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1
Introduction
Camp Lejeune is a U.S. Marine Corps base that covers about 233 square miles in Onslow County,
North Carolina. It was established in the early 1940s and is the site of six major Marine Corps commands
and two U.S. Navy commands, including reconnaissance, intelligence, infantry, artillery, and amphibious
units. In the early 1980s, the Marine Corps discovered that the drinking-water systems that supplied two
areas of housing at Camp Lejeune (Tarawa Terrace and Hadnot Point) were contaminated with volatile
organic compounds (VOCs). The major contaminants of concern were identified as the solvents trichloro-
ethylene (TCE) and perchloroethylene (PCE).1
Investigation into the drinking-water contamination began in 1980, when a routine test was con-
ducted for trihalomethanes, which are produced as byproducts of water-treatment processes. Results indi-
cated that other contaminants were present, including TCE, PCE, and other VOCs. Further investigation
revealed that wells serving Tarawa Terrace were contaminated with PCE from an off-base dry-cleaning
operation because of accidental spills and improper disposal of PCE. The contamination probably began
when dry-cleaning operations began in 1953 (Maslia et al. 2007). The wells serving the Hadnot Point wa-
ter system had multiple sources of contamination and multiple contaminants, the most important of which
was TCE. Sources of the contamination included on-base spills at industrial sites and leaks from under-
ground storage tanks and drums at dumps and storage lots. The Hadnot Point water-treatment plant began
operating in 1943, but no estimates have yet been made of when the contamination might have begun.
The contaminated wells in both systems were removed from service during 1984-1985.
The residential areas served by the Tarawa Terrace and Hadnot Point water systems consisted
primarily of enlisted-personnel family housing and barracks for unmarried service personnel. Thus, many
of the exposed were young members of families and people of reproductive age. Both water systems also
served base administrative offices, schools, and recreational areas. In addition, the Hadnot Point water
system served the base hospital and an industrial area, periodically supplemented water supply to the Hol-
comb Boulevard system in summer months (Bove and Ruckart 2008), and temporarily supplied water to
the Holcomb Boulevard water system for a 2-week period during an emergency in 1985 (GAO 2007).
The number of people that lived or worked in the areas served by the contaminated water systems has not
yet been determined.
There has been considerable controversy over the drinking-water contamination at Camp Le-
jeune. Questions have been raised about when the contamination was discovered, whether appropriate
action was taken by the Marine Corps and the Department of the Navy (the department under which the
Marine Corps operates), and whether information about the contamination was disclosed in timely and
appropriate ways. Some people who became ill or whose families or friends became ill or died have
sought to learn whether the contaminated drinking water might be to blame. They have also questioned
whether the investigations that were conducted were the most appropriate ones and whether studies that
1
PCE is also known as tetrachloroethylene or Perc.
23
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Contaminated Water Supplies at Camp Lejeune—Assessing Potential Health Effects
24
are under way will answer their questions definitively. Hundreds of former residents and employees of
Camp Lejeune have filed claims with the Department of the Navy.
Several investigations have been performed on issues related to the discovery of the contamina-
tion at Camp Lejeune. A brief overview of the investigations follows.
INVESTIGATIONS
Camp Lejeune Studies
Health Investigations
A sequence of health investigations and studies were conducted by the Agency for Toxic Sub-
stances and Disease Registry (ATSDR) after the U.S. Environmental Protection Agency (EPA) added
Camp Lejeune to its National Priorities List in October 1989. A public-health assessment evaluated expo-
sures and potential risks at three sites on the base, including the sites served by the contaminated drink-
ing-water systems (ATSDR 1997a). ATSDR judged that exposure to VOCs in drinking water was
unlikely to pose health risks to adults but raised questions about risks to children who may have been ex-
posed in utero. A followup study found no overall association between exposure and pregnancy outcome
but reported that male infants were small for their gestational age (ATSDR 1998). Similarly, Sonnenfeld
et al. (2001) found no overall association with pregnancy outcome but reported that infants of some
groups of mothers who were exposed during pregnancy had lower birth weights.
ATSDR is now studying children born at Camp Lejeune in 1968-1985 to determine whether ex-
posure to VOCs in drinking water is related to specific birth defects and childhood cancers. Health effects
under consideration include spina bifida, anencephaly, cleft lip, cleft palate, childhood leukemia, and
childhood non-Hodgkin lymphoma. The study will also include modeling of the contaminants and water-
supply systems in an attempt to provide better estimates of which study participants might have been ex-
posed and at what concentrations. The water modeling conducted to date and ATSDR’s health studies are
evaluated in Chapters 2 and 8, respectively.
Other Investigations
Several federal inquires on the contamination of the water supplies at Camp Lejeune were con-
ducted. The inquiries were not health investigations or evaluations of scientific issues but rather were fo-
cused on activities surrounding the discovery and handling of the situation. A short summary is presented
here to give the reader some background, but the issues are outside the scope of the current report and the
investigations were not used or evaluated by the committee. One inquiry was conducted in 2004 by a
panel chartered by the Marine Corps to review the facts surrounding the discovery of the drinking-water
contamination and actions taken (Drinking Water Fact-Finding Panel for Camp Lejeune 2004). The panel
found that the Marine Corps responded appropriately with the information available and found no evi-
dence that an attempt was made to cover up evidence of the contamination. However, the panel concluded
that the Navy should have been more aggressive in providing technical expertise to the Marine Corps so
that it could understand the significance of the contamination, that communication between Camp Le-
jeune officials and between base officials and Navy technical support was not always adequate, and that
communication with former residents did not provide enough details to characterize the contamination
fully.
EPA conducted two inquiries. One, completed in 2005, was the EPA Office of Inspector Gen-
eral’s investigation into complaints about EPA’s response to Freedom of Information Act requests about
the Camp Lejeune contamination and other issues regarding EPA’s responsibilities. The Office of Inspec-
tor General found that EPA’s responses to the information requests were not handled appropriately but
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Introduction 25
also found that the other complaints were without merit or were outside the purview of EPA. The second
EPA inquiry was conducted in 2003-2005 by its Criminal Investigation Division, which sought to deter-
mine whether any violations of federal laws had occurred, reasons for funding delays, and whether re-
cords and data were falsified or mishandled. The division was critical of some actions taken by Marine
Corps and Navy officials but found that no federal laws were violated. The case was also forwarded to the
Department of Justice for evaluation, which decided not to seek criminal prosecution.
The U.S. Government Accountability Office (GAO 2007) also assessed activities related to drink-
ing-water contamination at Camp Lejeune. In its report to Congress, GAO described efforts to identify
and address the contamination, activities that resulted from the discovery of the contamination, the gov-
ernment’s actions, and the design of the current ATSDR study.
Contaminant Studies
The two drinking-water contaminants of greatest concern—TCE and PCE—are environmental
contaminants used in occupational settings and commonly found at hazardous-waste sites. The two sol-
vents have similar metabolites that are thought to be largely responsible for the toxicity observed after
exposure. Studies have shown that TCE and PCE can have a number of adverse health effects, including
cancer, when animals are exposed under experimental conditions. Epidemiologic studies of workers ex-
posed to the solvents in occupational settings have been conducted, and there is a growing body of litera-
ture on community exposures to TCE and PCE in drinking water. In addition, several federal and state
agencies have conducted or are conducting human health risk assessments or analyses of TCE and PCE.
For example, ATSDR has released toxicologic profiles of TCE (ATSDR 1997b) and PCE (ATSDR
1997c), the International Agency for Research on Cancer has an evaluation of dry-cleaning and chlorin-
ated solvents (IARC 1995), the California Environmental Protection Agency has a public-health goal for
PCE in drinking water (Cal EPA 2001), and EPA is updating its human health risk assessments of TCE
and PCE.
The Institute of Medicine (IOM 2003) performed a comprehensive assessment of the long-term
adverse health outcomes associated with exposure to various solvents as part of its evaluation of agents to
which Gulf War veterans were exposed, including TCE and PCE. The literature used in the IOM assess-
ment consisted primarily of occupational studies of workers chronically exposed to solvents. Few of the
studies included women or children. Animal data were used for making judgments about the biologic
plausibility of associations but were not used as part of the weight-of-evidence approach.
In 2006, the National Research Council published Assessing the Human Health Risks of Tri-
chloroethylene: Key Scientific Issues (NRC 2006); it was based on a study sponsored by EPA, which was
seeking guidance on updating its risk assessment of TCE. The report examined issues critical for develop-
ing an objective, scientifically based health risk assessment of TCE. As indicated above, EPA has not yet
released a revised risk assessment of TCE.
COMMITTEE’S TASK
At the request of Congress, the Navy sponsored this study by a committee of the National Re-
search Council to review the scientific evidence on associations between adverse health effects and his-
torical data on prenatal, childhood, and adult exposures to contaminated drinking water at Camp Lejeune,
North Carolina. The committee was asked to assess the strength of evidence in establishing a link or asso-
ciation between exposure to TCE, PCE, and other drinking-water contaminants and each adverse health
effect suspected to be associated with such exposure. For each health effect reviewed, the committee was
to determine, to the extent practicable with the available scientific data, whether a statistical association
between contaminant exposure and the health effect exists, whether a plausible biologic mechanism or
other evidence of a causal relationship between contaminant exposure and effect exists, the strength of
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Contaminated Water Supplies at Camp Lejeune—Assessing Potential Health Effects
26
evidence for a causal inference for each health effect, and other scientific considerations that may help the
Navy to set priorities for future activities.
The committee's review was to include an evaluation of the toxicologic and epidemiologic litera-
ture on adverse health effects of TCE and PCE, including studies of populations exposed to similar con-
centrations of the contaminants of concern; risk-assessment reports from government agencies; recent
literature reviews by the National Research Council, IOM, and other groups; completed and current
ATSDR studies at Camp Lejeune; and published meta-analyses. In its evaluation of previous and current
health studies of residents of Camp Lejeune, the committee was asked to review the appropriateness of
the study question, design, analysis, results, and conclusions.
COMMITTEE’S APPROACH
To address its task, the committee held two public meetings in September and November 2007 to
gather information from the sponsor and other parties knowledgeable about the contamination and related
issues. The Marine Corps made presentations on the drinking-water contamination at Camp Lejeune and
addressed questions about the scope of work. Presentations were also made by ATSDR on its past and
current health studies of former residents and on its current groundwater modeling activities to estimate
the exposures that occurred historically at the base. GAO reported on its investigation into actions taken
by various agencies in response to the discovery of the contamination. Representatives of ATSDR’s
community-assistance panel informed the committee about the panel’s activities and about the specific
health concerns raised by former residents. There were also open-microphone sessions to hear from for-
mer residents and employees of the base about their concerns and to learn about information that they had
that was relevant to the study. The committee visited Camp Lejeune to get firsthand information on the
affected housing areas; information on the location of wells, water-treatment plants, and base boundaries;
and other site information to use in its evaluation. A third public meeting was held in September 2008 to
hear about ATSDR’s assessment of the feasibility of conducting additional epidemiologic studies.
The current report expands on previous reviews of the Camp Lejeune drinking-water contamina-
tion by providing an assessment of multiple lines of research to ascertain the likelihood that exposure to
the contaminated water supply is associated with adverse health effects. The evidence reviewed included
exposure evaluations performed by other organizations, raw data on the contaminants measured in the
water supply, studies of contaminants in laboratory animals, studies of human populations exposed to the
contaminants, and studies of the Camp Lejeune population.
As specified in the task, the committee also took advantage of the comprehensive literature re-
views and health risk assessments that were performed by other agencies. The report by IOM (2003) fig-
ured prominently in the committee’s evaluation of the epidemiologic evidence because it provided a com-
prehensive review of the epidemiologic research on TCE and PCE and individual health outcomes and
categorized the evidence according to an established scheme accepted by the Department of Veterans Af-
fairs in evaluating risks to veterans of the Vietnam War and the Gulf War. The committee updated IOM’s
review, modified categorizations where appropriate, reviewed literature on pregnancy outcomes in
women exposed during pregnancy (a population excluded from IOM’s review because pregnant women
are not deployed), and expanded on IOM’s approach by explicitly considering how evidence from the
animal literature adds to the weight of evidence and by considering the exposures that were likely to have
occurred at Camp Lejeune.
The committee also considered the possible contribution of additional research to inform Marine
Corps decisions about what actions to take about the past water-supply contamination and its possible
contribution to scientific knowledge. The committee approached that question by considering possible
research activities, evaluating their feasibility, and assessing whether the results would substantively in-
form decisions by the Marine Corps or contribute to scientific knowledge.
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Introduction 27
ORGANIZATION OF THE REPORT
The report first discusses the individual elements of the committee’s review of the drinking-water
contamination at Camp Lejeune (Chapters 2-7) and then considers the elements together to draw conclu-
sions about whether particular health outcomes can be linked to the exposures that occurred. Chapter 2
evaluates what is known about the possible exposures of the populations that lived or worked in areas
served by the contaminated water systems. On the basis of what is known about the primary contaminants
of concern, Chapter 3 discusses some of the biochemical changes that occur after the contaminants enter
the body and how they or their metabolic products are transported in the body; it also considers popula-
tions that might be more susceptible to effects of the contaminants, lifestyle factors that affect how the
contaminants interact in the body, and how the contaminants interact with each other and with other
chemicals in the body. In reviewing what adverse health effects might result from exposure to the con-
taminants, the committee first reviews the toxicology literature in Chapter 4, which involves primarily
studying effects in animals given the contaminants under experimental conditions. Chapter 5 reviews
studies of human subjects who were exposed to the same chemicals that contaminated the Camp Lejeune
drinking-water system, mainly studies of occupational exposure. Chapter 6 evaluates studies of popula-
tions exposed to similar contaminants via drinking water to see whether any inferences that would be ap-
plicable to the Camp Lejeune situation can be drawn. The toxicologic and epidemiologic evidence is con-
sidered together in Chapter 7 to determine the strength of the available evidence on particular health
outcomes. Chapter 8 deals specifically with studies of exposure and health effects in former residents of
Camp Lejeune, including completed, current, and proposed studies by ATSDR.
