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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
24 Contaminated Water Supplies at Camp LejeuneâAssessing Potential Health Effects 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 ATSDRâs 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- eralâs investigation into complaints about EPAâs response to Freedom of Information Act requests about the Camp Lejeune contamination and other issues regarding EPAâs responsibilities. The Office of Inspec- tor General found that EPAâs responses to the information requests were not handled appropriately but
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- ernmentâs actions, and the design of the current ATSDR study. Contaminant Studies The two drinking-water contaminants of greatest concernâTCE and PCEâare 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. COMMITTEEâS 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
26 Contaminated Water Supplies at Camp LejeuneâAssessing Potential Health Effects 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. COMMITTEEâS 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 ATSDRâs community-assistance panel informed the committee about the panelâs 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 ATSDRâs 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 committeeâs 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 IOMâs review, modified categorizations where appropriate, reviewed literature on pregnancy outcomes in women exposed during pregnancy (a population excluded from IOMâs review because pregnant women are not deployed), and expanded on IOMâs 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.
Introduction 27 ORGANIZATION OF THE REPORT The report first discusses the individual elements of the committeeâs 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.