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CDC Public Health Activities
Conducting public health activities at Department of Energy (DOE) sites
is the responsibility of two groups in the Centers for Disease Control
and Prevention (CDC):
National Institute for Occupational Safety and Health
(NIOSH)
The National Institute
for Occupational Safety and Health (NIOSH) has a broad program of
occupational health research across the DOE complex. NIOSH interacts with
DOE and DOE workers in three ways.
NIOSH Studies on the Health of Oak Ridge Workers
Researchers at NIOSH, in collaboration with others, have conducted numerous
studies of health effects among workers at the Oak Ridge Reservation.
Findings of the studies include the following :
- Mortality Among Workers at Oak Ridge National
Laboratory
The Oak Ridge National Laboratory (X-l0) has been the subject of long-term
epidemiologic study. A mortality analysis of 8,375 white males through
1977 found no cause of death that was higher than expected based on
the U.S. general population. However, leukemia mortality was related
to length of employment in engineering and maintenance jobs. A follow-up
study reported that the death rate from leukemia through 1984 was greater
than the U.S. rate, particularly among workers monitored for internal
radiation contamination.
A positive trend was reported for all cancers combined by level of cumulative
external dose but not for leukemia. In the most recent study of deaths
through 1990, none of the rates for the four causes of death reported,
all causes of death combined, all cancers combined, lung cancer, and
leukemia, was higher than the corresponding U.S. rates.
A recent study of deaths through 1990 reported that radiation doses
received after age 45 years strongly predict the all cancers combined
mortality rate; an earlier X-10 study noted that employees age 65 years
and older at exposure were at higher risk.
- Mortality of Workers at a Nuclear Materials
Production Plant at Oak Ridge (Y-12)
The first study of Y-12 workers included 18,869 white males who ever
worked at the plant and mortality through 1974 was identified. The second
study was restricted to 6,781 men who worked at least 30 days with mortality
through 1979. A third study was expanded to include 10,597 nonwhite
workers and females with deaths through 1990. The death rate from lung
cancer was higher than the U.S. rate in the most recent two studies.
Analysis of deaths through 1979 did not confirm positive trends for
any cause of death with either external or internal exposure to ionizing
radiation although a weak trend was observed for lung cancer.
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 and 91 females received acute exposures. 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.
- Mercury Workers Health Studies
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.
A total of 502 mercury workers were also involved in a clinical neurology
study. Clinical measurements revealed some deficiencies in neurological
function particularly among those workers with the highest exposures,
but these were not associated 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.
- Morbidity and Mortality Among Workers Employed
at a Uranium Gaseous Diffusion Facility at Oak Ridge (K-25)
Studies of workers at K-25 found that white males had high rates relative
to the U.S. general population for all causes of death; 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 K-25 to produce the barrier material that
separates and enriches uranium. Death rates for 814 nickel workers who
made the barriers were compared to 1,600 controls. No differences in
the death rates for the exposed and non-exposed workers by cause of
death through 1972 were detected. A later study compared the mortality
of the 814 nickel workers through 1977 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.
- Follow-Up of Morbidity Study of Bladder Cancer
and Chemical Exposures at K-25, Oak Ridge, Tennessee
Epoxy resins and solvents were common exposures among K-25 gas centrifuge
workers. In Phase I of a study of centrifuge workers, 263 workers with
the most exposure were compared with 271 workers with no exposure at
the plant during the same period. The centrifuge process workers reported
five bladder cancers versus none reported by the non-centrifuge group.
The standardized incidence rate ratio was 7.8 for process workers versus
comparison workers. In Phase II of the study,
a larger group, who had lower levels of exposure to the centrifuge process,
was studied. One additional case was found in a centrifuge worker and
two additional cases were found in maintenance workers who were assigned
to work in centrifuge areas. An equal number of cases of bladder cancer
were found in the comparison group in Phase II.. A specific cause for
the increase in bladder cancer was not identified.
- Studies of Combined Oak Ridge Facilities (Tennessee
Eastman Corporation, Y-12, X-10, K-25)
Several studies have considered all ORR workers, the most recent one
updated mortality through 1984. Mortality from all causes of death combined
and all cancers combined were similar to overall U.S. rates. There were
substantial differences in death rates among workers at the various
ORR plants, particularly the rates for lung cancer, leukemia and other
lymphatic cancer. Within the second study, data for 28,374 workers at
X-10 and Y-12 were analyzed and positive trends were reported with increasing
external radiation dose for all causes of death combined and all cancers
combined.
Three studies of brain cancer across the four ORR facilities have been
published. The exposure analysis of 26 chemicals found that none were
positively associated with brain cancer. No positive trends for brain
cancer were found 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 of increasing cancer with the number of
years worked.
Mortality data through 1974 and through 1989 were analyzed for about
1,059 white male welders at ORR. No death rates were higher than the
U.S. rate through 1974. When deaths through 1989 were considered, welders
bad higher rates of 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.
- Multi-Site Multiple Myeloma Case-Control Study
A multi-site study of multiple myeloma deaths included workers from
X-10. Although the death rate was not higher than expected, higher risks
were encountered by workers whose radiation exposures occurred after
age 45.
- Childhood Leukemia Case-Control Study
A study of the potential association between paternal exposure to ionizing
radiation and risk of childhood cancer found no link between leukemia
and paternal employment at ORR. Children whose fathers worked at the
Hanford Nuclear Reservation were more likely to get CNS (central nervous
system) cancer than children whose fathers worked at other sites, including
ORR, but this finding was based on small numbers and was not statistically
significant.
- Cyanide Health Hazard Evaluation at K-25
A NIOSH health hazard evaluation, requested by K-25 site employees,
investigated possible worker exposure to cyanides. The evaluation indicated
that employees are not occupationally exposed to hydrogen cyanide, cyanide
salts, or a wide variety of other compounds that contain the cyanide
ion.
- The Oak Ridge National Laboratory, sponsored by a NIOSH grant, investigated
statistical estimation of dose from daily and weekly dosimetry data
for ORR radiation workers included in previous epidemiologic studies.
The study found that diferences between the two methods were substantial,
and recommended methods of reducing uncertainly for some estimates.
- Improved Systems for Worker Exposure Surveillance
The Oak Ridge Associated Universities, under a NIOSH grant, developed
a project at ORR to develop a system for the prioritization of industrial
hygiene and medical surveillance efforts. The Worker Exposure Surveillance
System (WESS) was designed for easy data merger with traditional occupational
health systems utilizing environmental level analyses, occupational
titles, and area descriptors.
- Work Histories Evaluating New Participatory
Methods
Exposure History for the Construction Trades (WHEP). The University
of Cincinnati, under a NIOSH grant, created an exposure history for
the construction trades at ORR, which was aimed at improving worker
recall of complex occupational exposures across a large number of short-term
workplace assignments. New techniques were usedto establish guidelines
and formats for personal work histories. This study has recently been
completed and the results will be published in 2001.
- Exposure Assessment of Hazardous Waste, Decontamination
and Decommissioning, and Clean-up Workers----Phase I Feasibility Study
Exposure assessment of hazardous waste, decontamination and decommissioning,
cleanup workers (HAWW). Feasibility studies at seven DOE sites, including
ORR, determined that the availability of records to identify workers
and their primary activities, exposures, work histories, and medical
information varied significantly from site to site. The necessary information
to conduct exposure assessment, hazard surveillance, or epidemiology
studies of remediation workers is currently not readily available. Within
sites, data systems are fragmented and data management is inconsistent
in the current environment of decentralized management and increased
subcontracting.
- Prevention of Stress and Health Consequences
of Downsizing and Reorganization
Prevention of stress and health consequences of downsizing (STDN). The
effects of downsizing on organizational climate, worker health, and
performance were studied at several DOE sites, including ORR. Data gathering
included interviews, workplace observations, employee discussion groups,
an employee survey distributed to more than 10,500 employees, and a
historical record review. Researchers identified opportunities to reduce
job stress that could lead to improved employee health and organizational
well-being. Suggested intervention strategies were proposed for further
research.
- Mortality Among Female Nuclear Weapons Workers
Study of mortality among female nuclear workers (MAFN). A study of female
workers from 12 DOE plants, including ORR, was combined in a cohort
mortality study, and risk estimates were developed for exposure to ionizing
radiation or to chemical hazards. For the entire pooled cohort, mortality
from mental disorders, diseases of the genitourinary system, and from
ill-defined conditions was higher than expected. External ionizing radiation
exposure in these workers appeared to be associated with increased relative
risk for leukemia and, to a lesser degree, associated with increased
relative risks for all cancers combined and for breast cancer.
- Multiple Myeloma Case-Control Study at K-25
Plant
DOE's epidemiologic surveillence assess the overall health of the current
DOE work force at 14 DOE sites, including ORR (Y-12), Oak Ridge National
Laboratory (X-10), and East Tennessee Technology Park (K-25). The goal
is to identify groups of workers that may be at increased risk for occupation-related
injuries.
- Cohort Mortality Study of DOE Chemical Laboratory
Workers
An indendent panel of nationally recognized occupational health physicians
is conducting individual medical evaluations to assess occupational
health complaints and symptoms of 53 current an former Lockheed Martin
Energy Systems workers at the East Tennessee Technology Park (formerly
called the K-25 site). These medical evaluations include reviews of
prior health studies; visits to workers' workplaces and surroundings;
work history interviews with individual workers; reviews of worker medical
records; physical examinations; and sepcialized follow-up inquiries
and testing.
- The DOE Beryllium Worker Medical Surveillance Program, which includes
an intensive, coordinated health-risk communication effort, is designed
to detect and diagnose chronic beryllium (CBD) among current and former
workers exposed to beryllium throughout the DOE complex, including ORR.
Information from this program is used to improve and evaluate worker
protection and control measures, to monitor trends in CBD frequency,
and to strengthen work planning to minimize worker exposures.
- DOE's Former Worker Program is a pilot program designed to provide
medical surveillance for selected former DOE workers at risk of work-related
illness as a result of exposures while working at DOE facilities. The
following projects are underway at ORR:
- The former construction worders project is led by Dr. Eula Bingham
of the University of Cincinatti in cooperation with the United Brotherhood
of Carpenters Helath and Safety Fund, the Center to Protect Workers'
Rghts, and Duke University Medical Center. The Phase I assessment
identified approximately 800 former consturction workdrs. Phase II
will focus on medical screening of workers exposed to asbestos, beryllium,
noise, silica, solvents, and heavy metals.
- The project involving former production workers from the Oak Ridge
K-25, Paducah, and Portsmouth gaseous diffusion plants is led by Dr.
Steven Markowitz of Queens College, City University of New York, and
Mr. Robert Wages of the Oil, Chemical, and Atomic Workers International
Union, in cooperation with the University of Massachussetts at Lowell.
The Phase I assessment identified approximately 1,260 former production
worders as potentially at high risk. Phase II will focus on medical
screening of workers exposed to asbestos, beryllium, bladder carcinogens,
chlorinated solvents, flourine compounds, nickel, noise, silica, uranium,
welding fumes, and heavy metals.
- DOE plans to expand the Former Worker Medical Surveillance Program
to Current workers and additional former workers at the three gaseous
diffusion plants.
National Center for Environmental Health (NCEH)
The National
Center for Environmental Health (NCEH) conducts environmental dose
reconstructions, radiation epidemiology studies, and radiation risk analysis
and communication at DOE sites.
Community Health Investigations and Activities
The NCEH conducted the following health strategies to evaluate reported
illnesses afflicting residents in communities surrounding the Oak Ridge
Reservation.
In 1983 the Tennessee Department of Health and Environment and the Centers
for Disease Control and Prevention's (CDC) National Center for Environmental
Health (NCEH) conducted a pilot survey in Oak
Ridge in response to community concerns about mercury contamination in
the East Fork Poplar Creek flood plain and the sewer line beltway. The
pilot survey concluded that residents and workers in Oak Ridge are not
likely to be at increased risk for having significantly high mercury levels.
Mercury concentrations in hair and urine samples were below levels associated
with known health effects.
In 1993 ATSDR and CDC facilitated laboratory support
from the National Center for Environmental Health at CDC for clinical
evalautions of selected patients who had been referred to Howard Frumkin,
MD, DrPH, of the Emory University School of Public Health. Dr. Frumkin
conducted individual clinical evaluations of the Oak Ridge physicians
patients and did not report any hazardous substance exposure to public
health agencies
According to the 1998 CDC health investigation
of the Scarboro community, the results of the self-reporting health
survey indicated elevated rates of asthma and wheezing. The asthma rate
was 13% among children in Scarboro, compared to national estimates of
7% among all children aged 0-18 years, and 9% among African American children
aged 0-18 years, which is less that the 14.5% Chicago rate. The wheezing
rate among children in Scarboro was 35%, compared to international estimates
of 1.6% to 36.8%.
No statistically significant association was found between exposure to
common environmental triggers of asthma (e.g.. tobacco smoke, pests, unvented
gas stoves, and dogs or cats in the home) or potential occupational exposures
(e.g., living with an adult who works at ORR or living with an adult who
works with dust and fumes and brings exposed clothes home) and asthma
or wheezing illness.
The physical examinations of 23 Scarboro children who were identified
in the survey as possibly having asthma indicated that all were generally
healthy and no urgent health problems were identified. Only one child
had a lower respiratory illness, and none were wheezing at the time of
the physical examination.
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