December 23, 1999
- DRAFT -
NATIONAL ECONOMIC COUNCIL
OCCUPATIONAL ILLNESS COMPENSATION FOR
DEPARTMENT OF ENERGY CONTRACTOR PERSONNEL
REPORT OF TASK GROUP 1
January, 2000
CONTENTS
· EXECUTIVE SUMMARY
· BACKGROUND
· Nuclear Weapons Production and DOE Operations
· Radiation Exposures and Cancer Risk
· Chemical Exposures
· FINDINGS
· Summary of Major Findings from DOE Epidemiologic Studies
· Summary of Findings Related to Chemical Hazards at DOE Sites
· Summary of Findings from Special Radiation Workers Monitoring Programs:
Los Alamos Plutonium Workers
Rocky Flats High RAD Workers Program
US Transuranium and Uranium Registries
· Summary of Findings from Other Surveillance Programs:
Epidemiologic Surveillance Program
Computerized Accident/Incident Reporting System (CAIRS)
· Initial Results from the Former Workers Program
· REFERENCES
· APPENDICES
· APPENDIX 1: Summary of Epidemiologic Studies
· APPENDIX 2: References for the DOE Epidemiologic Studies
· APPENDIX 3: Chemical Contaminants at DOE
· APPENDIX 4: Radiation Workers Monitoring Programs
· APPENDIX 5: Epidemiologic Surveillance Program and CAIRS
· APPENDIX 6: Initial Results from Former Workers Studies
· APPENDIX 7: List of Panel Members
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EXECUTIVE SUMMARY
This report summarizes the activities and results of both completed health studies and ongoing health surveillance programs that are conducted at the US Department of Energy (DOE). The DOE is a government-owned, contractor-operated Federal government agency. Studies reviewed here focus on this contractor workforce during their work producing nuclear weapons.
Historically, the primary focus of DOE health studies was limited to health effects related to exposure to ionizing radiation. Toxic chemicals (other than radionuclides) have been studied only to a limited extent. This report does not postulate what diseases might result from these exposures. Rather, it relies solely on adverse health outcome information and radiation exposure data from peer-reviewed studies as well as technical government reports.
The panel did not consider nor evaluate other non-DOE populations with occupational radiation exposures such as shipyard workers, medical personnel, or atomic bomb survivors. Establishing and measuring causal links between exposures and illness was not considered to be within the scope of the mandate of this panel.
There is evidence that current and former contractor workers at DOE nuclear weapons production facilities are at increased risk of illness from occupational exposures associated with the production of nuclear weapons. The strength of the evidence varies with some evidence showing a strong association with employment in specific facilities while other evidence is at best suggestive of an occupational association.
The primary focus of the studies concerning the health status of these workers has been mortality studies. The evidence presented in the studies reviewed by the panel clearly provides strong evidence in the form of statistically significant excesses of specific cancers at a number of DOE facilities. In addition, a number of studies showed statistically significant positive trends by radiation dose. This evidence, considering that many studies identified excess cancers that did not reach the levels of statistical significance and that several studies did show statistically significant cancer excesses with extended follow-up periods, demonstrates a relationship of work at nuclear weapons facilities and illness. Cancers for which strong evidence exists include lung, brain, bladder, myeloma, leukemia and other lymphatic cancers, stomach, respiratory, laryngeal, and trachea. The identification of excess of some types of cancers at some facilities and other types of cancers at other facilities is not unexpected based on the vast differences in production processes and thus exposures at the various DOE facilities.
Information presented to the panel concerning morbidity studies and medical surveillance programs for current and former DOE contract workers also present significant evidence that these workers have suffered material impairment of health as a result of performing their duties in the production of nuclear weapons. This evidence must be viewed with caution for several reasons. The former worker medical surveillance program is in its initial phase with only preliminary results available. The participants are self selected and therefore caution must be exercised in drawing any conclusions as to the health status of the overall population of former workers. However, the results presented do provide strong evidence that participating former workers at some facilites have experienced significant health impairment in the form of nonmalignant lung diseases consistent with exposures to asbestos and silica, hearing impairment, and beryllium disease. The mortality studies have also show strong evidence that workers at several facilities have experienced nonmalignant lung diseases.
The strength of the evidence is limited by several factors. First and foremost are the limitations associated with most mortality studies such as difficulties in determining individual exposures, limited cohort size, and limited follow-up time. Population-based studies also have a number of inherent limitations including their inability to answer questions about the relationship between and individual's illness and the workers' occupational exposures. Another factor that limits the strength of the presented evidence is the numerous potentially confounding exposures and the lack of industrial hygiene data to account for these exposures. The scope of the available studies and information present significant limitations to the evidence. A number of DOE facilities have not been included in these studies and the available studies have not included all workers. Finally, since most of the studies were limited to the identification of the underlying cause of death, many cancers and other occupational diseases may not have been accounted for in the available information.
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BACKGROUND
On July 15, 1999, President Clinton issued a Memorandum to the Secretaries of Defense, Labor, and Energy, the Attorney General, the Director of the Office of Management and Budget, and the Assistant to the President for Economic Policy regarding occupational illness compensation for DOE contractor personnel. The Memorandum indicated the Administration's intent to submit legislation to create a program to give DOE contractor employees with chronic beryllium disease (CBD) and beryllium sensitivity compensation benefits similar to those available to Federal employees. Such legislation was submitted to Congress on November 17, 1999. In addition, the July 15th Memorandum established an interagency review led by the National Economic Council (NEC) to assess, by March 31, 2000, whether there are other illnesses that warrant inclusion in this program and how this should be accomplished.
In determining whether and how other illnesses should be included in this program, three tasks were designated. The first task (Task 1) is the subject of this report to the NEC.
From October 1999, through January, 2000, a panel of experts from a wide spectrum of federal agencies (Appendix 7) met to address the following questions:
What is the evidence that current and former contractor workers at DOE facilities are at increased risk of illness resulting from exposures to occupational hazards uniquely associated with nuclear weapons production?
How strong is this evidence?
To answer these questions, the federal expert panel examined and evaluated information and data from a variety of sources including current and historical exposure hazards at DOE facilities which are unique to nuclear weapons production, as well as epidemiologic, other health studies and surveillance activities conducted among DOE contractor workers. Although data from other radiation exposed cohorts, most notably shipyard workers, were presented to the panel, the results of these studies are not included in this report due primarily to the limited focus and charge of this panel.
NUCLEAR WEAPONS PRODUCTION & DOE OPERATIONS
The Department of Energy and its predecessor agencies, principally the Manhattan Engineering District and the Atomic Energy Commission, have been engaged primarily in an extensive industrial enterprise to build and test nuclear weapons. For more than half a century, DOE has owned and its contractors have operated a nationwide network of heavy industrial sites as well as research laboratories involved in every aspect of weapons production from the refining of raw materials to the eventual testing of the bombs, and ultimately to the management of the weapons stockpile and the environmental consequences of nuclear production and testing (Ref. 1). It has been estimated that 5.5 trillion dollars (in 1996 dollars) have been spent since 1940 on US nuclear weapons and weapons-related programs (Ref. 2) and that upwards of 600,000 workers were involved in the construction, maintenance, operations, and scientific activities at DOE-owned facilities.
Figure 2 (Appendix 3) summarizes the process used to produce nuclear weapons. At each stage of the nuclear weapons cycle, from refining the raw materials to weapons assembly and finishing, to waste management and disposal, the principal materials used and primary exposures are listed. This figure is by no means a complete inventory of the potential health hazards that exist during the complex process of producing a nuclear weapon. For a more complete understanding of the potential chemical hazards involved in its operations, DOE has published a description of chemical vulnerabilities at its sites (Ref. 3). In addressing its charge, the NEC Task 1 panel examined evidence of illnesses from two classes of exposure: radiation and chemicals.
RADIATION EXPOSURES & CANCER RISK
Throughout the history of weapons production, exposure to external ionizing radiation was viewed as the hazard of greatest concern to the health of the nuclear weapons workforce. Great effort and expense were devoted to assessing dose principally to external radiation, but also to internal doses and neutrons as well. The greatest body of radiation exposure data comes from the dosimeters worn by DOE employees to measure external ionizing radiation. These were primarily film badges until the early 1970s when solid state thermo-luminescent detectors (TLDs) were adopted. The time period between badge readings was largely determined by the occupational standards of the time. In the 1950s the occupational limit was a weekly limit, in the 1960s a quarterly limit was established and since the 1970s the primary limit is an annual limit. Each site has been expected to determine who needs to wear a dosimeter and how often to exchange dosimeters based on working conditions at that site.
Radiation measurements are converted to radiation dose through the application of correction and quality factors to approximate the biologic effect of external gamma radiation at a depth of 1 cm in tissue (deep dose equivalent [DDE]). Prior to 1993 DOE required that internal dose be reported as annual effective dose equivalent (AEDE), which is the summation for all tissues and organs of the products of the dose equivalent calculated to be received by each tissue or organ during the specified year from all internal depositions multiplied by the appropriate weighting factor. Since 1993 internal dose has been required to be reported as committed effective dose equivalent (CEDE), which is the sum of the dose equivalents to various tissues in the body, each multiplied by the appropriate weighting factor, that will be accumulated over the next 50 years.
Dose records go as far back as the establishment of the Manhattan Engineering District in late 1942. These records have been used in various contexts to assess exposures of the DOE workforce and to evaluate their health. Radiation protection and control programs constituted the main focus of worker safety and health efforts at DOE sites. Prior to 1974 annual doses of less than 10 mSv were not required to be reported to the AEC. These records are available at the sites and have been used in health studies at selected sites. Starting in 1974 the AEC began collecting data on the number of individuals with measurable exposure, which is the subset of all monitored individuals who receive a measurable exposure (greater than limit of detection for the monitoring system). Many personnel are monitored as a matter of prudence and may not receive a measurable exposure. The number of individuals with measurable exposure is a better indicator of the exposed workforce. Appendix 4 (Table 7) lists the results of radiation monitoring from 1974 through 1997.
The historic distribution of dose for the DOE workforce is shown in Figure 1. The decline in average dose between 1986 and 1991 was due to the cessation of nuclear weapons production and the shutdown of numerous reactors used in their production
Figure 1. Historic Dose Distribution for the DOE Workforce
Based on the estimates shown above, average dose from 1945 to 1997 was about 1 mSv per year. The BEIR V report of the National Research Council provides a model for estimating excess cancer mortality based on a continuous adult working lifetime (47 year) exposure of 10 mSv per year. Using this model with an estimated average annual exposure of 1 mSv for the DOE cohort of monitored workers, an excess of 288 cancers per 100,000 might be expected. This number could be as low as 215 or as high as 546 per 100,000 cancers in excess of the 20,560 cancer deaths per 100,000 population expected in the absence of occupational radiation exposures, a one to three percent excess.
Note: The BEIR model estimates 2,880 excess cancers for continuous exposure to 10 mSv/y from age 18 to age 65 for a population of 100,000 males. Applying this to the DOE work force being exposed to 1 mSv/y this converts to 2880/10 = 288 cancers per 100,000 exposed workers.
CHEMICAL EXPOSURES
It has been estimated that more than 40,000 different chemicals are present throughout the DOE complex, and some, such as solvents and degreasers, are used in vast quantities. Toxicological information is available on most of the major chemicals to which DOE workers are exposed; however, little is known about the actual levels of worker exposure to these materials. DOE does not maintain a centralized repository of information on exposures to individual chemicals.
To further complicate matters, exposures are often to mixtures of substances making a risk assessment based on the known toxicological profiles of these materials nearly impossible.
While chemical hazards have not been either well documented or studied at DOE, a number of reports suggest, either directly or indirectly, that chemical hazards pose a significant health risk to both current and former DOE workers (Ref. 4-6). These risks may exceed those posed by radionuclides.
An example of a non-radiogenic chemical exposure is beryllium, a hazard that is specifically excluded from this report (since it is already covered under separate legislation). Exposure by DOE contractor workers and the resulting health conditions associated with beryllium exposure (Ref. 7) served as a basis for the Presidential Memorandum of July 15, 1999, and as the origin of this report.
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FINDINGS
SECTION 1: SUMMARY OF MAJOR FINDINGS FROM DOE EPIDEMIOLOGIC STUDIES
Background
Mortality studies of DOE workers began in 1964 and have continued uninterrupted through the present. The patterns of mortality have been the primary focus of these studies, particularly cancers from ionizing radiation exposure. More than 40 studies of DOE contractor workers have been completed to date; there are more than 20 additional studies underway. The studies cover fourteen out of nineteen of the principal facilities of the US weapons complex but excludes dozens of private facilities that supplied DOE and the entire navy nuclear program (which is excluded by Executive Order). The studies concentrated primarily on production workers. At those sites where construction workers were employed as part of a prime contract, they would have been included in the site's study, but not analyzed as a separate group. Construction workers employed by the Zia Company at the Los Alamos National Laboratory were the one exception where a separate analysis of their mortality experience is reported. The studies include workers employed from 1944-86 with results emphasizing those employed during the period of greatest production activity across the DOE weapons complex between 1944 and 1979. Due to changes in the DOE's mission with the cessation of the nuclear arms race and various international arms limitations agreements, results of these historical studies no longer reflect current workplace conditions.
When excess mortality was noted or a trend identified for a specific cause of death, special in-depth studies were undertaken. Specific exposures that have been studied include external ionizing radiation, internal ionizing radiation from plutonium and polonium, tritium and uranium dust. Additionally metallic mercury, nickel and nickel oxides, phosgene, and epoxy resins have also been studied. The nature and degree of exposures varied greatly from site to site depending on the operations and production at a given site. Historically, white males were the primary subjects of these studies. More recent studies and most new studies examine the impact of exposures to both non-white and female workers.
Human data on cancer induction by radiation are extensive. The most comprehensive studies involve the survivors of the atomic bombings of Hiroshima and Nagasaki, X-rayed tuberculosis patients, and persons exposed during treatment for ankylosing spondilitis, cervical cancer, and tinea capitis. Cancers either frequently or occasionally associated with radiation include leukemia, thyroid, female breast, lung, stomach, colon, esophagus, bladder, ovary and myeloma.
Other lifestyle factors (smoking and lung cancer, diet and colon cancer) and occupational exposures (leukemia and benzene, bladder cancer and dyes) are potential confounders for some of these cancers. Age at exposure, dose, dose rate and other factors may also influence the results of a particular population-based study as well as modify an individual's risk for disease.
Findings: (PANEL MEMBERS ARE WORKING ON THESE CONCLUSIONS)
· Overall, DOE production workers had significantly lower age-adjusted death rates compared to the U.S. general population for all causes of death combined; there were only two exceptions.
· The relationship between mortality and exposure to ionizing radiation has been investigated for some but not all of the DOE cohorts. An increase in the risk of dying from specific conditions has been associated with increased exposure to external radiation exposure in seven cohort studies and to internal exposure in two studies.
· When positive trends for mortality by level of ionizing radiation were observed, they were always based on small numbers of deaths (less than five) among workers with the highest lifetime radiation doses.
· There was no clear excess risk of mortality for any specific condition among the groups that were studied. The observed higher mortality rates for specific conditions were limited to specific facilities, subgroups of workers, and specific time periods of employment.
· Special studies of workers with brain cancer, multiple myeloma, malignant melanoma, non-malignant respiratory diseases, and malignant respiratory diseases were pursued. Except for non-malignant respiratory disease among Fernald workers, the special studies did not find specific occupational exposures associated with the conditions.
A summary of studies and findings by site is found in Appendix 1. Appendix 1 also includes a listing of the Standardized Mortality Ratios (SMRs) for all causes of death for US nuclear weapons workers (Table 1) as well as a summary of statistically significant elevated SMRs for selected causes of death for US nuclear weapons workers, by site (Table 2). Table 3 shows the statistically significant SMRs for each cause of death among DOE contractor employees.
A listing of both the peer-reviewed and other publications relating to epidemiologic studies of DOE workers is found in Appendix 2 of this report.
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SECTION 2: SUMMARY OF FINDINGS RELATED TO CHEMICAL HAZARDS AT DOE SITES
Background
Table 4 (Appendix 3) provides an overview of the chemical hazards that are commonly cited in either environmental studies around DOE sites and/or in health studies of DOE workers. Table 4 represents a very small fraction of the estimated 40,000 chemicals that have been used at DOE facilities. Only a very small proportion of these chemicals has been examined in health studies of DOE workers. Table 5 and Figure 2 (Appendix 3) provide a summary of the principal chemicals, processes and sites used in the production of nuclear weapons.
Findings from epidemiologic studies:
· Mercury workers - studies of exposure to metallic mercury were associated with clinical neurologic abnormalities in the most highly exposed group.
· Centrifuge workers - an incidence of bladder cancer was observed among gas centrifuge manufacturing workers. Although epoxy resins and solvents were commonly used in the gas centrifuge manufacturing process, the observed higher incidence of bladder cancer among gas centrifuge workers was not associated with exposure to these substances. In phase I, the incidence rate was 7 times that expected. In phase II it was not found to be greater than for a local comparison population.
· Welders - the most recent study of welders revealed higher risk of death from lung cancer, prostate cancer, and stomach ulcers. The risk for lung cancer was not related to nickel exposure. Thorium was not evaluated in the first Oak Ridge welders study. The welders updated study has been requested from CER and will be evaluated (it is cited in the reference list).
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SECTION 3: SUMMARY OF FINDINGS FROM SPECIAL RADIATION WORKERS MONITORING PROGRAMS
Background
DOE supports three specialized monitoring programs or studies of a relatively small number of workers with the highest exposures to ionizing radiation from radionuclides and/or external sources. These special programs include a tissue registry for post-mortem analyses of workers with known occupational exposure levels to radionuclides, periodic medical follow-up for plutonium-exposed workers (average dose 1,250 mSv), and a program of cancer screening for workers with the highest doses of external radiation (dose greater than 200 mSv). These specialized programs are described in Appendix 4.
Findings:
· Specialized radiation worker studies have generally not shown unusual numbers or types of illnesses commonly associated with radiation exposure, even among workers with known high body burdens of radionuclides.
· One case each of osteosarcoma and lung fibrosis have been diagnosed among workers exposed to plutonium. Osteosarcoma is a rare cancer and is of interest since plutonium is known to deposit in the bone.
· Among the 244 causes of death in the tissue registries, a number of cancer deaths from causes associated with radiation exposure were identified. In addition, six confirmed cases of mesothelioma among DOE workers exposed to asbestos have been documented. Table 6 (Appendix 4) provides a complete listing.
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SECTION 4: SUMMARY OF FINDINGS FROM OTHER SURVEILLANCE PROGRAMS
Background
DOE supports two injury and illness surveillance programs. The Epidemiologic Surveillance Program collects illness information from occupational medicine programs. The Computerized Accident/Incident Reporting System (CAIRS) is a centralized database that collects all contractor reports of injuries, illnesses, and other accidents. It is based on Department of Labor requirements for reporting these events. Data from DOE investigations of these reports are used to generate performance indicators used by the DOE to provide estimates of dollar loses due to work-related injuries, illnesses, and accidental property damage. Recent summaries of epidemiologic surveillance and CAIRS data are presented in Appendix 5.
Findings:
· CAIRS provides an enumeration of lost-time injuries and illnesses throughout the DOE system
· The Epidemiologic Surveillance Program reports cases of occupational illnesses among DOE workers that are consistent with Sentinel Health Events of Occupational origin [SHE(O)] reported in the medical literature.
· Both of these DOE-maintained surveillance systems allow for the identification of current illnesses and injuries in its workforce.
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SECTION 5: INITIAL RESULTS FROM THE FORMER WORKERS PROGRAM
Background
In response to a Congressional mandate, DOE recently initiated a medical surveillance program tailored specifically to examine former DOE workers felt to be at high risk for occupationally-related illnesses. Preliminary results from these studies are presented in Appendix 6.
Findings:
· Initially medical screening has found a relatively high proportion of abnormalities on chest X-ray among selected groups of former workers.
· Of the 882 individuals screened to date, 148 (17%) have ILO category 1/0 or greater perfusion on their chest X-ray indicating the presence of a pneumoconiosis.
· There were other findings but data were too preliminary to include. Conditions that are being studied include exposures to heavy metals, hearing loss, beryllium exposure and exposures to solvents and mixed chemicals.
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REFERENCES
Ref. 1 Linking Legacies. Connecting the Cold War Nuclear Weapons Production Processes to their Environmental Consequences. DOE/EM-0319 US Department of Energy. January 1997.
Ref. 2 Atomic Audit, the Costs and Consequences of U.S. Nuclear Weapons since 1940. S.I. Schwartz, editor. The Brookings Institution, Washington, D.C. 1998.
Ref. 3 Chemical Safety Vulnerability Working Group Report, 1994, U.S. Department of Energy, DOE/EH-0396P; DOE/EH-0398P
Ref. 4 Hazards Ahead: Managing Cleanup Worker Health and Safety at the Nuclear Weapons Complex. US Congress. Office of Technology Assessment. OTA-BP-O-85. Washington, D.C.: U.S. Government Printing Office, February 1993.
Ref. 5 Comparative Carcinogenicity of Ionizing Radiation and Chemicals. National Council on Radiation Protection and Measurements. NCRP Report No 96. Bethesda, MD. March 1, 1989.
Ref. 6 Radiation Protection in the Mineral Extraction Industry. National Council on Radiation Protection and Measurements. NCRP Report No 118. Bethesda, MD November 30, 1993.
Ref. 7 Beryllium Biomarkers: Application of Immunologic, Inflammatory, and Genetic Tools. Lee S. Newman. Pages 285-300 in Biomarkers: Medical and Workplace Applications. Joseph Henry Press. 1998, Washington D.C.
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APPENDIX 1
Background
Epidemiology is the study of the distribution and determinants of disease in human populations. The distribution of disease is considered in relation to time, place, and person. Relevant population characteristics include the age, race, and sex distribution of a population, as well as other characteristics related to health, such as social characteristics (e.g., income and education), occupation, susceptibility to disease, and exposure to specific agents. Determinants of disease include the causes of disease, as well as factors that influence the risk of disease. There are three major study designs that are used in studies of workers and communities.
Study Designs
Cohort Studies. The cohort study design is a type of epidemiologic study frequently used to examine occupational exposures within a defined workforce. A cohort study requires a defined population that can be classified as being exposed or not exposed to an agent of interest, such as radiation or chemicals that influence the probability of occurrence of a given disease. Characterization of the exposure may be qualitative (e.g., high, low, or no exposure) or very quantitative (e.g., radiation measured in Sieverts (Sv), chemicals in parts per million [ppm]). Surrogates for exposure, such as job titles, are frequently used in the absence of quantitative exposure data.
Individuals enumerated in the study population are tracked for a period of time, their vital status (dead or alive) is determined at the time of the study, and cause of death is sought for the deceased member of the study population. In general, overall rates of death and cause-specific rates of death have been assessed for workers at DOE sites. Death rates for the exposed worker population are compared with death rates of workers who did not have the exposure (internal comparison), or compared with expected death rates based on the U.S. population or state death rates (external comparison). If the rates of death differ from what is expected, an explanation is sought to account for the differences such as exposure to a carcinogen at work. In cohorts where the exposure has not been characterized, excess mortality can be identified, but these deaths cannot be attributed to a specific exposure, and additional studies may be warranted. More recent studies have looked at disease endpoints other than death, such as overall and cause-specific cancer incidence (newly diagnosed) rates.
Most cohort studies at DOE sites have been historical cohort studies, that is, the exposure occurred some time in the distant past. These studies rely on past records to document exposure. This type of study can be problematic if exposure records are incomplete or were destroyed. Cohort studies require populations that have been followed for many (20 to 30) years. They are generally difficult to conduct and are very expensive. These studies are not well suited to studying diseases that are rare. Cohort studies do, however, provide a direct estimate of the risk of death from a specific disease, and allow an investigator to look at many disease end points.
Case-Control Studies. The case-control study design starts with the identification of persons with the disease of interest (case) and a suitable comparison (control) population of persons without the disease. Controls must be persons who are at risk for the disease and are representative of the population that generated the cases. The selection of an appropriate control group is often quite problematic. Cases and controls are then compared with respect to the proportion of individuals exposed to the agent of interest. Case-control studies require fewer persons than cohort studies, and therefore, are usually less costly and less time consuming, but are limited to the study of one disease (or cause of death). These types of studies are well suited for the study of rare diseases and are generally used to examine the relationship between a specific disease and exposure.
Proportionate Mortality Studies. In situations where the total worker population at risk has not been identified, mortality rates cannot be calculated and risk cannot be estimated. When only deaths or illnesses are known there is an alternative approach. The approach is to examine the proportional distribution of deaths from specific conditions in the study group relative to the same condition in the U.S. general or regional population. The resulting index is the Proportional Mortality Ratio (PMR). This approach is not powerful although it is useful in rapidly screening worker populations to identify conditions that may reflect occupational exposures.
Standardized Mortality Ratio: The standardized mortality rate (SMR) is the ratio of the number of deaths observed in the study population to the number of expected deaths. The expected number of deaths is based on a reference (or comparison population). Death rates for the U.S. (or state) population are most frequently used as the comparison to obtain expected rates. An SMR of 100 indicates a similar risk of disease in the study population compared with the reference population. An SMR greater than 100 indicates excess risk of disease in the study population compared with the reference group, and an SMR less than 100 indicates a deficit of disease.
MAJOR FINDINGS
Because of the large number of studies and the many comparisons involved, only statistically significant higher rates and positive dose-response trends are reported. They are shown below in italics. Statistical significance reflects estimates that are based on a sufficient number of deaths to be judged reliable. Statistical significance by itself is not proof that the condition is due partly or in entirely to workplace exposures. Special studies were identified with a bold type face.
Fernald "Feed Materials Production Center" (Reference prefix - FMPC)
From 1951 to 1989 Fernald processed uranium and thorium into fabricated metal products for use in the defense programs. There were 4,014 white male employees included in the single cohort mortality study. For deaths through 1989, the death rate for stomach cancer among salaried white males was higher than the rate for the U.S. population. Hourly males had higher rates for all cancer combined, lung cancer, and motor vehicle accidents.
For all males there was a positive association between chronic respiratory disease mortality, excluding respiratory cancers, and internal dose equivalent. An independent study of the same population reported positive trends for both acute and chronic respiratory disease illness. Acute respiratory illness include influenza and pneumonia; chronic illnesses include emphysema and bronchitis.
The Fernald study will be updated with new deaths through 1997. It will also include additional workers as well as an in-depth assessment of radiation, chemical exposures, and cigarette smoking.
Hanford Site (Reference prefix - HAN)
The Hanford Site produced reactor fuel, operated nine reactors and five chemical separation facilities, and fabricated plutonium components for the weapons program. Hanford site workers have been the subjects of numerous mortality studies beginning in 1964. The first study compared longevity of workers with that of their brothers and sisters. No differences were seen among radiation exposed and non-exposed workers. Within Washington state for the period 1950-1971, atomic workers, presumed to be Hanford site workers, were reported to have higher proportions of death due to multiple myeloma, cancer of the pancreas, and cancer of the colon than were seen in the general population of Washington. A similar proportional analysis that included the average lifetime occupational dose of ionizing radiation found that the dose was higher than expected for multiple myeloma, cancer of the pancreas, cancer of the brain and central nervous system, kidney cancer, lung cancer, colon cancer, myeloid leukemia and lymphoma. In addition to the specific cancers, three broad categories: "all cancer combined," "bone marrow cancers," and "reticuloendothelial cancers" were identified as radiation sensitive cancers. This method of analysis was questioned because it included only deceased workers in the comparison group. Several independent reviewers of the average lifetime dose methodology concluded that the method was inappropriate although the data did support a conclusion that radiation was associated with cancer of the pancreas and multiple myeloma. These early studies were not based on mortality rates and were used as the basis for more formal, in-depth cohort studies.
The earliest cohort studies reported on about 13,000 white males who were employed two or more years at Hanford with deaths through 1974, 1977 and 1978. Gradually the study population increased to include all workers without regard to length of employment at Hanford, about 44,000 employees with deaths through 1981 and 1986. Over time, Hanford workers have had mortality rates substantially below the general U.S. population rates with the following exceptions: Among female workers not monitored for external radiation, accidents, poisonings, and violence are greater than expected. Monitored females had a higher rate of death from diseases of the musculoskeletal system and connective tissues than expected. Unmonitored males had higher death rates for cancer of the pancreas and miscellaneous solid tumors than expected.
Among the Hanford workers, the relationship between the death rate and the external radiation dose has been studied repeatedly. Positive trends in the death rate with increasing exposure have been reported for white males and for white males and females combined. These trends were for deaths due to cancer of the liver, cancer of the pancreas, Hodgkin's disease, and multiple myeloma. In one study a positive trend for female genital cancers was noted.
In the early 1980s white males with a lifetime occupational dose of 20 mSv or more were known to have a small excess risk from lung cancer. A study of tobacco use in this group determined that the excess could not explained by smoking cigarettes.
Estimates of the increased risk of death per unit radiation exposure were made to test whether or not the radiation protection standards of the past adequately protected workers. One approach was to look at the upper limit of the risk per unit radiation and compare it to that for other populations. The absolute excess risk for leukemia per million person-years per 10 mSv, based on atomic bomb survivor data, as calculated by ICRP and BEIR committees, is approximately 1-2 deaths. For Hanford, the 95% upper confidence limit is about 4-5 deaths.
Age-at-exposure effect. The idea of sensitive age-at -exposure groups first appeared in 1977. Examination of the average lifetime dose equivalent for specific cancers compared to non-cancer deaths supported two sensitive age-at-exposure groups; under age 25 years and over age 45 years. Three subsequent analyses by the same research team reported this age sensitivity. It was variously reported as over age 58 years, over age 62 years, and age 55-65 years. A recent analysis reported a significant positive trend for all cancer combined by level of cumulative dose equivalent for monitored workers age 75 years and older who were born before 1905. A special case-control study of multiple myeloma at four DOE facilities reported that the most sensitive age-at-exposure group was age 45 years and older.
From 1981 through 1993 a number of models were proposed to estimate the cancers among Hanford workers that could be attributed to ionizing radiation. The attributable proportions from the modeling ranged from 5% to 50%.
Lawrence Livermore National Laboratory (Reference prefix - LLNL)
Lawrence Livermore National Laboratory (LLNL) is a multi-purpose laboratory that conducts research and development for the weapons program and for stockpile stewardship. The incidence rate of malignant melanoma was higher for 5,100 LLNL employees than for the population of the region based on 19 cases diagnosed from 1972-77. Work involving exposure to ionizing radiation was not associated with a diagnosis of melanoma; working as a chemist was. In 1984, based on a review of records for persons with and without melanoma, occupational factors were reaffirmed as being associated with melanoma risk. Later, when the incidence rates for LLNL workers were recalculated for the period 1969-80, higher rates were found for some cancers in addition to malignant melanoma. The incidence rates for salivary gland cancer and rectal cancer, among female Laboratory workers, were above the rates for the region. For male laboratory workers, other nervous system tumors, excluding brain tumors, were higher than expected.
Thirty one laboratory workers with malignant melanoma and a control group were interviewed about personal and occupational factors that might be associated with the disease. Five factors were more common than expected among persons with malignant melanoma. These were judged to contribute independently to a persons risk of melanoma. They were exposure to radioactive materials, work at Site 300, exposure to volatile photographic chemicals, participant at the Pacific Test Site, and chemist duties. The most recent interview study of 69 cases and an equal number of controls found that differences in personal factors, genetics, and recreational use of the outdoors were consistent with what is known about malignant melanoma of the skin. Only occupational exposure to alcohols, out of 39 industrial exposures examined, was more common among persons with melanoma.
Several special studies of the microscopic features of the melanoma tumors indicated that the tumor thickness among laboratory workers was significantly less than for individuals that did not work at LLNL, at least up to the time when the concern became public in 1977. These data on microscopic features were taken as evidence of medical over diagnosis of tumors at LLNL. A greater proportion of workers hired before 1962, who were engineers, particularly electrical engineers, had dark moles or pigmented nevi that are associated with a high risk of malignant melanoma.
Linde Air Products (Reference prefix - LIND)
Linde Air Products processed the highest grade Belgian Congo pitchblende and domestic uranium ores into uranium compounds from 1943 through 1949. Mortality rates through 1979 for the 995 white males were compared to U.S. rates and regional mortality rates. The results for the U.S. and region were similar. The rates for six cause of death categories were higher than expected: all causes of death combined, cancer of the larynx, all circulatory diseases, arteriosclerotic heart disease, respiratory diseases, and in particular, pneumonia.
Los Alamos National Laboratory (Reference prefix - LANL)
Los Alamos National Laboratory (LANL) is a multi-purpose laboratory where nuclear weapons were designed, developed and tested; and small quantities of plutonium metal were produced. The first and longest running study at LANL was for two groups of workers with the highest exposures to plutonium. The two groups are 224 white males within the Manhattan Project and 26 workers with plutonium depositions in 1944-45. Deaths rates have been analyzed at various points in time. The study of 224 males reported that no death rate was greater than expected for deaths through 1980. For the 26, the overall mortality rate and all causes of cancer rate were below what was expected based on the U.S. general population through 1987.
Among 6,970 LANL females, those classified as radiation workers had a high death rate for suicide through 1981. This was not related to duration of employment, plutonium exposure, or marital status.
A special study of malignant melanoma cases between 1969 and 1978 revealed that the rate of newly diagnosed melanomas was similar to that for New Mexico in general. Detailed review of work histories for 15 cases did not reveal any important characteristics of workplace exposures that differed from a comparison group.
The Los Alamos Zia Company was the construction contractor at LANL. The Zia study included 5,424 workers who were monitored for exposure to either plutonium or external ionizing radiation. For all workers combined, the mortality rates through 1984 were greater than the U.S. rates for stomach cancer, senility and ill-defined conditions, all injuries, all accidents, and in particular, motor vehicle accidents. Hispanic males did not share the high rate for senility and ill-defined conditions. Non-Hispanic males had higher rates for deaths from all causes, all cancers, lung cancer, all circulatory diseases, and all non malignant respiratory diseases.
No cause of death was reported with a positive trend for radiation exposure in the Zia Company study group.
In the most recent LANL study, based on 15,727 white males, no cause of death was higher than the U.S. rates through 1990.
Within the most recent LANL study, positive trends have been reported for external ionizing radiation and cancers of the brain and central nervous system, cancer of the esophagus, and Hodgkin's disease. Among workers not exposed to plutonium two additional positive trends were detected for kidney cancer and lymphocytic leukemia.
Mallinckrodt Chemical Works (Reference prefix - MCW)
The Uranium Division of Mallinckrodt Chemical Works (MCW) processed uranium ore and concentrate to pure uranium oxide and uranium metal from 1942 to 1966. The MCW study included 2,514 white males. No death rates were greater than the U.S. rates through 1993.
A positive trend was found for kidney cancer by level of exposure to cumulative external radiation.
Mound Facility (Reference prefix - MND)
Mound was the site for the development of non-nuclear and nuclear components for weapons using polonium and beryllium, and for recycling tritium. Mound also produced plutonium-238 electric generators for spacecraft. Three mortality studies of white males have been conducted at Mound. A preliminary study examined the mortality of 4,697 white male employees of the Mound Facility through 1979. Overall, no death rate was higher than expected based on US general population rates. Among men first hired between 1943 and 1945, the rates for all causes of death combined, all cancers combined, cancer of the rectum, lung cancer, all respiratory diseases, and all injuries were higher than expected. The higher rates for all causes of death combined and lung cancer were reported for men who worked less than two years at Mound. Among men hired through 1959, cancer of the prostate was high among those who worked more than 5 years. In the first published study of 4,182 white males, no death rates were higher than the U.S. rates through 1979. Analysis of deaths through 1983 for 4,402 white males reported that the rates for all cancers combined, cancer of the lung, and cancer of the rectum were high only among workers hired in1944 through 1945 (World War II hires). The higher death rates in World War II hires did not appear to be due to radiation exposure.
Workers who were monitored for external exposure to ionizing radiation had a positive trend for cancer of the lymphopoietic and hematopoietic system due primarily to the individual positive trends for all leukemia combined, particularly for lymphatic and myeloid leukemia that make up the larger category. Males monitored for polonium uptake did not have positive trends for any cause of death through 1983.
Oak Ridge Reservation (Reference prefix - OR)
Oak Ridge Reservation (ORR combined). There have been several studies that considered Oak Ridge workers as a single entity. The first study looked at the mortality experience of 28,008 white male World War II workers employed at three ORR facilities. Compared to the rates for the U.S. population through 1980, the workers had higher rates for all causes of death combined; lung cancer; tuberculosis; mental, psychoneurotic, and personality disorders; cerebrovascular disease; diseases of the respiratory system, particularly emphysema; and all accidents, particularly motor vehicle accidents. Because these workers were not engaged in military service during wartime, it is not possible to know whether or not these conditions reflect occupational exposures or underlying health conditions that would have excluded them from military service.
The second study updated mortality through 1984 and broadened the base of the first study to include 106,020 workers at all four ORR facilities. Mortality from all causes of death combined and all cancers combined were in close agreement with U.S. rates. There were substantial differences in death rates among workers at the various Oak Ridge plants, particularly the rates for lung cancer, leukemia and other lymphatic cancer that are discussed below.
Within the second study, data for 28,374 workers at X-10 and Y-12 were analyzed for trends. Positive trends were reported with increasing external radiation dose for all causes of death combined and all cancers combined.
There have been three published studies of brain cancer across the four ORR facilities. Of 26 chemicals included in the exposure analysis, none were positively associated with brain cancer. There were no positive trends for brain cancer with increasing external radiation dose and internal dose as measured by the lung dose. Although workers with brain cancer were more likely than other workers to have worked at ORR more than 20 years, there was no trend with years worked. A medical history of epilepsy or head injury was not associated with brain cancer.
Mortality data through 1974 and through 1989 were analyzed for about 1,059 white male welders at the Oak Ridge Reservation. No death rate was higher than the U.S. rate through 1974. When deaths through 1989 were considered, welders had more lung cancer, cancer of the prostate, and gastric ulcers. The risk of each cause was different among the facilities. The risk of lung cancer among welders exposed to nickel oxides did not differ from non-exposed welders.
Oak Ridge National Laboratory - (Reference prefix - ORX). The Oak Ridge National Laboratory (ORNL) is a multi-purpose laboratory that was involved in reactor operations, chemical separations, and research. The first cohort study of ORNL considered 8,375 white males and deaths through 1977. No cause of death was greater than expected based on the U.S. general population. A follow up study reported that the death rate from leukemia was greater than the U.S. rate through 1984, particularly among workers monitored for internal radiation contamination. In the most recent study of death rates through 1990, none of the four causes of death reported: all causes of death combined, all cancers combined, lung cancer, and leukemia, were higher than the U.S. rate.
Although the leukemia rate through 1984 was high, there was no positive trend in the death rate by level of cumulative external ionizing radiation dose. A positive trend was reported for all cancers combined by level of cumulative external dose.
A recent study of deaths through 1990 reported that radiation doses received after age 45 years predicts the all cancers combined mortality rate; another study notes this finding for those who were age 65 years and older at exposure.
Oak Ridge Y-12 Plant (Reference prefix - ORY). Y-12 was involved in uranium enrichment and fabrication of nuclear weapons components. The original Y-12 mortality study was updated twice. The first study included 18,869 white males who ever worked at the plant and mortality through 1974. The second study was restricted to 6,781 men who worked at least 30 days with mortality through 1979. The most recent study was expanded to include 10,597 nonwhite workers and females with deaths through 1990.
The death rate for lung cancer was higher than the U.S. rate in the most recent two studies. An elevated lung cancer death rate was first evident for deaths occurring between 1955 and 1964. The rate continued to increase for deaths occurring between 1975 and 1979 followed by a declining rate.
Analysis of deaths through 1979 did not reveal positive trends for any cause of death with either external or internal exposure to ionizing radiation. The most recent study did not include radiation measurements.
Between 1953 and 1963 the Y-12 Plant used metallic mercury in a process to produce large quantities of enriched lithium. There were 5,663 workers categorized by exposure based on results of urinalysis data. Analysis of deaths through 1978 revealed no differences in the mortality patterns for mercury exposed workers as a whole, workers with the highest mercury exposures, and workers employed more than a year in a mercury process. There were 502 mercury workers involved in a clinical study. Clinical measurements revealed some deficiencies in neurological function particularly among those workers with the highest exposures, but not with the duration of exposure. A follow up study of 219 of the original subjects in the 1990s revealed that some neurologic effects were still detectable.
During the early operation of the Y-12 plant from 1942-1947, a group of 694 male workers was exposed to phosgene gas on a chronic basis and 106 males received acute exposures along with 91 females. A control group of 9,280 workers who also worked at Y-12 during the same era, but who did not have phosgene exposure, was also described. All groups were followed through the end of 1978 with particular interest in respiratory diseases and lung cancer. There was no evidence for increased mortality from respiratory diseases in this group.
Oak Ridge K-25 Gaseous Diffusion Plant (Reference prefix - ORK). The K-25 plant was a center for uranium enrichment for nuclear weapons and commercial uranium fuel. The death rates through 1989 for 35,712 workers were the focus of the study. White male workers had high rates relative to U.S. general population rates for all causes of death combined; cancer of the respiratory system, particularly lung cancer; bone cancer; mental disorders, all respiratory diseases, particularly pneumonia; symptoms, senility, and ill-defined conditions; all external causes of death, particularly accidents and specifically motor vehicle accidents. White females had a high rate for symptoms, senility, and ill-defined conditions.
Powdered nickel was used at the Oak Ridge K-25 gaseous diffusion plant in the production of the barrier material used to separate and enrich uranium. Death rates for 814 nickel workers who fabricated the barriers were compared to 1,600 controls. There were no differences in the death rates for the exposed and non exposed workers by cause of death through 1972. A later study compared the mortality through 1977 of the nickel workers and 7,552 non exposed workers. There were no causes of death with a rate higher than the U.S. rate and no differences between exposed and non exposed workers.
Epoxy resins and solvents were common exposures among K-25 gas centrifuge workers. A total of 263 workers with the most exposure were compared with 271 employees with no exposure at the plant during the same time period. The centrifuge workers reported five incident bladder cancers versus none reported by the non-centrifuge group. A specific causative agent for the increase in bladder cancer was not identified. The centrifuge workers are in a medical monitoring program
Pantex Plant (Reference prefix - PTX)
Pantex is the center for high-explosives component fabrication for nuclear weapons and for nuclear weapons disassembly and storage. The cohort mortality study of the Pantex Plant included mortality through 1978 among 3,564 white male employees. There were no causes of death with rates greater than those seen in the U.S. general population.
Portsmouth Gaseous Diffusion Plant (Reference prefix - PTS)
Mortality among 5,733 white male employees at the Portsmouth Gaseous Diffusion Plant was studied through 1982. No cause-specific death rate was greater than expected based on the U.S. general population rates. Based on urinalysis data for uranium content, two groups of workers were identified with relatively higher potential for exposure to uranium compounds. The mortality experience of these two groups was essentially the same as the total population of workers. This study was expanded to include all workers employed through 1991. The study included 8,877 employees and their mortality was studied through 1991. In September 1999, the study investigators reported that the death rates for various cancers did not exceed those for the U.S. population. Among the 6,827 workers exposed to uranium hexafluoride, special emphasis was on the death rates for all causes of death combined, all cancers combined, stomach cancer, hematopoietic cancer, and lung cancer. The rate for each of these was no larger than the comparable U.S. rate. There were no positive trends for these four cause of death groups by increasing urine counts. Among 1,446 workers exposed to fluorine or fluoride, and 465 exposed to nickel; the rate for all causes of death combined and all cancers combined did not exceed the U.S. rates.
Rocketdyne/Atomics International workers (Reference prefix - RAI)
The Rocketdyne/Atomics International radiation study included 4,563 employees monitored for exposure to external ionizing radiation. The mortality study considered external exposure to ionizing radiation and internal deposition of radioactive materials. Compared to U.S. general population through 1994, no cause of death rates were greater than expected.
Positive trends in the rates by level of exposure to external radiation were reported for all cancers combined, cancers of the blood and blood forming tissues, and lung cancer. In the Rocketdyne/Atomics International chemical study they found no relationship between asbestos exposure and lung cancer mortality among the radiation-monitored workers.
Positive trends in the rates by level of internal radiation dose were reported for cancers of the blood and blood forming tissues, and cancers of the upper aerodigestive tract.
Rocky Flats (Reference prefix - RFP)
For the 7,112 white males who ever worked at Rocky Flats, only the death rate for benign and unspecified neoplasm of the brain was greater than in the U.S. rate. Among the 5,413 Rocky Flats white males who worked at the site for at least 2 years, there was a higher rate of benign tumors and tumors of unspecified nature when comparing them with the U.S. general population through 1979; these were brain tumors. A study of 16 of the 22 known brain tumor cases through 1977 found no associations with exposure to internally deposited plutonium, external ionizing radiation or occupation. Independent review of occupational dosimetry records and pathologic examination of tissues from six of these workers led to the conclusion that none were radiation-related.
There were no positive trends for any cause of death by level of external or internal radiation exposure, although workers with a higher body burden (internal deposition) of plutonium had a higher rate for all causes of death combined and for all lymphopoietic cancers combined when compared to those with a smaller burden.
A subsequent reanalysis of the data for the 5,413 Rocky Flats workers found a positive trend for all non-cancers across external exposure groups due to a strong positive trend for circulatory diseases.
Savannah River Site (Reference prefix - SRS)
The Savannah River Site produced, purified and processed plutonium, tritium, and other radioisotopes for the nuclear weapons program. Three cancer incidence studies were conducted among active workers beginning with new cancer cases diagnosed in 1956 and ending in 1974, 1980, and 1983 respectively. There were no overall cancer incidence rates or rates by radiation exposure group that were higher than U.S. rates. Special investigations were conducted for (1) leukemia, and later for (2) leukemia, prostate cancer, and lung cancer. Preliminary results from the later study indicate that radiation monitored workers in the higher exposed group had a higher death rate for chronic lymphocytic leukemia than expected.
The first complete mortality study included 9,860 white male Savannah River workers. A higher rate of leukemia than the U.S. general population through 1980 was reported. This was concentrated among hourly workers employed before 1955 who worked from 5 to 15 years. Review of the plant records and job duties of all workers who died from leukemia indicated that seven, half of the leukemia deaths, had the potential for some exposure to industrial solvents. The leukemia death rate through 1986 was higher than expected only for those deaths occurring from 1965 through 1969. Preliminary findings from the most recent study of a larger group of workers reported that the leukemia mortality rate was not higher than the U.S. rate through 1995.
A positive trend was seen for leukemia mortality and external dose for deaths through 1986.
Multi-Site study: All Department of Energy facilities (Greater than 5 rem Study) (Reference - MULTI96)
This is a study of 1,404 DOE and DOE contractor employees who received 50 mSv or more external radiation dose in any calendar year during employment at the facilities. Within this special group of workers, no causes of death were above that expected based on the U.S. general population. The addition of Navy nuclear shipyard workers to the study did not change the findings.
Multi-Site study: Multiple Myeloma (Reference - MULTI98b)
The study included 98 cases of multiple myeloma and 391 controls from the populations of the Hanford Site, Los Alamos National Laboratory, Oak Ridge National Laboratory, and the Savannah River Plant. The risk of multiple myeloma was linked to external ionizing radiation exposure after age 45 years.
Multi-Site study: Uranium dust study (Reference - MULTI95b)
This special study of uranium dust exposure and lung cancer among workers employed between 1943 and 1947 was conducted at the Tennessee Eastman, Y-12, Fernald, and Mallinckrodt facilities. There were 787 cases of lung cancer in the study. The risk of lung cancer did not increase with increasing radiation dose. The authors did suggest that there was a trend in risk for worker exposure after age 45 years. Analysis by external radiation dose and exposure to thorium, radium, and radon were uninformative.
Multi-Site study: Uranium Millers (Reference prefix - MULTI83)
The front end of the uranium fuel cycle includes the milling of uranium ore. The most recent National Institute for Occupational Safety and Health study of uranium millers included 2,002 males from seven plants on the Colorado Plateau. These men worked at least one year since 1940 and had never worked in uranium mining. Compared to the U.S. population through 1977, there were only two causes of death that had higher rates: non malignant respiratory diseases, particularly the chronic respiratory conditions, and miscellaneous accidents.
________________
Table 1. SMRs for all Causes of Death for US Nuclear Weapons Workers
Table 2. Statistically Significant Elevated SMRs for Selected Causes of Death for US
Nuclear Weapons Workers, by Site
Table 3
Statistically Significant Standardized Mortality Ratios (SMR) for Each Cause of
Death Among DOE Contractor Employees
APPENDIX 2
MORBIDITY AND MORTALITY STUDIES AT THE NUCLEAR WEAPONS COMPLEX
FMPC83. Wilson J. An epidemiological investigation of non-malignant respiratory disease among workers at a uranium mill. Doctoral Dissertation, University of North Carolina, Chapel Hill, School of Public Health, 1983.
FMPC96. Cragle DL, Watkins JP, Ingle JN, Robertson-DeMers K, Tankersley WG, West CM. Mortality among a cohort of white male workers at a uranium processing plant: Fernald Feed Materials Production Center, 1951-1989. Center for Epidemiologic Research, Oak Ridge Institute for Science and Education, Oak Ridge, Tennessee, 1996.
FMPC99. Ritz B. Radiation exposure and cancer mortality in uranium processing workers. Epidemiology 1999; 10:531-538.
HAN71. Mancuso TF, Sanders BS, Brodsky A. Study of the lifetime health and mortality experience of employees of AEC contractors, Part I. Methodology and some preliminary findings limited to mortality for Hanford employees. Volume III of the proceedings of the sixth annual Health Physics Society topical symposium, Richland, Washington November 25, 1971.
HAN77. Mancuso TF, Stewart A, Kneale GW. Radiation exposures of Hanford workers dying from cancer and other causes. Health Physics 1977; 33:369-385.
HAN78a. Anderson TW. Radiation exposures of the Hanford workers: A critique of the Mancuso, Stewart and Kneale report. Health Physics 1978; 35:743-750.
HAN78b. Kneale GW, Stewart A, Mancuso TF. Reanalysis of data relating to the Hanford study of the cancer risks of radiation workers. Proceedings of the IAEA symposium on late biological effects of ionizing radiation, Volume 1; Vienna, Austria; March 13-17, 1978:387-412.
HAN78c. Reissland JA. An assessment of the Mancuso study. National Radiological Protection Board document NRPB R79; September 1978.
HAN78d. Sanders BS. Low-level radiation and cancer deaths. Health Physics 1978; 34:521-538.
HAN79a. Gilbert ES, Marks S. An Analysis of the Mortality of Workers in a Nuclear Facility. Radiation Research 1979; 79:122-148.
HAN79b. Gofman J. Question of radiation causation of cancer in Hanford workers. Health Physics 1979; 37:617-639.
HAN79c. Hutchison GB, Jablon S, Land CE, MacMahon B. Review of report by Mancuso, Stewart, and Kneale of radiation exposure of Hanford workers, draft report. Health Physics 1979; 37:207-220.
HAN80a. Gilbert ES, Marks S. An Updated Analysis of Mortality of Workers in a Nuclear Facility. Radiation Research 1980; 83:740-741.
HAN80b. Stewart A, Kneale G, Mancuso T. The Hanford data - A reply to recent criticisms. Ambio 1980; 9:67-73.
HAN81a. Darby SC, Reissland JA. Hanford radiation study. British Journal of Industrial Medicine 1981; 38:202-203.
HAN81b. Kneale GW, Mancuso TF, Stewart AM. Hanford radiation study III: a cohort study of the cancer risks from radiation to workers at Hanford (1944-77 deaths) by the method of regression models in life tables. British Journal of Industrial Medicine 1981; 38:156-166.
HAN82. Mole RH. Hanford radiation study. British Journal of Industrial Medicine 1982;39:200-202.
HAN83a. Baverstock KF. Hanford radiation study. British Journal of Industrial Medicine 1983;40:115.
HAN83b. Milham S. Occupational mortality in Washington state, 1950-1979. National Institute for Occupational Safety and Health; DHHS (NIOSH) Publication No. 83-116. (Microfiche tables describing Atomic Workers).
HAN83c. Savitz DA. A critical review of the Hanford worker studies: Cancer risk and low-level radiation. In: Proceedings of the 16th Mid-Year Topical Meeting: Epidemiology Applied to Health Physics, CONF-830101, pp 495-503, January 9-13, 1983, Albuquerque, New Mexico.
HAN83d. Tolley HD, Marks S, Buchanan JA, Gilbert ES. A Further update of the Analysis of mortality of workers in a nuclear facility. Radiation Research 1983; 95:211-213.
HAN84. Kneale GW, Mancuso TF, Stewart AM. Job related mortality risks of Hanford workers and their relation to cancer effects of measured doses of external radiation. British Journal of Industrial Medicine 1984; 41:9-14.
HAN85a. Gilbert ES, Petersen GR. A note on job related mortality risks of Hanford workers and their relation to cancer effects of measured doses of external radiation. British Journal of Industrial Medicine 1985; 42:137-139.
HAN85b. Stewart AM, Kneale GW. Job related mortality risks of Hanford workers and their relation to cancer effects of measured doses of external radiation. British Journal of Industrial Medicine 1985;42:568-569.
HAN88a. Gilbert ES. The Hanford study: Issues in analysing and interpreting data from occupational studies. In: Health effects of low dose ionising radiation - Recent advances and their implications. London: Thomas Telford, 1988:81-85.
HAN88b. Sever LE, Gilbert ES, Hessol NA, McIntyre JM. A case-control study of congenital malformations and occupational exposure to low-level ionizing radiation. American Journal of Epidemiology 1988; 127:226-242.
HAN89. Gilbert ES, Petersen GR, Buchanan JA. Mortality of workers at the Hanford site:1945-1981. Health Physics 1989; 56:11-25.
HAN90a. Cate S, Ruttenber AJ, Conklin AW. Feasibility of an epidemiologic study of thyroid neoplasia in persons exposed to radionuclides from the Hanford nuclear facility between 1944 and 1956. Health Physics 1990; 59:169-178.
HAN90b. Petersen GR, Gilbert ES, Stevens RG, Buchanan JA. A case-cohort study of lung cancer, ionizing radiation, tobacco smoking and occupation among males at the Hanford Site. Health Physics 1990; 58:3-11.
HAN91a. Kneale GW, Sorahan T, Stewart AM. Evidence of biased recording of radiation doses of Hanford workers. American Journal of Industrial Medicine 1991; 20:799-803.
HAN91b. Sever LE. Parental radiation exposure and children's health: Are there effects on the second generation? Occupational Medicine: State of the Art Reviews 1991; 6:613-627.
HAN92. Fix JJ, Gilbert ES, Wilson RH, Baumgartner WV, Nichols LL. Comments on "Evidence of biased recording of radiation doses of Hanford workers." American Journal of Industrial Medicine 1992; 22:281-283.
HAN93a. Gilbert ES, Omohundro E, Buchanan JA, Holter, NA. Mortality of workers at the Hanford Site: 1945-1986. Health Physics 1993; 64:577-590.
HAN93b. Kneale GW, Stewart AM. Reanalysis of Hanford Data: 1944-1986 deaths. American Journal of Industrial Medicine 1993; 23:371-389.
HAN93c. Stewart AM, Kneale GW. The Hanford Data: Issues of age at exposure and dose recording. The PSR Quarterly 1993; 3:101-111.
HAN93d. Vaughan TL, Lee JAH, Strader CH. Breast cancer incidence at a nuclear facility: Demonstration of a morbidity surveillance system. Health Physics 1993; 64:349-354.
HAN95. Gilbert ES, Fix JJ. Accounting for bias in dose estimates in analyses of data from nuclear worker mortality studies. Health Physics 1995;68:650-660.
HAN96. Stewart AM, Kneale GW. Relations between age at occupational exposure to ionizing radiation and cancer risk. Occupational and Environmental Medicine 1996; 53:225-230.
HAN97. Stewart A. Risk estimation for badge-monitored radiation workers. Environmental Health Perspectives 1997; 105 Supplement 6:1603-1606.
HAN99. Fred Hutchnison Cancer Research Center. Hanford Thyroid Disease Study Draft Final Report, January 28,1999. Internet Address: http://www.fhcrc.org/science/phs/htds/.
LANL73. Hempelmann LH, Langham WH, Richmond CR, Voelz GL. Manhattan Project plutonium workers: A twenty-seven year follow-up study of selected cases. Health Physics 1973; 25:461-479.
LANL78. Voelz GL, Stebbings JH, Hempelmann LH, Haxton LK, York DA. Studies on persons exposed to plutonium. In: Late biological effects of ionizing radiation, Volume 1, 1978 (IAEA-SM-224). Vienna: International Atomic Energy Agency.
LANL82. Acquavella JF, Tietjen GL, Wilkinson GS, Key CR, Voelz GL. Malignant melanoma incidence at the Los Alamos National Laboratory. Lancet 1982; 1:883-4.
LANL83a. Acquavella JF, Wilkinson GS, Tietjen GL, Key CR, Stebbings JH, Voelz GL. A melanoma case-control study at the Los Alamos National Laboratory. Health Physics 1983; 45:587-592.
LANL83b. Acquavella JF, Wilkinson GS, Tietjen GL, Key CR, Stebbings JH, Voelz GL. A melanoma case-control study at the Los Alamos National Laboratory. Health Physics 1983; 45:587-592.
LANL83c. Acquavella JF, Wilkinson GS, Wiggs, LD, Tietjen GL, Key CR. An evaluation of cancer incidence among employees at the Los Alamos National Laboratory. In: Proceedings of the 16th Mid-Year Topical Meeting: Epidemiology Applied to Health Physics, CONF-830101, pp 338-345 January 9-13, 1983, Albuquerque, New Mexico.
LANL83d. Voelz GL, Wilkinson GS, Acquavella JF, Tietjen GL, Brackbill RN, ReyesM; Wiggs LD. An update of epidemiologic studies of plutonium workers. Health Physics 1983; 44(Suppl 1):493-503.
LANL83e. Voelz GL, Wilkinson GS, Acquavella JF, Tietjen GL, Brackbill RN, Reyes M, Wiggs LD. An update of epidemiologic studies of plutonium workers. Health Physics 1983; 44(Suppl 1):493-503.
LANL85a. Voelz GL, Grier RS. A 37-year medical follow-up of Manhattan Project Pu workers. Health Physics 1985; 48:249-259.
LANL85b. Voelz GL, Wilkinson GS, Healy JW, McInroy JF, Tietjen GL. Mortality study of Los Alamos workers with higher exposures to plutonium. Los Alamos National Laboratory paper LA-UR-83-85.
LANL91. Voelz GL, Lawrence JNP. A 42-y medical follow-up of Manhattan Project plutonium workers. Health Physics 1991; 61:181-190.
LANL92. Galke WA, Johnson ER, Tietjen GL. Mortality in an ethnically diverse radiation exposed occupational cohort. Los Alamos National Laboratory (Occupational Medicine Group), November 24, 1992. Draft technical report.
LANL94. Wiggs LD, Johnson ER, Cox-DeVore CA, Voelz GL. Mortality through 1990 among white male workers at the Los Alamos National Laboratory: considering exposures to plutonium and external ionizing radiation. Health Physics 1994; 67:577-588.
LANL97. Voelz GL, Lawrence JNP, Johnson ER. Fifty years of plutonium exposure to the Manhattan Project plutonium workers: An update. Health Physics 1997; 73:611-619.
LIND87. Dupree EA, Cragle DL, McLain RW, Crawford-Brown DJ, Teta MJ. Mortality among workers at a uranium processing facility, the Linde Air Products Company Ceramics Plant, 1943-1949. Scandinavian Journal of Work, Environment, and Health 1987; 13:100-107.
LLNL81. Austin DF, Snyder MA, Reynolds PJ, Biggs MW, Stubbs HA. Malignant melanoma among employees of Lawrence Livermore National Laboratory. Lancet 1981; 2:712-716.
LLNL85a. Reynolds P, Austin DF. Cancer incidence among employees of the Lawrence Livermore National Laboratory, 1969-1980. Western Journal of Medicine 1985; 142:214-218.
LLNL85b. Shy CM, Checkoway H, Marshall EG. Malignant melanoma at a scientific laboratory. A synthesis of reviewer's comments on the Austin and Reynold's study of employees at the Lawrence Livermore National Laboratory. Lawrence Livermore National Laboratory Report No.: UCRL-15737 (S/C 7532605) 15 Nov 1985, 57 pp. Contract Number W-7405-ENG-48.
LLNL86. Austin DF, Reynolds PJ. Occupation and malignant melanoma of the skin. In: Recent Results in Cancer Research 1986; 102:98-107. Berlin:Springer-Verlag.
LLNL90a. Schwartzbaum JA, Setzer RW, Kupper LL. An exploratory analysis of the occupational correlates of large pigmented nevi at Lawrence Livermore National Laboratory. Journal of Occupational Medicine 1990; 32:605-611.
LLNL90b. Schneider JS, Moore DH, Sagebiel RW. Early diagnosis of cutaneous malignant melanoma at Lawrence Livermore National Laboratory. Archives of Dermatology 1990; 126:767-769.
LLNL93. Hiatt RA, Krieger N, Sagebiel RW, Clark WH Jr, Mihm MC Jr. Surveillance bias and the excess risk of malignant melanoma among employees of the Lawrence Livermore National Laboratory. Epidemiology 1993; 4:43-47.
LLNL97a. Austin DF, Reynolds PJ. Investigation of an excess of melanoma among employees of the Lawrence Livermore National Laboratory. American Journal of Epidemiology 1997; 145:524-531.
LLNL97b. Moore DH, Patterson HW, Hatch F, Discher D, Schneider JS, Bennett D, Mendelsohn ML. Case-control study of malignant melanoma among employees of the Lawrence Livermore National Laboratory. American Journal of Industrial Medicine 1997; 32:377-391.
MCW98. Dupree Ellis E, Watkins JP, Ingle JA, Phillips JA. External radiation exposure and mortality among a cohort of uranium processing workers. Center for Epidemiologic Research, Oak Ridge Institute for Science and Education, Oak Ridge, Tennessee. Final Report to the National Institute for Occupational Safety and Health under contract number 200-93-2695, September 1998.
MND91a. Wiggs LD, Cox-DeVore CA, Voelz GL. Mortality among a cohort of workers monitored for 210Po exposure:1944-1972. Health Physics 1991;61:71-76.
MND91b. Wiggs LD, Cox-DeVore CA, Wilkinson GS, Reyes M. Mortality among workers exposed to external ionizing radiation at a nuclear facility in Ohio. Journal of Occupational Medicine 1991; 33:632-637.
MULTI83. Mortality patterns among a retrospective cohort of uranium mill workers. Waxweiler RJ, Archer VE, Roscoe RJ, Watanabe A, Thun MJ. In: Proceedings of the 16th Mid-Year Topical Meeting: Epidemiology Applied to Health Physics, CONF-830101, pp 427-435, January 9-13, 1983, Albuquerque, New Mexico.
MULTI89. Gilbert ES, Fry SA, Wiggs LD, Voelz GL, Cragle DL, Petersen GR. Analysis of combined mortality data on workers at the Hanford Site, Oak Ridge National Laboratory, and Rocky Flats nuclear weapons plant. Radiation Research 1989; 120:19-35.
MULTI90. Gilbert ES, Fry SA, Wiggs LD, Voelz GL, Cragle DL, Petersen GR. Methods for analyzing combined data from studies of workers exposed to low doses of radiation. American Journal of Epidemiology 1990;131:917-927.
MULTI90. Jablon S, Hrubec Z, Boice JD, Stone BJ. Cancer in Populations Living Near Nuclear Facilities. Volume 1. Report and Summary. U.S. Department of Health and Human Services, National Cancer Institute. (NIH Publication No. 90-874:56-70).
MULTI93. Gilbert ES, Cragle DL, Wiggs LD. Updated analyses of combined mortality data for workers at the Hanford Site, Oak Ridge National Laboratory, and Rocky Flats Weapons Plant. Radiation Research 1993; 136:401-421.
MULTI94. IARC Study Group on Cancer Risk among Nuclear Industry Workers. Direct estimates of cancer mortality due to low doses of ionising radiation: An international study. Lancet 1994; 344:1039-1043.
MULTI95a. Cardis E, Gilbert ES, Carpenter L, Howe G, Kato I, Armstrong BK, Beral V, Cowper G, Douglas A, Fix J, et al. Effects of low doses and low dose rates of external ionizing radiation: Cancer mortality among nuclear industry workers in three countries. Radiation Research 1995; 142:117-132.
MULTI95b. Dupree EA, Watkins JP, Ingle JN, Wallace PW, West CM, Tankersley WG. Uranium dust exposure and lung cancer risk in four uranium processing operations. Epidemiology 1995; 6:370-375.
MULTI96. Fry SA, Dupree EA, Sipe AH, Seiler DL, Wallace PW. A study of mortality and morbidity among persons occupationally exposed to >=50 mSv in a year: Phase I, mortality through 1984. Journal of Applied Occupational and Environmental Hygiene 1996; 11:334-343.
MULTI98a. Sever LE. Epidemiologic evaluation of childhood leukemia and paternal exposure to ionizing radiation. Batelle Pacific Northwest Laboratories. Final Report to the National Institute for Occupational Safety and Health under cooperative agreement number U50/CCU 008 710, September 1998.
MULTI98b. Wing S. Case control study of multiple myeloma among workers exposed to ionizing radiation and other physical and chemical agents. The University of North Carolina. Final Technical Report to the National Institute for Occupational Safety and Health under contract number 200-93-2628, January 15, 1998.
ORC81. Polednak AP. Mortality among welders, including a group exposed to nickel oxides. Archives of Environmental Health 1981; 36:235-241.
ORC87a. Carpenter AV, Flanders WD, Frome EL, Cole P, Fry SA. Brain cancer and nonoccupational risk factors: a case-control study among workers at two nuclear facilities. American Journal of Public Health 1987; 77:1180-1182.
ORC87b. Carpenter AV, Flanders WD, Frome EL, Crawford-Brown DJ, Fry SA. CNS cancers and radiation exposure: a case-control study among workers at two nuclear facilities. Journal of Occupational Medicine 1987;29:601-604.
ORC88. Carpenter AV, Flanders WD, Frome EL, Tankersley WG, Fry SA. Chemical exposures and central nervous system cancers: a case-control study among workers at two nuclear facilities. American Journal of Industrial Medicine 1988; 13:351-362.
ORC90. Frome EL, Cragle DL, NcLain RW. Poisson regression analysis of the mortality among a cohort of WWII nuclear Industry Workers. Radiation Research 1990; 123:138-152.
ORC97a. Frome EL, Cragle DL, Watkins JP, Wing S, Shy CM, Tankersley WG, West CM. A mortality study of employees of the nuclear industry in Oak Ridge, Tennessee. Radiation Research 1997; 148:64-80. [Published erratum appears in Radiat Res 1997; 148:297-298.]
ORC97b. Frome EL, Cragle DL, Watkins JP, Wing S, Shy CM, Tankersley WG, West CM. A mortality study of employees of the nuclear industry in Oak Ridge, Tennessee. Final Report to the U.S. Department of Energy under contract number DE-AC05-96OR22464. Oak Ridge National Laboratory, Oak Ridge, Tennessee. Report number ORNL-6785, July 1997.
ORC97c. Watkins JP, Cragle DL, Frome EL, Reagan JL, West CM, Crawford-Brown D, Tankersley WG. Collection, validation, and treatment of data for mortality study of nuclear industry workers. Applied Occupational and Environmental Hygiene 1997; 12:195-205.
ORC98. Wells S, Cragle DL, Tankersley WG. Mortality update among welders at multiple sites. Final Report. Oak Ridge Associated Universities Document 98-0790. National Technical Information Service.
ORK79. Godbold JH Jr and Tompkins EA. A long-term mortality study of workers occupationally exposed to metallic nickel at the Oak Ridge Gaseous Diffusion Plant. Journal of Occupational Medicine 1979; 21:799-806.
ORK84. Cragle DL, Hollis DR, Newport TH, Shy CM. A retrospective cohort mortality study among workers occupationally exposed to metallic nickel powder at the Oak Ridge Gaseous Diffusion Plant. In: Nickel in the Human Environment, IARC Scientific Publications No. 53, 1984; Lyon, International Agency for Research on Cancer:57-63.
ORK92. Cragle DL, Wells SM, Tankersley WG. An occupational morbidity study of a population potentially exposed to epoxy resins, hardners and solvents. Applied Occupational and Environmental Hygiene 1992; 7:826-834.
ORK96. Dupree EA, Wells SM, Watkins JP, Wallace PW, Davis NC. Mortality among workers employed between 1945 and 1984 at a uranium gaseous diffusion facility. Center for Epidemiologic Research, Oak Ridge Institute for Science and Education, Oak Ridge, Tennessee. Final Report to the National Institute for Occupational Safety and Health under contract number DE-AC05-76ORO00033, February 1996.
ORX85. Checkoway H, Mathew RM, Shy CM, Watson JE Jr, Tankersley WG, Wolf SH, Smith C, Fry SA. Radiation, work experience, and cause specific mortality among workers at an energy research laboratory. British Journal of Industrial Medicine 1985;42(8):525-33.
ORX91. Wing S, Shy CM, Wood JL, Wolf S, Cragle DL, Frome EL. Mortality among workers at Oak Ridge National Laboratory. Evidence of radiation effects in follow-up through 1984. Journal of the American Medical Association 1991; 265:1397-1402. [Published errata appear in JAMA 1991; 266:657.]
ORX93. Wing S, Shy CM, Wood JL, Wolf S, Cragle DL, Tankersley W, Frome EL. Job factors, radiation and cancer mortality at Oak Ridge National Laboratory: follow-up through 1984. American Journal of Industrial Medicine 1993; 23:265-279. Published errata appear in American Journal of Industrial Medicine 1993; 23:673.
ORX94. Shy CM, Wing S. Comprehensive epidemiology of DOE atomic workers. A report on mortality among workers at Oak Ridge National Laboratory: Follow-up through 1990. University of North Carolina. Final Report to the National Institute for Occupational Safety and Health under Purchase Order number 3C-70837, March 31, 1994.
ORX97. Wing SB, Richardson, DB. Time-related factors in radiation-cancer dose response. University of North Carolina. Final Report to the National Institute for Occupational Safety and Health under grant number R03 OH03343, August 5, 1997.
ORX98. Richardson DB, Wing S. Methods for investigating age differences in the effects of prolonged exposures. American Journal of Industrial Medicine 1998; 33:123-130.
ORX99. Richardson DB, Wing S. Radiation and mortality of workers at Oak Ridge National Laboratory: Positive associations for doses received at older ages. Environmental Health Perspectives 1999; 107:649-656.
ORY80. Polednak AP. Mortality among men occupationally exposed to phosgene in 1943-1945. Environmental Research 1980; 22:357-367.
ORY81. Polednak AP, Frome EL. Mortality among men employed between 1943 and 1947 at a uranium-processing plant. Journal of Occupational Medicine 1981; 23:169-178.
ORY83. Cookfair DL, Beck WL, Shy C, Lushbaugh CC, Sowder CL. Lung cancer among workers at a uranium processing plant. In: Proceedings of the 16th Mid-Year Topical Meeting: Epidemiology Applied to Health Physics, CONF-830101, pp 398-406, January 9-13, 1983, Albuquerque, New Mexico.
ORY84. Cragle DL, Hollis DR, Qualters JR, Tankersley WG, Fry SA. A mortality study of men exposed to elemental mercury. Journal of Occupational Medicine 1984; 26:817-821.
ORY85. Polednak AP and Hollis DR. Mortality and causes of death among workers exposed to phosgene in 1943-45. Toxicology and Industrial Health 1985; 1:137-151
ORY88a. Albers JW, Kallenbach LR, Fine LJ, Langolf GD, Wolfe RA, Donofrio PD, Alessi AG, Stolp-Smith KA, Bromberg MB. Neurological abnormalities associated with remote occupational elemental mercury exposure. Annals of Neurology 1988; 24:651-659.
ORY88b. Checkoway H, Pearce N, Crawford-Brown DJ, Cragle DL. Radiation doses and cause: specific mortality among workers at a nuclear materials fabrication plant. American Journal of Epidemiology 1988; 127:255-366. Comment in: American Journal of Epidemiology 1989; 129:639-640.
ORY96. Loomis DP, Wolf SH. Mortality of workers at a nuclear materials production plant at Oak Ridge, Tennessee, 1947-1990. American Journal of Industrial Medicine 1996; 29:131-141. Comment in: American Journal of Industrial Medicine 1997; 31:121.
ORY97. Cragle D, Letz R. A study of the health effects of exposure to elemental mercury: A follow-up of mercury exposed workers at the Y-12 Plant in Oak Ridge, Tennessee. Final Report: NIOSH Contract No. 200-93-2629, 1997. Oak Ridge Associated Universities and Emory University.
PTS87. Brown DP, Bloom T. Mortality among uranium enrichment workers. National Institute for Occupational Safety and Health, January 1987. Report No. PB87-188991.
PTX85. Acquavella JF, Wiggs LD, Waxweiler RJ, Macdonell DG, Tietjen GL, Wilkinson GS. Mortality among workers at the Pantex weapons facilityHealth Physics 1985; 48:735-746.
RAI97. Morgenstern H, Froines J, Ritz B, Young B. Epidemiologic study to determine possible adverse effects to Rocketdyne/Atomics International workers from Exposures to Ionizing Radiation. University of California at Los Angeles. Final Report to the California Public Health Institute under subcontract number 324A-8701-S0163, June 1997.
RAI99a. Ritz B, Morgenstern H, Froines J, Batts Young B. Effects of exposure to external ionizing radiation on cancer mortality in nuclear workers monitored for radiation at Rocketdyne/Atomics International. American Journal of Industrial Medicine 1999; 35:21-31.
RAI99b. Ritz B, Morgenstern H, Moncau J. Age at exposure modifies the effects of low-level ionizing radiation on cancer mortality in an occupational cohort. Epidemiology 1999; 10:135-140.
RFP83a. Voelz GL, Wilkinson GS, Acquavella JF, Tietjen GL, Brackbill RN, Reyes M, Wiggs LD. An update of epidemiologic studies of plutonium workers. Health Physics 1983; 44(Suppl 1):493-503.
RFP83b. Wilkinson GS, Voelz GL, Acquavella JF, Tietjen GL, Brackbill RN, Reyes M, Wiggs LD. Mortality among plutonium and other workers at a nuclear facility. . In: Proceedings of the 16th Mid-Year Topical Meeting: Epidemiology Applied to Health Physics, CONF-830101, pp 328-337, January 9-13, 1983, Albuquerque, New Mexico.
RFP84. Reyes M, Wilkinson GL, Tietjen G. Brain tumors at a nuclear facility. Journal of Occupational Medicine 1984; 26:721-724.
RFP87. Wilkinson GS, Tietjen GL, Wiggs LD, Galke WA, Acquavella JF, Reyes M, Voelz GL, Waxweiler RJ. Mortality among plutonium and other radiation workers at a plutonium weapons facility. American Journal of Epidemiology 1987; 125:231-250.
SRS88. Cragle DL, McLain RW, Qualters JR, Hickey JLS, Wilkinson GS, Tankersley WG, Lushbaugh CC. Mortality among workers at a nuclear fuels production facility. American Journal of Industrial Medicine 1988; 14:379-401.
SRS94. Cragle DL, Robertson-DeMers K, Watkins JP. Mortality among workers at a nuclear fuels production facility: The Savannah River Site, 1952-1986. Center for Epidemiologic Research, Oak Ridge Institute for Science and Education, Oak Ridge, Tennessee. Final Report to the National Institute for Occupational Safety and Health under DOE contract DE-AC05-76ORO00033, 1994.
USUR98. Gold B, Kathren RL. Causes of death in a cohort of 260 plutonium workers. Health Physics 1998; 75:236-240.
VELA98. Richter BS, Stockwell HS. Descriptive study of deaths from cancer associated with residential proximity to the site of underground nuclear detonations. Archives of Environmental Health 1998; 53:109-113.
ZZZ79. Rundo J, Polednak AP, Brues AM, Lucas HF Jr, Patten BC, Rowland RE, Stehney AF. Study of radioactivity and health status of former thorium workers. Environmental Research 1979; 18:94-100.
ZZZ83. Polednak AP, Stehney AF, Lucas HF. Mortality among male workers at a thorium-processing plant. Health Physics 1983; 44 (Suppl 1):1239-1251.
________________
APPENDIX 3
Table 4. FREQUENTLY CITED DOE CHEMICAL CONTAMINANTS
CHEMICALSTATUSMETALSARSENIC1BERYLLIUM2CADMIUM1CHROMIUM1COPPER1LEAD1MERCURY1NICKEL (WELDING)2ZINC1RADIONUCLIDESCESIUM1IODINE2PLUTONIUM1POLONIUM2STRONTIUM1TRITIUM1URANIUM1GASES/PARTICLESASBESTOS1DIESEL EMISSIONS2FIBERGLASS2FREON2METAL MACHINING FLUIDS2PHOSGENE2RADON2SILICA2CHLORINATED HYDROCARBONSTCE11,1,1-TRICHLOROETHANE11,2-DICHLOROETHYLENE1TETRACHLOROETHYLENE11,1-DICHLOROETHANE1CHLOROFORM1DICHLOROMETHANE1PCBs2METHYLENE CHLORIDE2FUEL HYDROCARBONSBENZENE1ETHYLBENZENE1TOLUENE1XYLENES1KETONESACETONE1METYL ETHYL KETONE1PHTHALATESBIS-2 ETHYLEXYLPHTHALATE1OTHER HAZARDSEPOXY RESINS2FLUORINE COMPOUNDS2FORMALDEHYDE2HEAT2HYDRAZINE2MIXED CHEMICALS2NOISE2ACIDS2VOLATILE ORGANIC COMPOUNDS2
1 = Known groundwater or soil contaminant 2 = Known building or workplace hazard.
Reference: Chemical Contaminants on DOE Lands and Selection of Contaminants Mixtures for Subsurface
Science Research. DOE/ER-0547T. April 1992.
Figure 2. Production and Testing Pathway for US Nuclear Weapons
Table 5. DOE Facilities and Sites by Role in the Nuclear Weapons Complex
U refining and metallurgyU enrichment & isotope separation U Fuel rods & targetsProduction reactorsChemical separationsNuclear componentsNon nuclear componentsWeapons assembly & modification Research & DevelopmentTestingReference most recent morbidity/mortality studyAmchitka Island Test Site (AK)· -Argonne National Laboratory*· -Atlantic & Southern Pacific Test Sites· -Fernald Feed Materials Production Center (OH)· · FMPC96Hanford Site (WA) · · · · · HAN93aINEEL (ID)· · -Kansas City Plant (MO)· -Lawrence Berkeley National Laboratory (CA)· -Lawrence Livermore National Laboratory (CA)· LLNL85aLinde Air Products (NY)· LIND87Los Alamos National Laboratory (NM)· · LANL94Mallinckrodt Chemical Works (MO)· MCW98Mound Facility (OH)· · MND91aNevada Test Site· -Oak Ridge K-25 GDP (TN)· ORK96Oak Ridge X-10 (TN)· ORX91Oak Ridge Y-12 (TN)· · · · ORY97bPaducah GDP (KY)· -Pantex Plant (TX)· · PTX85Pinellas Plant (FL)· · -Portsmouth GDP (OH)· PTS87Project Plowshare Test Sites (NV,NM,CO)· -Rocky Flats Plant (CO)· RFP83Sandia National Laboratory (NM)· -Savannah River Site (SC)· ·· · · SRS94Tatum Dome/Vela Uniform Test Sites (AK,MS,NV)· VELA98Weldon Springs (MO)· -
*Italics indicates that no mortality study has been initiated. The Idaho National Engineering and Environmental Laboratory in currently under study. Naval Nuclear facilities, by executive order, are a separate and independent program.
APPENDIX 4
SUMMARY OF FINDINGS FROM SPECIAL RADIATION STUDIES
Los Alamos Plutonium Workers:
· Twenty-six white male workers, who did the original plutonium research and development work at the Los Alamos National Laboratory before 1946 and received large internal deposition, volunteered for this medical monitoring program.
· They have been medically evaluated every five years for possible health effects.
· The average dose each worker received over the 50-year period since 1945 was 1,250 mSv (125 rem).
· The initial exposures were large- some 5 to 360 times the current annual limit on intake.
Results:
· To date there have been 7 worker deaths in this group.
· Three have died from cancers (lung, prostate, osteosarcoma).
· The one bone cancer (osteosarcoma) which a rare condition is of interest since plutonium is known to deposit in the bone.
Reference: George L. Voelz, James N. P. Lawrence, and Emily R. Johnson. 1997. Fifty Years of Plutonium Exposure to the Manhattan Project Plutonium Workers: an Update. Health Physics 73(4):611-619.
Rocky Flats High RAD Workers Program:
In July 1992, a program was initiated that replaced a Rocky Flats Site Clinic program aimed at former employees with internal depositions of radionuclides. The surveillance program is aimed at any former worker with more than 200 mSv (20 rem) lifetime total effective dose equivalent (TEDE) exposure to both internal and external radiation. In addition to providing periodic medical surveillance, the program collects health histories of high dose workers and develops doses models of internal depositions.
To date 860 individuals have been examined. More than 400 are eligible to continue participation based on lifetime TEDEs greater than 200 mSv. A sentinel case of lung fibrosis among plutonium-exposed worker has been diagnosed. Of 251 former worker records that have been analyzed, 4.9% show chest X-ray changes consistent with asbestos exposure. A complete analysis of other health outcomes is pending.
US Transuranium and Uranium Registries:
Background
The United States Transuranium and Uranium Registries (USTUR) are a unique DOE-sponsored research program that studies how plutonium, uranium and other heavy radioactive metals (called actinides) distribute themselves within the human body and what biological effects those metals have on body organs. Organ samples are acquired post-mortem from volunteer donors who worked with the radioactive metals and who, at some time during their work history, had an established intake of those metals into their bodies.
· During the past 30 years, the USTUR has received autopsy samples from about 360 donors. Of these, 24 have been whole body donations, providing a unique opportunity for thorough investigation of the distribution of actinides in the human body. The analyses of bones of entire skeletons from whole body donations, has enabled the USTUR to determine the radiation dose to bone and its relationship to radiation-induced bone tumors, which are one of the prime concerns of radiation protection regulations governing intakes of the actinide elements.
· Approximately 5,000 organ samples have been collected and analyzed for isotopes of uranium, plutonium, thorium, and americium resulting in more than 15,000 analytical results for various organs of the body. These measurements have formed the basis for a large number of scientific reports, and 133 of those reports have been published in the peer-reviewed, scientific literature.
· The program continues to add to this unique set of data through the continued donation of tissues from exposed workers with confirmed intakes. At present, there are about 230 living workers or former workers who are registered in the program.
Results:
A number of observations regarding the health effects of plutonium, americium, and other elements in the body are possible based on USTUR data. Among them:
Based on USTUR data, donors suffered no health effects from plutonium. Table 5 contains the results of a recent study of the causes of death of USTUR organ donors. Most of them died from the same diseases occurring in the US population, heart disease, strokes, and cancers not necessarily associated with radiation exposure. The average age at death of USTUR registrants is 63 years (range between 25 and 91 years). The average age of USTUR registrants who are still living is 73 years (range between 30 and 93 years).
There were 28 cases of lung cancer among USTUR. There were also six cases of mesothelioma, a type of cancer associated with asbestos exposure, and a records search indicated asbestos handling in the work histories of all six cases.
There was a cluster of seven brain cancers at Rocky Flats. An examination of radiation exposure records of the seven cases gave no indication of a radiological cause of those tumors. Although the work site was a plutonium processing facility, three of the workers had very low body burdens of plutonium at death (less than 1% of the regulatory limit, which was 40 nanocuries in the total body) and none of the remaining four had depositions close to that amount.
Of the 244 registrants for whom cause of death is known, there were only two cases in which diseases found at death may be considered to be a result of their intakes of plutonium or americium. One of those men was a Hanford worker who received a very high exposure to americium from a chemical explosion of material that he was handling. Initial estimates were that he had 4 - 5 times the regulatory limit in his lungs, liver, and skeleton with four times that embedded in the skin of his face. This person had decreased numbers of certain blood cells that began after the incident and continued until his death eleven years later from heart disease. This was not unexpected in that he had had a heart attack a few years before the exposure incident. Another worker, who had been exposed to plutonium, died from bone cancer (osteosarcoma). Bone cancer is rare in someone of his age (66 years at death) and it is one of the tumors associated with intakes of plutonium in experiments with animals. Based on biokinetic models and bioassays taken shortly before his death, his plutonium body burden was estimated to be 15 nanocuries (550 Becquerels). Radiochemical analyses of tissues after autopsy indicated a burden of 6.8 nanocuries (250 Becquerels), about the same level as the body burdens of other USTUR donors who did not have bone tumors.
The vast majority of USTUR organ sample donors had body burdens that were less than 5% of the regulatory limit at the time that they worked with plutonium and, based on the USTUR data, they suffered no health effects from plutonium. However, this appears not be the case with Russian workers who have much larger plutonium exposures: on average, the Russian workers had approximately 250 times as much plutonium in their bodies as did the workers in the USTUR. While the studies of Russian workers are not yet complete, it appears that they did have larger than usual numbers of lung cancers, liver cancers, and bone cancers. The average plutonium body burden of the Russian workers was approximately 60 nanocuries or about 1.5 times the U. S. regulatory limit.
Table 6. Causes of death among 244 workers who donated organ samples to the USTUR
Cause of Death Number Cause of Death Number
Diseases of blood Esophageal cancer 2
forming organs 1 Stomach cancer 4
Neurological diseases 7 Colon cancer 4
Arteriosclerotic heart Rectal cancer 3
disease 80 Liver cancer 4
Other circulatory disease 2 Pancreatic cancer 3
Pulmonary embolism 4 Laryngeal cancer 2
Myocarditis 1 Lung cancer 28
Cardiomyopathy 9 Mesothelioma 6
Diffuse arteriosclerosis 1 Bone cancer 1
Cerebrovascular accidents 8 Melanoma 4
Vascular diseases 3 Prostate cancer 7
Pneumonia 5 Bladder cancer 2
Chronic obstructive Kidney cancer 4
pulmonary disease 10 Brain cancer 7
Intestinal diseases 1 Lymphoma 2
Liver diseases 4 Multiple myeloma 1
Aspiration 1 Leukemia 3
Sepsis 2
Accidents (auto) 7
Suicides 7
Reference: Health Physics 75:236-240, 1998
Table 7
APPENDIX 5
SUMMARY OF FINDINGS FROM OTHER SURVEILLANCE PROGRAMS
1) The Epidemiologic Surveillance Program
Background
About 65,000 workers are covered under this program. Data from the most recent year where complete information is available, 1997, are presented. The SHEO's are identified from return-to-work clearances that indicate illness and injury diagnoses among workers who have been absent five or more consecutive workdays.
A sentinel health event for occupations (SHEOs) is a "disease, disability, or death which is occupationally related and whose occurrence may serve as a warning signal that materials substitution, engineering controls, personal protection, or medical care may be required." Sixty-four medical conditions associated with workplace exposures from studies of many different industries were identified as sentinel health events. Although SHEOs may indicate an occupational exposure, many may result from non-occupational exposures. Due to this uncertainty, SHEOs are assessed in two categories: 1) definite sentinel health events - diseases that are unlikely to occur in the absence of an occupational exposure, and 2) possible sentinel health events - conditions that may or may not be related to occupation.
Results:
There were 516 SHEO's (definite and possible) identified among workers at 8 DOE sites participating in the Epidemiologic Surveillance program in 1997..
Injuries (n= 311) account for the majority, 60.3% of the SHEOs, followed by 80 (15.5%) muscle and skeletal disorders, and 73 (14.1%) diagnoses related to the nervous system. Thirteen (2.5%) cancers and 7 (1.4%) respiratory diagnoses were identified as SHEOs. The breakdown by ICD code for the latter three categories is provided in Table 8. As shown in Table 8, the cancers were either lung cancers or those of the genitourinary tract (uterine, bladder, ovarian).
Table 8
Breakout of Selected Sentinel Health Events for Occupations (SHEO)
Among DOE Sites Participating in Epidemiologic Surveillance, 1997
NERVOUS SYSTEM n =73
ICD Code Frequency Description
354.1.1 68 carpal tunnel syndrome
354.2 1 mononeuritis of upper limb (lesion of ulnar nerve)
366.9 1 unspecified cataract
369.60 1 profound impairment one eye, unspecified
372.40 1 pterygium, unspecified
386.50 1 labyrinthine dysfunction, unspecified
CANCER n = 13
ICD Code Frequency Description
162.9 7 malignant neoplasm of bronchus and lung, unspecified
188.9 3 malignant neoplasm of bladder, part unspecified
189.0 3 malignant neoplasm of kidney, except pelvis
RESPIRATORY n = 2
ICD Code Frequency Description
493.0 1 extrinsic asthma
500 1 coal workers' pneumoconiosis
Reference: Rutstein DD, Mullan RJ, et al. 1984. Sentinel health events (occupational): A basis for physician recognition and public health surveillance. Arch. Envir. Health 39: 159-168.
2) CAIRS
The Computerized Accident/Incident Reporting System (CAIRS) is a database used to collect and analyze DOE and DOE contractor reports of injuries, illnesses, and other accidents that occur during DOE operations. CAIRS data consist of DOE and DOE contractor reports of injuries and illnesses, property damage, and vehicle accident events. The Occupational Safety and Health Administration's guidelines for reportable cases are used to determine the eligibility of injury/illness cases for reporting to CAIRS.
Most injuries have an immediate, specific cause, facilitating the determination of whether they are occupational. Many other health effects may be less clearly associated with occupational exposures or may develop over a substantial period of time. In general, the CAIRS system best captures information on acute illnesses associated with an event that results in lost time. The system tends to underreport illnesses that are not clearly associated with work and/or chronic progressive illnesses that may not result in lost time.
An effort to summarize these less immediate health effects is presented in the table presented below. They are based on CAIRS data reflecting these selection criteria:
All DOE sites included
Conditions other than injuries
Contractor workers (not Federal employees)
Events occurred during calendar year 1998
The CAIRS data base does not include International Classification of Disease (ICD) codes, using instead a health effect classification system containing a number of broad categories of health effects. Where the CAIRS classification scheme uses these broad categories, no more detailed coding of health effects was available for analysis.
Table 9
Non-Injury Occupational Health Effects among Contractor Workers at all DOE Sites, 1998
Non-Injury Occupational Health Effects among Contractor Workers at All DOE Sites, 1998 Health EffectNumber of EventsTotal Lost WorkdaysAverage* Lost Workdays per EventTotal Restricted WorkdaysAverage* Restricted Workdays per EventEffects of Environmental ConditionsHeat stroke, other effects of high temperatures277<17<1Other Poisonings and Toxic EffectsChemical reactions400398100Other poisoning or toxic effects**66141Nervous System and Sensory Organ DiseasesCarpal tunnel syndrome777761091212Conjunctivitis20000Central nervous system disorders1332121Hearing impairment20000Hearing loss70000Other nervous system and sensory organ diseases**759914736Diseases of the Heart or Circulatory SystemOther circulatory system disorders**10000Respiratory System DiseasesAsbestosis10000Berylliosis20000Upper respiratory conditions82<11<1Other respiratory diseases**25422492Digestive System Diseases and DisordersOther digestive system diseases**10022Musculoskeletal System and Connective Tissue Diseases and DisordersBursitis10000Tendonitis957715746Tenosynovitis7183426Other musculoskeletal disorders**134287210998Disorders of the Skin and Subcutaneous TissueAllergic dermatitis40000Contact dermatitis1800845Dermatitis1200182Other skin conditions**363<1521Other Systemic Diseases and DisordersOther systemic diseases and disorders**222911085Infectious and Parasitic DiseasesInfections314500Symptoms, Signs, and Ill-defined ConditionsInflammation1022215215Irritation40000Other symptoms, signs, and ill-defined conditions**6415423245Other Diseases, Conditions, and DisordersMental disorders53136311623Other diseases, conditions, and disorders**240203518Multiple Diseases, Conditions, and DisordersMultiple diseases, conditions, and disorders30041Total6591892344757
*Rounded to the nearest full day
**No finer category breakdown available within CAIRS
________________
APPENDIX 6
SUMMARY OF INITIAL RESULTS FROM THE FORMER WORKER PROGRAM
Background
The Former Workers Program was created at the Department of Energy in response to Public Law 102-484, enacted in 1993. Section 3162 of this law directed DOE to evaluate the long-term health conditions of current and former employees who may be at significant risk of adverse health effects as a result of their employment at DOE sites. To meet these requirements, DOE established the Former Workers Program in October 1996.
The Former Workers Program is divided into two stages: Phase I and Phase II. In 1996, DOE began to support Phase I activities consisting of needs assessments to identify groups of former workers who may benefit from a medical surveillance program. In addition, Phase I was designed to determine if enough information on current and former workers is available to proceed with Phase II. During Phase II, current and former workers are contacted and medical surveillance programs are implemented based on the exposures most likely to produce adverse health effects. The projects are being conducted by cooperative agreements with consortia of universities, unions, and other organizations.
As mandated by the law, the DOE Former Workers Program screens workers who are at high risk. As of November, 1999, DOE supported 10 former workers projects at 9 DOE sites.
Table 10 presents a summary of chest X-ray screening conducted for 709 former workers at three DOE sites. These X-rays are read by individuals ("B-readers") with specialty training in recognition of pneumoconioses. The International Labor Office (ILO) in Geneva, Switzerland, publishes criteria to allow for the standardization of reading chest X-rays. The first number indicates the major category of profusion of abnormal opacities on the film which is based on the concentration or number of small opacities per unit area observed within the lung fields. The second number indicates whether the number of opacities is judged to be less than, equal to, or more than the profusion level expected for the major category.
Categories 0/-, 0/0, and 0/1 are generally regarded as exhibiting no evidence of pneumoconiosis. Chest X-rays in profusion categories 1/0, 1/1, 1/2 or higher are generally regarded as positive for pneumoconiosis.
Of the 882 individuals screened to date, 148 (17%) have category 1/0 or greater perfusion on their chest X-ray.
In addition, 243 workers have been screened at the three DOE gaseous diffusion plants. Of this number, 28 workers (11.5%) were found to have asbestos-related fibrosis. The results of the ILO Perfusion scores were not available at the time of this report.
Data regarding other disease endpoints such as hearing loss were presented to the panel and are being accumulated as part of this program but were felt to be too preliminary for this report.
Table 10
Summary for Respiratory Findings for DOE Former Workers
ILO PerfusionHanford ConstructionHanford ProductionNevada Test Site - TunnelersOak Ridge ConstructionTOTAL00/0 5 [8%] 175 [86%]203 [37%]53 [8%]436 [49%]0/129 [47%] 14 [7%]255 [46%] 0298 [34%]1/012 [21%] 8 [4%] 59 [11%] 4 [6%] 83 [9%}1/1 8 [13%] 4 [2%] 19 [3%] 3 [5%] 34 [4%]1 /2 3 [5%] 2 [1%] 5 [1%] 2 [3%] 12 [1%]2/1 3 [5%] 5 [1%] 0 8 [1%]2/2 0 5 [1%] 0 52/3 1 [2%] 2 [.4%] 0 33/2+ 0 3 [.5%] 0 3Total Number6120355662882
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APPENDIX 7
LIST OF PANEL MEMBERS
Department of Justice
Dianne Spellberg
Gerard Fischer
Environmental Protection Agency
Dr. Ana Maria Osorio
US Navy
CAPT Paul Blake
Department of Defense
CAPT Issac Atkings
CAPT Richard Thomas
Department of Labor
Peter Turcic
Department of Health and Human Services
Roger Rosa
Council of Economic Affairs
Robin Lumsdaine
National Aeronautic and Space Administration
John W. Wilson
Department of Treasury
Robert McNary
Office of Management and Budget
John Pfeiffer
National Economic Council
William Dauster
Department of Energy
Paul Seligman
Heather Stockwell
Contributors to the report from the Department of Energy
Roger Anders, Barbara Brooks, Bonnie Richter, Donald Lentzen, John Peeters, Gerald Petersen, Cliff Strader and Paul Wambach
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