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Workers at the Portsmouth Naval Shipyard (PNS) in Kittery, Maine have been subjects of a number of epidemiologic investigations with different results, particularly for lung cancer and leukemia mortality. The purpose of this nested case-control study was to evaluate the relation between lung cancer risk and external ionizing radiation exposure while adjusting for potential confounders that included gender, radiation monitoring status, smoking habit surrogates (socioeconomic status and birth cohort), welding fumes and asbestos.
Incomplete radiation exposure histories, inadequate treatment of
internally deposited radionuclides, and failure to account for neutron
exposures can be important uncertainties in epidemiologic studies of
radiation workers. This restrospective cohort mortality study, takes
into account occupational doses of workers engaged in nuclear technology
development and employed for at least 6 months at Rocketdyne (Atomics
International, Boeing) Facilities in California, from 1948-1999. It
includes radiation received prior to and subsequent to work at Rocketdyne
from both company records and linkages with national
dosimetry data sets. Workers were monitored for internal and external
radiation. Internal doses were obtained from bioassay data
collected over a 40 year period and evaluated using
International Commission on Radiological Protection (ICRP) biokinetics
models. The 'external' file contains annual total gamma, x-rays and
neutron doses for workers monitored for external radiation. Overall,
this study showed that radiation exposure has not caused a detectable
increase in cancer deaths in this population, but results are limited by
small numbers and relatively low career doses and
risk estimates based on nuclear worker data must be
interpreted cautiously if internally deposited
radionuclides and occupational doses received elsewhere are not considered.
Historically this facility was involved in a wide variety of research and development activities for promoting the use of coal, including coal preparation and combustion, coal gasification, coal liquefaction, flue gas clean-up, and oil shale activities. Exposures to organic and inorganic chemicals resulted from the major activities and associated research and development support activities at the Pittsburgh Energy Technology Center (PETC). In March 1992 workers at PETC expressed concern that workplace exposures may be having an adverse effect on their health. Specifically, they were concerned about the possibility of an increase in heart attacks among former workers, the potential cumulative health effects of chemical exposures, and a possible relationship between exposure to perchloroethylene and psychological effects such as nervous tension, irritability, and anger.
The objectives of the Off-Site Radiation Exposure Review Project (ORERP)
were to collect and organize data pertaining to off-site fallout from weapons testing from 1951 until 1975 at the Nevada Test Site (NTS). Another objective was to reevaluate the radiation dose received by off-site residents using computer models for the transport of radionuclides from their deposition on the ground or vegetation to its ingestion by humans through food and for organ doses resulting from ingestion, inhalation or deposition on the skin. Also, the models required various data relating to fallout transport and population demographics as input. Four of the basic data files used as input to these dose estimation models and included in the CEDR data file set collection are the Town Data Base file (TOWNDB), the County Data Base file (CNTYDB) and the Lifestyle Survey Data Base files (LFSDEMOG and LFSFARM). The working data file set was prepared by Desert Research Institute.
Death Summary Tables show the number of deaths occurring in various groupings
derived from the ICD classification used in an epidemiologic study. They help
researchers quickly determine if that particular data file set is of
interest to them. Death Summary Tables
for most analytic studies are accessible via their CEDR data file sets:
This study analyzed the relationship between external ionizing radiation and leukemia mortality among civilian employees of the PNS to help determine whether occupational exposures to radiation were associated with a risk for leukemia. Exposure assessments for benzene and carbon tetrachloride were also completed since these chemicals might also cause leukemia.
The case-control study results suggest that leukemia mortality risk increased with increasing cumulative occupational ionizing radiation dose among PNS workers. The magnitude of increase in leukemia risk is consistent with other radiation epidemiology study results. Workers potentially exposed to benzene or carbon tetrachloride for longer periods of time also appear to have greater risk of death from leukemia. Uncertainty in the risk estimates, i.e., the rather wide confidence intervals, is attributed to the relatively small number of leukemia deaths (34) among radiation-monitored workers and reliance on job titles and shops to estimate benzene and carbon tetrachloride exposures instead of individual monitoring results for these chemicals.
Study of Mortality and Radiation-Related Risk of Cancer Among Workers at the Idaho National Engineering and Environmental Laboratory (INEEL)
The Idaho National Engineering and Environmental Laboratory (INEEL)
is a large U.S. Department of Energy (DOE) facility near Idaho Falls, Idaho. Since it's construction in 1949 the INEEL
has conducted a wide variety of activities, including engineering and basic scientific research, nuclear reactor design
and testing, nuclear material chemical processing, and the construction, servicing and demolition of large-scale facilities.
In addition, the U.S. Navy maintains its Naval Reactors Facitlity (NRF) at the INEEL, where research and testing of Navy
ship reactors occurs, as well as training of military and civilian personnel involved in the naval surface ship and submarine
program. An epidemiologic cohort mortality study was initiated to evaluate hazards associated with ionizing radiation
and other exposures amoung civilian employees at the INEEL facility.
Documents pertaining to this project are accessible from the CEDR resource
This study evaluates the influence of age at exposure on radiation risk
estimates in an updated follow up of workers at the plutonium production
facility in Hanford, WA. A cohort of 26389 workers hired between 1944
and 1978 was followed through 1994 to ascertain vital status and causes
of death. External radiation dose estimates were derived from personal
dosimeters. Poisson regression was used to estimate associations between
mortality and cumulative external radiation dose at all ages, and in
specific age ranges. A total of 8153 deaths were identified, 2265 of which
included cancer as an underlying or contributory cause. The study concluded
that associations between radiation and cancer mortality in this cohort
are primarily a function of doses at older ages and deaths from lung
cancer. The association of older age radiation exposures and cancer
mortality is similar to observations from several other occupational
studies.
This report examines cancer mortality among more than 400,000 nuclear industry
workers in 15 countries including workers from three U.S. Department of
Energy (DOE) facilities: Hanford, the Oak Ridge National Laboratory (ORNL),
and the Idaho National Laboratory (formerly called Idaho National
Engineering and Environmental Laboratory, INEEL). The three DOE sites were
selected for inclusion by IARC study subcommittees because workers at those
sites were exposed to primarily external sources of radiation and the data
were readily available.
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Last modified: January 22, 2008