability of causation determinations have been
developed using the best and most current scientific information
relating radiation exposures to cancer risks. The use of current
recommendations from independent expert bodies lends strength to the
approach proposed by NIOSH. The NIOSH approach also implements the
spirit of concern for nuclear workers that was inherent in the
legislation underlying this compensation program. In this context, the
NIOSH guidelines and procedures provide an appropriate application of
existing science to the compensation process.
HHS Response: No response is necessary, but it may be helpful to
readers to explain the Board's reference to the ``spirit of concern.''
HHS has
[[Page 22307]]
implemented the ``spirit of concern'' to which the Board refers by
consistently and reasonably giving the benefit of the doubt to nuclear
weapons workers, whenever feasible, with respect to policy decisions
and technical procedures involving factual or scientific unknowns and
uncertainty.
Board Comment #2: ``The Board has also noted the differences
between the approach being used in this compensation program and that
of the Atomic Veterans Act. There are significant differences in the
categories of compensation covered by the two acts. In some cases, the
Atomic Veterans Act required primarily that the claimants were present
in a specific area, had one of the specified cancers, and were
therefore compensated. This proposed rule is an effort to address much
more complicated situations and to face the reality that simple
exposure to radiation does not automatically presume the development of
disease. The Board recognizes the excellent efforts of NIOSH staff and
their subject matter experts in bringing the best known current science
to an appropriate method for translating experience gained in the
veterans exposure calculations to this civilian nuclear worker
proposal.''
HHS Response: No response necessary.
Board Comment #3: ``The Board also agrees that the proposed NIOSH
procedures appropriately allow for the incorporation of new scientific
information into the compensation procedures as this new information
becomes available. However, given the limited time that the Board has
had to review the details of the probability of causation procedures
and the potential impact of changes in the NIOSH IREP on compensation
decisions, the Board recommends that the regulations be amended to
formalize the role of the Board in reviewing any substantial changes in
these procedures (i.e., the NIOSH IREP). This change should include
publication of the planned changes in the Federal Register, an
appropriate opportunity for public comment, and then review by this
Board before finalization. Although these actions are included in the
Preamble ``Background,'' (Section III, Subsection I, Paragraph 3) of 42
CFR Part 81, making them part of the rule itself would formalize the
updating process, significantly strengthening assurance that review of
revisions by the Board will occur.''
HHS Response: HHS accepts this recommendation by the Board.
Accordingly, as discussed above in response to public comments on peer-
review, HHS has moved provisions for peer-review involving the Board
from the preamble of the notice of proposed rulemaking into the body of
the rule itself. These provisions can be found at 42 CFR 81.12.
IV. Summary of the Rule
Congress, in enacting EEOICPA, created a new Energy Employees
Occupational Illness Compensation Program to ensure an efficient,
uniform, and adequate compensation system for certain employees.
Through Executive Order 13179, the President assigned primary
responsibility for administering the program to DOL. The President
assigned various technical responsibilities for policymaking and
assistance to HHS. Included among these is promulgation of this rule to
establish guidelines DOL will apply to adjudicate cancer claims for
covered employees seeking compensation for cancer, other than as
members of the Special Exposure Cohort seeking compensation for a
specified cancer. Sections 81.20-81.25 and 81.30 provide guidelines for
determining the probability of causation with respect to all known
cancers.
In the summary below, HHS indicates all the changes in provisions
of this rule made since the notice of proposed rulemaking. These occur
under Secs. 81.10(b) and 81.12.
Introduction
Sections 81.0 and 81.1 briefly describe how this rule relates to
DOL authorities under EEOICPA and the assignment of authority for this
rule to HHS. Section 81.2 summarizes the specific provisions of EEOICPA
directing HHS in the development of this rule.
Definitions
This section of the regulation defines the principal terms used in
this part. It includes terms specifically defined in EEOICPA that, for
the convenience of the reader of this part, are repeated in this
section. The citation to EEOICPA has been revised to reflect the
codification of the Act in the United States Code.
Data Required To Estimate Probability of Causation
Sections 81.5 and 81.6 identify the sources and types of personal,
medical, and radiation dose information that would be required by this
regulation. Claimants will provide personal and medical information to
DOL under DOL regulations 20 CFR Part 30. NIOSH will provide radiation
dose information pursuant to 20 CFR Part 30. NIOSH will develop the
dose information required pursuant to the HHS regulation under 42 CFR
Part 82, which was promulgated on October 5, 2001 as an interim final
rule and is being promulgated as a final rule simultaneously with this
final rule in this issue of the Federal Register. The application of
this personal, medical, and radiation dose information to estimate
probability of causation is described generally under Secs. 81.22--
81.25.
Requirements for Risk Models Used To Estimate Probability of Causation
Sections 81.10 and 81.11 describe the use of cancer risk models and
uncertainty analysis underlying the NIH RadioEpidemiological Tables in
their current, updated form, which is a software program named the
``Interactive RadioEpidemiological Program'' (IREP). NIOSH-IREP, the
version of IREP to be used by DOL to implement this rule, is discussed
extensively in the notice of proposed rulemaking and above. These
sections also propose criteria by which the risk models in NIOSH-IREP
may be changed to ensure that probability of causation estimates
calculated for EEOICPA claimants represent the unique exposure and
disease experiences of employees covered by EEOICPA. In response to
public comments, a criterion discussed above has been added to
Sec. 81.10. This criterion authorizes NIOSH to modify NIOSH-IREP to
account for new understanding of the potential interaction between
cancer risks associated with occupational exposures to chemical
carcinogens and radiation-related cancer effects (see
Sec. 81.10(b)(4)).
Section 81.12 was added in response to comments and describes the
procedure to update NIOSH-IREP. NIOSH may periodically revise NIOSH-
IREP to add, modify, or replace cancer risk models, improve the
modeling of uncertainty, and improve the functionality and user-
interface of NIOSH-IREP. Principal sources of potential improvements in
cancer risk models include new epidemiologic research on DOE employee
populations and periodic updates from scientific committees evaluating
such research (e.g., the Committee on Biological Effects of Ionizing
Radiation).
Improvements may also be recommended by the Advisory Board on
Radiation and Worker Health, scientific reviews relevant to or
addressing this program, public comment, or by DOL, which is the
principal user and hence may require functional changes and
improvements in the user-interface.
Substantive changes to NIOSH-IREP (changes that would substantially
affect
[[Page 22308]]
estimates of probability of causation calculated using NIOSH-IREP,
including the addition of new cancer risk models) will be submitted to
the Advisory Board on Radiation and Worker Health for review. Proposed
changes provided to the Advisory Board for review will also be made
available to the public, which will have opportunity to comment and
have its comments considered by NIOSH and the Board.
To facilitate public participation in updating NIOSH-IREP, NIOSH
will periodically publish a notice in the Federal Register informing
the public of proposed substantive changes to NIOSH-IREP currently
under development, the status of the proposed changes, and the expected
completion dates. NIOSH will also publish a notice in the Federal
Register notifying DOL and the public of the completion of substantive
changes to NIOSH-IREP. In the notice, NIOSH will address relevant
public comments and recommendations from the Advisory Board received by
NIOSH.
Guidelines To Estimate Probability of Causation
Sections 81.20 and 81.21 require DOL to use NIOSH-IREP to estimate
probability of causation for cancers for which probability of causation
estimates can be calculated using available cancer risk models. Section
81.21 also requires DOL to assume carcinoma in situ (ICD-9
26 codes 230-234), neoplasms of uncertain behavior (ICD-9
codes 235-238), and neoplasms of unspecified nature (ICD-9 code 239)
are malignant, for purposes of estimating probability of causation.
---------------------------------------------------------------------------
\26\ ICD-9 is a version of the standard system of classifying
diseases that will be used by IREP. The most recent version of this
system, ICD-10, will not be used because the cancer risk models have
been constructed using ICD-9.
See: The International Classification of Diseases Clinical
Modification (9th Revision) Volume I&II. [1991] Department of Health
and Human Services Publication No. (PHS) 91-1260, U.S. Government
Printing Office, Washington, D.C.
---------------------------------------------------------------------------
Sections 81.22-81.25 provide general guidelines for the use of
NIOSH-IREP and specific applications to accommodate special
circumstances anticipated. The special circumstances include claims in
which: (1) The primary site of a metastasized cancer is unknown; (2)
the subtype of leukemia presented lacks a single, optimal risk model in
NIOSH-IREP; and (3) two or more primary cancers are presented,
requiring further statistical adjustment of probability of causation
estimates calculated using NIOSH-IREP.
The procedure concerning subtypes of leukemia (2) is needed because
of a limitation of the data on Japanese atomic bomb survivors, as
discussed above and in the notice of proposed rulemaking. The general
leukemia model in IREP allows for adjustment for age at exposure, which
is an important modifier of leukemia risk. The data are too sparse,
however, to allow for such an adjustment with respect to specific types
of leukemia, with the exception of chronic myeloid leukemia. Since it
is not possible to determine which factor, age at exposure or leukemia
subtype, is more important to determining probability of causation for
most specific types of leukemia, the guidelines require use of both the
general model and the specific model. The guidelines require DOL to use
the findings of whichever model produces the higher probability of
causation estimate.
Section 81.30 specifies one cancer to be considered non-radiogenic
for the purposes of this rule: chronic lymphocytic leukemia (ICD-9
Code: 204.1). DOL would assign a value of zero to the probability of
causation for a claim based on this type of leukemia. There is general
consensus among the scientific and medical communities that treatment
of this leukemia as non-radiogenic is appropriate, and such treatment
is consistent with other radiation illness compensation programs.
V. Significant Regulatory Action (Executive Order 12866)
This rule is a ``significant regulatory action,'' within the
meaning of Executive Order 12866, because it raises novel or legal
policy issues arising out of the legal mandate established under
EEOICPA. The rule is designed to establish objective guidelines,
grounded in current science, to support DOL in the adjudication of
applicable claims seeking compensation for cancer under EEOICPA. The
guidelines will be applied by DOL to calculate a reasonable,
scientifically supported determination of the probability that a cancer
for which a claimant is seeking compensation was as likely as not
caused by radiation doses incurred in the performance of duty by the
covered employee. The financial cost to the federal government of
applying these guidelines is covered under administrative expenses
estimated by DOL under its rule (see FR 28948, May 25, 2001).
The rule carefully explains the manner in which the regulatory
action is consistent with the mandate for this action under
Sec. 3623(c) of EEOICPA and implements the detailed requirements
concerning this action under this section of EEOICPA. The rule does not
interfere with State, local, and tribal governments in the exercise of
their governmental functions.
The rule is not considered economically significant, as defined in
section 3(f)(1) of the Executive Order 12866. This rule has a
subordinate role in the adjudication of claims under EEOICPA, serving
as one element of an adjudication process administered by DOL under 20
CFR Parts 1 and 30. DOL has determined that its rule fulfills the
requirements of Executive Order 12866 and provides estimates of the
aggregate cost of benefits and administrative expenses of implementing
EEOICPA under its rule (see FR 28948, May 25, 2001).
VI. Regulatory Flexibility Act
The Regulatory Flexibility Act (RFA), 5 U.S.C. 601 et seq.,
requires each agency to consider the potential impact of its
regulations on small entities including small businesses, small
governmental units, and small not-for-profit organizations. HHS
certifies that this rule will not have a significant economic impact on
a substantial number of small entities within the meaning of the RFA.
This rule affects only DOL, HHS, and some individuals filing
compensation claims under EEOICPA. Therefore, a regulatory flexibility
analysis as provided for under RFA is not required.
VII. Paperwork Reduction Act
The Paperwork Reduction Act (PRA), 44 U.S.C. 3501 et seq., requires
an agency to invite public comment on and to obtain OMB approval of any
regulation that requires ten or more people to report information to
the agency or to keep certain records. This rule does not contain any
information collection requirements. It provides guidelines only to the
U.S. Department of Labor (DOL) for adjudicating compensation claims and
thus requires no reporting or record keeping. Information required by
DOL to apply these guidelines is being provided by HHS and by
individual claimants to DOL under DOL regulations 20 CFR 30. Thus, HHS
has determined that the PRA does not apply to this rule.
VIII. Small Business Regulatory Enforcement Fairness Act
As required by Congress under the Small Business Regulatory
Enforcement Fairness Act of 1996 (5 U.S.C. 801 et seq.), the Department
will report to Congress promulgation of this rule. The report will
state that the Department has concluded that this rule is not a ``major
rule'' because it is not likely to result in
[[Page 22309]]
an annual effect on the economy of $100 million or more. However, this
rule has a subordinate role in the adjudication of claims under
EEOICPA, serving as one element of an adjudication process administered
by DOL under 20 CFR Parts 1 and 30. DOL has determined that its rule is
a ``major rule'' because it will likely result in an annual effect on
the economy of $100 million or more.
IX. Unfunded Mandates Reform Act of 1995
Title II of the Unfunded Mandates Reform Act of 1995 (2 U.S.C. 1531
et seq.) directs agencies to assess the effects of Federal regulatory
actions on State, local, and tribal governments, and the private
sector, ``other than to the extent that such regulations incorporate
requirements specifically set forth in law.'' For purposes of the
Unfunded Mandates Reform Act, this rule does not include any Federal
mandate that may result in increased annual expenditures in excess of
$100 million by State, local or tribal governments in the aggregate, or
by the private sector.
X. Executive Order 12988 (Civil Justice)
This rule has been drafted and reviewed in accordance with
Executive Order 12988, Civil Justice Reform and will not unduly burden
the Federal court system. Probability of causation may be an element in
reviews of DOL adverse decisions in the United States District Courts
pursuant to the Administrative Procedure Act. However, DOL has
attempted to minimize that burden by providing claimants an opportunity
to seek administrative review of adverse decisions, including those
involving probability of causation. HHS has provided a clear legal
standard for DOL to apply regarding probability of causation. This rule
has been reviewed carefully to eliminate drafting errors and
ambiguities.
XI. Executive Order 13132 (Federalism)
The Department has reviewed this rule in accordance with Executive
Order 13132 regarding federalism, and has determined that it does not
have ``federalism implications.'' The rule does not ``have substantial
direct effects on the States, on the relationship between the national
government and the States, or on the distribution of power and
responsibilities among the various levels of government.''
XII. Executive Order 13045 (Protection of Children From
Environmental, Health Risks and Safety Risks)
In accordance with Executive Order 13045, HHS has evaluated the
environmental health and safety effects of this rule on children. HHS
has determined that the rule would have no effect on children.
XIII. Executive Order 13211 (Actions Concerning Regulations That
Significantly Affect Energy Supply, Distribution, or Use)
In accordance with Executive Order 13211, HHS has evaluated the
effects of this rule on energy supply, distribution or use, and has
determined that the rule will not have a significant adverse effect on
them.
XIV. Effective Date
The Secretary has determined, pursuant to 5 U.S.C. 553(d)(3), that
there is good cause for this rule to be effective immediately to avoid
undue hardship on and facilitate payment to eligible claimants.
List of Subjects in 42 CFR Part 81
Cancer, Government Employees, Probability of Causation, Radiation
Protection, Radioactive Materials, Workers' Compensation.
Text of the Rule
For the reasons discussed in the preamble, the Department of Health
and Human Services is amending 42 CFR to add Part 81 to read as
follows:
PART 81--GUIDELINES FOR DETERMINING PROBABILITY OF CAUSATION UNDER
THE ENERGY EMPLOYEES OCCUPATIONAL ILLNESS COMPENSATION PROGRAM ACT
OF 2000
Subpart A--Introduction
Sec.
81.0 Background.
81.1 Purpose and Authority.
81.2 Provisions of EEOICPA concerning this part.
Subpart B--Definitions
81.4 Definition of terms used in this part.
Subpart C--Data Required To Estimate Probability of Causation
81.5 Use of personal and medical information
81.6 Use of radiation dose information.
Subpart D--Requirements for Risk Models Used To Estimate Probability of
Causation
81.10 Use of cancer risk assessment models in NIOSH-IREP.
81.11 Use of uncertainty analysis in NIOSH-IREP.
81.12 Procedure for updating NIOSH-IREP.
Subpart E--Guidelines To Estimate Probability of Causation
81.20 Required use of NIOSH-IREP.
81.21 Cancers requiring the use of NIOSH-IREP.
81.22 General guidelines for use of NIOSH-IREP.
81.23 Guidelines for cancers for which primary site is unknown.
81.24 Guidelines for leukemia.
81.25 Guidelines for claims involving two or more primary cancers.
81.30 Non-radiogenic cancers.
Appendix A to Part 81--Glossary of ICD-9 codes and their cancer
descriptions.
Authority: 42 U.S.C. 7384n(c); E.O. 13179, 65 FR 77487, 3 CFR,
2000 Comp., p. 321.
Subpart A--Introduction
Sec. 81.0 Background.
The Energy Employees Occupational Illness Compensation Program Act
(EEOICPA), 42 U.S.C. 7384-7385 [1994, supp. 2001], provides for the
payment of compensation benefits to covered employees and, where
applicable, survivors of such employees, of the United States
Department of Energy, its predecessor agencies and certain of its
contractors and subcontractors. Among the types of illnesses for which
compensation may be provided are cancers. There are two categories of
covered employees with cancer under EEOICPA for whom compensation may
be provided. The regulations that follow under this part apply only to
the category of employees described under paragraph (a) of this
section.
(a) One category is employees with cancer for whom probability of
causation must be estimated or determined, as required under 20 CFR
30.115.
(b) The second category is members of the Special Exposure Cohort
seeking compensation for a specified cancer, as defined under EEOICPA.
The U.S. Department of Labor (DOL) which has primary authority for
implementing EEOICPA, has promulgated regulations at 20 CFR 30.210 et
seq. that identify current members of the Special Exposure Cohort and
requirements for compensation. Pursuant to section 7384(q) of EEOICPA,
the Secretary of HHS is authorized to add additional classes of
employees to the Special Exposure Cohort.
Sec. 81.1 Purpose and Authority.
(a) The purpose of this regulation is to establish guidelines DOL
will apply to adjudicate cancer claims for covered employees seeking
compensation for cancer, other than as members of the Special Exposure
Cohort seeking compensation for a specified cancer. To award a claim,
DOL must first determine that it is at least as likely as not that the
cancer of the employee was caused by radiation doses incurred by the
employee in the performance of
[[Page 22310]]
duty. These guidelines provide the procedures DOL must apply and
identify the information DOL will use.
(b) Section 7384(n)(b) of EEOICPA requires the President to
promulgate these guidelines. Executive Order 13179 assigned
responsibility for promulgating these guidelines to the Secretary of
HHS.
Sec. 81.2 Provisions of EEOICPA concerning this part.
EEOICPA imposes several general requirements concerning the
development of these guidelines. It requires that the guidelines
produce a determination as to whether it is at least as likely as not
(a 50% or greater probability) that the cancer of the covered employee
was related to radiation doses incurred by the employee in the
performance of duty. It requires the guidelines be based on the
radiation dose received by the employee, incorporating the methods of
dose reconstruction to be established by HHS. It requires
determinations be based on the upper 99 percent confidence interval
(credibility limit) of the probability of causation in the
RadioEpidemiological tables published under section 7(b) of the Orphan
Drug Act (42 U.S.C. 241 note), as such tables may be updated. EEOICPA
also requires HHS consider the type of cancer, past health-related
activities, the risk of developing a radiation-related cancer from
workplace exposure, and other relevant factors. Finally, it is
important to note EEOICPA does not include a requirement limiting the
types of cancers to be considered radiogenic for these guidelines.
Subpart B--Definitions
Sec. 81.4 Definition of terms used in this part.
(a) Covered employee, for purposes of this part, means an
individual who is or was an employee of DOE, a DOE contractor or
subcontractor, or an atomic weapons employer, and for whom DOL has
requested HHS to perform a dose reconstruction.
(b) Dose and dose rate effectiveness factor (DDREF) means a factor
applied to a risk model to modify the dose-risk relationship estimated
by the model to account for the level of the dose and the rate at which
the dose is incurred. As used in IREP, a DDREF value of greater than
one implies that chronic or low doses are less carcinogenic per unit of
dose than acute or higher doses.
(c) Dose-response relationship means a mathematical expression of
the way that the risk of a biological effect (for example, cancer)
changes with increased exposure to a potential health hazard (for
example, ionizing radiation).
(d) EEOICPA means the Energy Employees Occupational Illness
Compensation Program Act of 2000, 42 U.S.C. Secs. 7384-7385 [1994,
supp. 2001].
(e) Equivalent dose means the absorbed dose in a tissue or organ
multiplied by a radiation weighting factor to account for differences
in the effectiveness of the radiation in inducing cancer.
(f) External dose means the portion of the equivalent dose that is
received from radiation sources outside of the body.
(g) Interactive RadioEpidemiological Program (IREP) means a
computer software program that uses information on the dose-response
relationship, and specific factors such as a claimant's radiation
exposure, gender, age at diagnosis, and age at exposure to calculate
the probability of causation for a given pattern and level of radiation
exposure.
(h) Internal dose means the portion of the equivalent dose that is
received from radioactive materials taken into the body.
(i) Inverse dose rate effect means a phenomenon in which the
protraction of an exposure to a potential health hazard leads to
greater biological effect per unit of dose than the delivery of the
same total amount in a single dose. An inverse dose rate effect implies
that the dose and dose rate effectiveness factor (DDREF) is less than
one for chronic or low doses.
(j) Linear energy transfer (LET) means the average amount of energy
transferred to surrounding body tissues per unit of distance the
radiation travels through body tissues (track length). Low LET
radiation is typified by gamma and x rays, which have high penetrating
capabilities through various tissues, but transfer a relatively small
amount of energy to surrounding tissue per unit of track length. High
LET radiation includes alpha particles and neutrons, which have weaker
penetrating capability but transfer a larger amount of energy per unit
of track length.
(k) NIOSH means the National Institute for Occupational Safety and
Health, Centers for Disease Control and Prevention, United States
Department of Health and Human Services.
(l) Non-radiogenic cancer means a type of cancer that HHS has found
not to be caused by radiation, for the purposes of this regulation.
(m) Primary cancer means a cancer defined by the original body site
at which the cancer was incurred, prior to any spread (metastasis) to
other sites in the body.
(n) Probability of causation means the probability or likelihood
that a cancer was caused by radiation exposure incurred by a covered
employee in the performance of duty. In statistical terms, it is the
cancer risk attributable to radiation exposure divided by the sum of
the baseline cancer risk (the risk to the general population) plus the
cancer risk attributable to the radiation exposure.
(o) RadioEpidemiological Tables means tables that allow computation
of the probability of causation for various cancers associated with a
defined exposure to radiation, after accounting for factors such as age
at exposure, age at diagnosis, and time since exposure.
(p) Relative biological effectiveness (RBE) means a factor applied
to a risk model to account for differences between the amount of cancer
effect produced by different forms of radiation. For purposes of
EEOICPA, the RBE is considered equivalent to the radiation weighting
factor.
(q) Risk model means a mathematical model used under EEOICPA to
estimate a specific probability of causation using information on
radiation dose, cancer type, and personal data (e.g., gender, smoking
history).
(r) Secondary site means a body site to which a primary cancer has
spread (metastasized).
(s) Specified cancer is a term defined in Sec. 7384(l)(17) of
EEOICPA and 20 CFR 30.5(dd) that specifies types of cancer that,
pursuant to 20 CFR part 30, may qualify a member of the Special
Exposure Cohort for compensation. It includes leukemia (other than
chronic lymphocytic leukemia), multiple myeloma, non-Hodgkin's
lymphoma, renal cancers, and cancers of the lung (other than carcinoma
in situ diagnosed at autopsy), thyroid, male breast, female breast,
esophagus, stomach, pharynx, small intestine, pancreas, bile ducts,
gall bladder, salivary gland, urinary bladder, brain, colon, ovary,
liver (not associated with cirrhosis or hepatitis B), and bone.
(t) Uncertainty is a term used in this rule to describe the lack of
precision of a given estimate, the extent of which depends upon the
amount and quality of the evidence or data available.
(u) Uncertainty distribution is a statistical term meaning a range
of discrete or continuous values arrayed around a central estimate,
where each value is assigned a probability of being correct.
(v) Upper 99 percent confidence interval is a term used in EEOICPA
to mean credibility limit, the probability of causation estimate
determined at the 99th percentile of the range of
[[Page 22311]]
uncertainty around the central estimate of probability of causation.
Subpart C--Data Required To Estimate Probability of Causation
Sec. 81.5 Use of personal and medical information.
Determining probability of causation may require the use of the
following personal and medical information provided to DOL by claimants
under DOL regulations 20 CFR part 30:
(a) Year of birth
(b) Cancer diagnosis (by ICD-9 code) for primary and secondary
cancers
(c) Date of cancer diagnosis
(d) Gender
(e) Race/ethnicity (if the claim is for skin cancer or a secondary
cancer for which skin cancer is a likely primary cancer)
(f) Smoking history (if the claim is for lung cancer or a secondary
cancer for which lung cancer is a likely primary cancer)
Sec. 81.6 Use of radiation dose information.
Determining probability of causation will require the use of
radiation dose information provided to DOL by the National Institute
for Occupational Safety and Health (NIOSH) under HHS regulations 42 CFR
part 82. This information will include annual dose estimates for each
year in which a dose was incurred, together with uncertainty
distributions associated with each dose estimate. Dose estimates will
be distinguished by type of radiation (low linear energy transfer
(LET), protons, neutrons, alpha, low-energy x-ray) and by dose rate
(acute or chronic) for external and internal radiation dose.
Subpart D--Requirements for Risk Models Used To Estimate
Probability of Causation
Sec. 81.10 Use of cancer risk assessment models in NIOSH IREP.
(a) The risk models used to estimate probability of causation for
covered employees under EEOICPA will be based on risk models updated
from the 1985 NIH Radioepidemiological Tables. These 1985 tables were
developed from analyses of cancer mortality risk among the Japanese
atomic bomb survivor cohort. The National Cancer Institute (NCI) and
Centers for Disease Control and Prevention (CDC) are updating the
tables, replacing them with a sophisticated analytic software program.
This program, the Interactive RadioEpidemiological Program (IREP)\1\,
models the dose-response relationship between ionizing radiation and 33
cancers using morbidity data from the same Japanese atomic bomb
survivor cohort. In the case of thyroid cancer, radiation risk models
are based on a pooled analysis of several international cohorts\1a\.
---------------------------------------------------------------------------
\1\ NIOSH-IREP is available for public review on the NIOSH
homepage at: www.cdc.gov/niosh/ocas/ocasirep/html.
\1a\ Ron E, Lubin JH, Shore RE, et al. ``Thyroid cancer after
exposure to external radiation: a pooled analysis of seven
studies.'' Radiat. Res. 141:259-277, 1995.
---------------------------------------------------------------------------
(b) NIOSH will change the risk models in IREP, as needed, to
reflect the radiation exposure and disease experiences of employees
covered under EEOICPA, which differ from the experiences of the
Japanese atomic bomb survivor cohort. Changes will be incorporated in a
version of IREP named NIOSH-IREP, specifically designed for
adjudication of claims under EEOICPA. Possible changes in IREP risk
models include the following:
(1) Addition of risk models to IREP, as needed, for claims under
EEOICPA (e.g., malignant melanoma and other skin cancers)
(2) Modification of IREP risk models to incorporate radiation
exposures unique to employees covered by EEOICPA (e.g., radon and low
energy x rays from employer-required medical screening programs,
adjustment of relative biological effectiveness distributions based on
neutron energy).
(3) Modification of IREP risk models to incorporate new
understanding of radiation-related cancer effects relevant to employees
covered by EEOICPA (e.g., incorporation of inverse dose-rate
relationship between high LET radiation exposures and cancer;
adjustment of the low-dose effect reduction factor for acute
exposures).
(4) Modification of IREP risk models to incorporate new
understanding of the potential interaction between cancer risk
associated with occupational exposures to chemical carcinogens and
radiation-related cancer effects.
(5) Modification of IREP risk models to incorporate temporal, race
and ethnicity-related differences in the frequency of certain cancers
occurring generally among the U.S. population.
(6) Modifications of IREP to facilitate improved evaluation of the
uncertainty distribution for the probability of causation for claims
based on two or more primary cancers.
Sec. 81.11 Use of uncertainty analysis in NIOSH-IREP.
(a) EEOICPA requires use of the uncertainty associated with the
probability of causation calculation, specifically requiring the use of
the upper 99% confidence interval (credibility limit) estimate of the
probability of causation estimate. As described in the NCI
document,2 uncertainty from several sources is incorporated
into the probability of causation calculation performed by NIOSH-IREP.
These sources include uncertainties in estimating: radiation dose
incurred by the covered employee; the radiation dose-cancer
relationship (statistical uncertainty in the specific cancer risk
model); the extrapolation of risk (risk transfer) from the Japanese to
the U.S. population; differences in the amount of cancer effect caused
by different radiation types (relative biological effectiveness or
RBE); the relationship between the rate at which a radiation dose is
incurred and the level of cancer risk produced (dose and dose rate
effectiveness factor or DDREF); and, the role of non-radiation risk
factors (such as smoking history).
---------------------------------------------------------------------------
\2\ Draft Report of the NCI-CDC Working Group to Revise the 1985
NIH Radioepidemiological Tables, May 31, 2000, p. 17-18, p. 22-23.
---------------------------------------------------------------------------
(b) NIOSH-IREP will operate according to the same general protocol
as IREP for the analysis of uncertainty. It will address the same
possible sources of uncertainty affecting probability of causation
estimates, and in most cases will apply the same assumptions
incorporated in IREP risk models. Different procedures and assumptions
will be incorporated into NIOSH-IREP as needed, according to the
criteria outlined under Sec. 81.10.
Sec. 81.12 Procedure to update NIOSH-IREP.
(a) NIOSH may periodically revise NIOSH-IREP to add, modify, or
replace cancer risk models, improve the modeling of uncertainty, and
improve the functionality and user-interface of NIOSH-IREP.
(b) Revisions to NIOSH-IREP may be recommended by the following
sources:
(1) NIOSH,
(2) The Advisory Board on Radiation and Worker Health,
(3) Independent reviews of NIOSH-IREP or elements thereof by
scientific organizations (e.g., National Academy of Sciences),
(4) DOL,
(5) Public comment.
(c) NIOSH will submit substantive changes to NIOSH-IREP (changes
that would substantially affect estimates of probability of causation
calculated using NIOSH-IREP, including the addition of new cancer risk
models) to the Advisory Board on Radiation and Worker Health for
review. NIOSH will obtain such review and address any recommendations
of the review before completing and implementing the change.
[[Page 22312]]
(d) NIOSH will inform the public of proposed changes provided to
the Advisory Board for review. HHS will provide instructions for
obtaining relevant materials and providing public comment in the notice
announcing the Advisory Board meeting, published in the Federal
Register.
(e) NIOSH will publish periodically a notice in the Federal
Register informing the public of proposed substantive changes to NIOSH-
IREP currently under development, the status of the proposed changes,
and the expected completion dates.
(f) NIOSH will notify DOL and publish a notice in the Federal
Register notifying the public of the completion and implementation of
substantive changes to NIOSH-IREP. In the notice, NIOSH will explain
the effect of the change on estimates of probability of causation and
will summarize and address relevant comments received by NIOSH.
(g) NIOSH may take into account other factors and employ other
procedures than those specified in this section, if circumstances arise
that require NIOSH to implement a change more immediately than the
procedures in this section allow.
Subpart E--Guidelines To Estimate Probability of Causation
Sec. 81.20 Required use of NIOSH-IREP.
(a) NIOSH-IREP is an interactive software program for estimating
probability of causation for covered employees seeking compensation for
cancer under EEOICPA, other than as members of the Special Exposure
Cohort seeking compensation for a specified cancer.
(b) DOL is required to use NIOSH-IREP to estimate probability of
causation for all cancers, as identified under Secs. 81.21 and 81.23.
Sec. 81.21 Cancers requiring the use of NIOSH-IREP.
(a) DOL will calculate probability of causation for all cancers,
except chronic lymphocytic leukemia as provided under Sec. 81.30, using
NIOSH-IREP.
(b) Carcinoma in situ (ICD-9 codes 230-234), neoplasms of uncertain
behavior (ICD-9 codes 235-238), and neoplasms of unspecified nature
(ICD-9 code 239) are assumed to be malignant, for purposes of
estimating probability of causation.
(c) All secondary and unspecified cancers of the lymph node (ICD-9
code 196) shall be considered secondary cancers (cancers resulting from
metastasis of cancer from a primary site). For claims identifying
cancers of the lymph node, Table 1 in Sec. 81.23 provides guidance for
assigning a primary site and calculating probability of causation using
NIOSH-IREP.
Sec. 81.22 General guidelines for use of NIOSH-IREP.
DOL will use procedures specified in the NIOSH-IREP Operating Guide
to calculate probability of causation estimates under EEOICPA. The
guide provides current, step-by-step instructions for the operation of
IREP. The procedures include entering personal, diagnostic, and
exposure data; setting/confirming appropriate values for variables used
in calculations; conducting the calculation; and, obtaining,
evaluating, and reporting results.
Sec. 81.23 Guidelines for cancers for which primary site is unknown.
(a) In claims for which the primary cancer site cannot be
determined, but a site of metastasis is known, DOL will calculate
probability of causation estimates for various likely primary sites.
Table 1, below, indicates the primary cancer site(s) DOL will use in
NIOSH-IREP when the primary cancer site is unknown.
Table 1
Primary cancers (ICD-9 codes 3) for which probability of
causation is to be calculated, if only a secondary cancer site is
known. ``M'' indicates cancer site should be used for males only, and
``F'' indicates the cancer site should be used for females only. A
glossary of cancer descriptions for each ICD-9 code is provided in
Appendix A to this part.
---------------------------------------------------------------------------
\3\ The International Classification of Diseases Clinical
Modification (9th Revision) Volume I&II. [1991] Department of Health
and Human Services Publication No. (PHS) 91-1260, U.S. Government
Printing Office, Washington D.C.
------------------------------------------------------------------------
Secondary cancer (ICD-9 code) ICD-9 code of likely primary cancers
------------------------------------------------------------------------
Lymph nodes of head, face and 141, 142 (M), 146 (M), 149 (F), 161 (M),
neck (196.0). 162, 172, 173, 174 (F), 193 (F).
Intrathoracic lymph nodes 150 (M), 162, 174 (F).
(196.1).
Intra-abdominal lymph nodes 150 (M), 151 (M), 153, 157 (F), 162, 174
(196.2). (F), 180 (F), 185 (M), 189, 202 (F).
Lymph nodes of axilla and 162, 172, 174 (F).
upper limb (196.3).
Inguinal and lower limb lymph 154 (M), 162, 172, 173 (F), 187 (M).
nodes (196.5).
Intrapelvic lymph nodes 153 (M), 154 (F), 162 (M), 180 (F), 182
(196.6). (F), 185 (M), 188.
Lymph nodes of multiple sites 150 (M), 151 (M), 153 (M), 162, 174 (F).
(196.8).
Lymph nodes, site unspecified 150 (M), 151, 153, 162, 172, 174 (F), 185
(196.9). (M).
Lung (197.0)................. 153, 162, 172 (M), 174 (F), 185 (M), 188
(M), 189.
Mediastinum (197.1).......... 150 (M), 162, 174 (F).
Pleura (197.2)............... 150 (M), 153 (M), 162, 174 (F), 183 (F),
185 (M), 189 (M).
Other respiratory organs 150, 153 (M), 161, 162, 173 (M), 174 (F),
(197.3). 185 (M), 193 (F).
Small intestine, including 152, 153, 157, 162, 171, 172 (M), 174
duodenum (197.4). (F), 183 (F), 189 (M).
Large intestine and rectum 153, 154, 162, 174 (F), 183 (F), 185 (M).
(197.5).
Retroperitoneum and 151, 153, 154 (M), 157, 162 (M), 171, 174
peritoneum (197.6). (F), 182 (F), 183 (F).
Liver, specified as secondary 151 (M), 153, 154 (M), 157, 162, 174 (F).
(197.7).
Other digestive organs 150 (M), 151, 153, 157, 162, 174 (F), 185
(197.8). (M).
Kidney (198.0)............... 153, 162, 174 (F), 180 (F), 185 (M), 188,
189, 202 (F).
Other urinary organs (198.1). 153, 174 (F), 180 (F), 183 (F), 185 (M),
188, 189 (F).
Skin (198.2)................. 153, 162, 171 (M), 172, 173 (M), 174 (F),
189 (M).
Brain and spinal cord (198.3) 162, 172 (M), 174 (F).
Other parts of nervous system 162, 172 (M), 174 (F), 185 (M), 202.
(198.4).
Bone and bone marrow (198.5). 162, 174 (F), 185 (M).
Ovary (198.6)................ 153 (F), 174 (F), 183 (F).
Suprarenal gland (198.7)..... 153 (F), 162, 174 (F).
Other specified sites (198.8) 153, 162, 172 (M), 174 (F), 183 (F), 185
(M), 188 (M).
------------------------------------------------------------------------
[[Page 22313]]
(b) DOL will select the site producing the highest estimate for
probability of causation to adjudicate the claim.
Sec. 81.24 Guidelines for leukemia.
(a) For claims involving leukemia, DOL will calculate one or more
probability of causation estimates from up to three of the four
alternate leukemia risk models included in NIOSH-IREP, as specified in
the NIOSH-IREP Operating Guide. These include: ``Leukemia, all types
except CLL'' (IDC-9 codes: 204-208, except 204.1), ``acute lymphocytic
leukemia'' (ICD-9 code: 204.0), and ``acute myelogenous leukemia''
(ICD-9 code: 205.0).
(b) For leukemia claims in which DOL calculates multiple
probability of causation estimates, as specified in the NIOSH-IREP
Operating Guide, the probability of causation estimate DOL assigns to
the claim will be based on the leukemia risk model producing the
highest estimate for probability of causation.
Sec. 81.25 Guidelines for claims including two or more primary
cancers.
For claims including two or more primary cancers, DOL will use
NIOSH-IREP to calculate the estimated probability of causation for each
cancer individually. Then DOL will perform the following calculation
using the probability of causation estimates produced by NIOSH-IREP:
EQUATION 1
Calculate: 1-[{1 x PC1} x {1-PC2} x . . . x
{1-PCn}] = PCtotal,
where PC1 is the probability of causation for one of the
primary cancers identified in the claim, PC2 is the
probability of causation for a second primary cancer identified in the
claim, and PCn is the probability of causation for the nth
primary cancer identified in the claim. PCtotal is the
probability that at least one of the primary cancers (cancers 1 through
``n'') was caused by the radiation dose estimated for the claim when
Equation 1 is evaluated based on the joint distribution of
PC1, . . ., PCn.\4\ DOL will use the probability
of causation value calculated for PCtotal to adjudicate the
claim.
Sec. 81.30 Non-radiogenic cancers
The following cancers are considered non-radiogenic for the
purposes of EEOICPA and this part. DOL will assign a probability of
causation of zero to the following cancers:
(a) Chronic lymphocytic leukemia (ICD-9 code: 204.1)
(b) [Reserved]
------------
\4\ Evaluating Equation 1 based on the individual upper 99th
percentiles of PC1, . . ., PCn approximates
the upper 99th percentile of PCtotal whenever
PC1, . . ., PCn are highly related, e.g., when
a common dose-reconstruction is the only non-negligible source of
uncertainty in the individual PCi's. However, this
approximation can overestimate it if other sources of uncertainty
contribute independently to the PC1, . . .,
PCn, whereas treating the joint distribution as fully
independent could substantially underestimate the upper 99th
percentile of PCtotal whenever the individual
PCi's are positively correlated.
Appendix A to Part 81--Glossary of ICD-9 Codes and Their Cancer
Descriptions \1\
------------------------------------------------------------------------
ICD-9 code Cancer description
------------------------------------------------------------------------
140....................................... Malignant neoplasm of lip.
141....................................... Malignant neoplasm of
tongue.
142....................................... Malignant neoplasm of major
salivary glands.
143....................................... Malignant neoplasm of gum.
144....................................... Malignant neoplasm of floor
of mouth.
145....................................... Malignant neoplasm of other
and unspecified parts of
mouth.
146....................................... Malignant neoplasm of
oropharynx.
147....................................... Malignant neoplasm of
nasopharynx.
148....................................... Malignant neoplasm of
hypopharynx.
149....................................... Malignant neoplasm of other
and ill-defined sites
within the lip, oral
cavity, and pharynx.
150....................................... Malignant neoplasm of
esophagus.
151....................................... Malignant neoplasm of
stomach.
152....................................... Malignant neoplasm of small
intestine, including
duodenum.
153....................................... Malignant neoplasm of colon.
154....................................... Malignant neoplasm of
rectum, rectosigmoid
junction, and anus.
155....................................... Malignant neoplasm of liver
and intrahepatic bile
ducts.
156....................................... Malignant neoplasm of gall
bladder and extrahepatic
bile ducts.
157....................................... Malignant neoplasm of
pancreas.
158....................................... Malignant neoplasm of
retroperitoneum and
peritoneum.
159....................................... Malignant neoplasm of other
and ill-defined sites
within the digestive organs
and peritoneum.
160....................................... Malignant neoplasm of nasal
cavities, middle ear, and
accessory sinuses.
161....................................... Malignant neoplasm of
larynx.
162....................................... Malignant neoplasm of
trachea, bronchus and lung.
163....................................... Malignant neoplasm of
pleura.
164....................................... Malignant neoplasm of
thymus, heart, and
mediastinum.
165....................................... Malignant neoplasm of other
and ill-defined sites
within the respiratory
system and intrathoracic
organs.
170....................................... Malignant neoplasm of bone
and articular cartilage.
171....................................... Malignant neoplasm of
connective and other soft
tissue.
172....................................... Malignant melanoma of skin.
173....................................... Other malignant neoplasms of
skin.
174....................................... Malignant neoplasm of female
breast.
175....................................... Malignant neoplasm of male
breast.
179....................................... Malignant neoplasm of
uterus, part unspecified.
180....................................... Malignant neoplasm of cervix
uteri.
181....................................... Malignant neoplasm of
placenta.
182....................................... Malignant neoplasm of body
of uterus.
183....................................... Malignant neoplasm of ovary
and other uterine adnexa.
184....................................... Malignant neoplasm of other
and unspecified female
genital organs.
185....................................... Malignant neoplasm of
prostate.
186....................................... Malignant neoplasm of
testis.
[[Page 22314]]
187....................................... Malignant neoplasm of penis
and other male genital
organs.
188....................................... Malignant neoplasm of
urinary bladder.
189....................................... Malignant neoplasm of kidney
and other unspecified
urinary organs.
190....................................... Malignant neoplasm of eye.
191....................................... Malignant neoplasm of brain.
192....................................... Malignant neoplasm of other
and unspecified parts of
nervous system.
193....................................... Malignant neoplasm of
thyroid gland.
194....................................... Malignant neoplasm of other
endocrine glands and
related structures.
195....................................... Malignant neoplasm of other
and ill-defined sites.
196....................................... Secondary and unspecified
malignant neoplasm of the
lymph nodes.
197....................................... Secondary malignant neoplasm
of the respiratory and
digestive organs.
198....................................... Secondary malignant neoplasm
of other tissue and organs.
199....................................... Malignant neoplasm without
specification of site.
200....................................... Lymphosarcoma and
reticulosarcoma.
201....................................... Hodgkin's disease.
202....................................... Other malignant neoplasms of
lymphoid and histiocytic
tissue.
203....................................... Multiple myeloma and other
immunoproliferative
neoplasms.
204....................................... Lymphoid leukemia
205....................................... Myeloid leukemia.
206....................................... Monocytic leukemia.
207....................................... Other specified leukemia.
208....................................... Leukemia of unspecified cell
type.
------------------------------------------------------------------------
1 The International Classification of Diseases Clinical Modification
(9th Revision) Volume I&II. [1991] Department of Health and Human
Services Publication No. (PHS) 91-1260, U.S. Government Printing
Office, Washington, D.C.
Dated: April 10, 2002.
Tommy G. Thompson,
Secretary, Department of Health and Human Services.
[FR Doc. 02-10764 Filed 4-30-02; 8:45 am]
BILLING CODE 4160-17-P