Abstract

Background Drinking water at U.S. Marine Corps Base Camp Lejeune, North Carolina was contaminated with trichloroethylene and other industrial solvents from 1953 to 1985.

Methods A cohort cancer incidence study was conducted of Marines/Navy personnel who, between 1975 and 1985, began service and were stationed at Camp Lejeune, North Carolina (N=154,821) or Camp Pendleton, California (N=163,484), and civilian workers employed at Camp Lejeune (N=6,494) or Camp Pendleton (N=5,797) between October 1972 and December 1985. Camp Pendleton’s drinking water was not known to be contaminated between 1972 and 1985. Individual-level information on all primary invasive cancers and in-situ bladder cancer diagnosed from 1996 to 2017 was obtained from data linkages with 54 cancer registries in the U.S. Survival methods were used to calculate hazard ratios (HRs) comparing cancer incidence between the Camp Lejeune and Camp Pendleton cohorts. Precision of effect estimates were evaluated using the 95% confidence interval (CI) ratio.

Results Cancers among Camp Lejeune Marines/Navy personnel and civilian workers totaled 12,083 (354/100,000) and 1,563 (1,301/100,000), respectively. Cancers among Camp Pendleton Marines/Navy personnel and civilian workers totaled 12,144 (335/100,000) and 1,416 (1,372/100,000), respectively.

Compared to Camp Pendleton, Camp Lejeune Marines/Navy personnel had adjusted HRs ≥1.20 with 95% CI ratios (CIRs) ≤3 for acute myeloid leukemia (HR=1.38, 95% CI: 1.03, 1.85), all myeloid cancers including polycythemia vera (HR=1.24, 95% CI:1.03, 1.49), myelodysplastic and myeloproliferative syndromes (HR=1.68, 95% CI: 1.07, 2.62), polycythemia vera alone (HR=1.41, 95% CI: 0.94, 2.11), cancers of the esophagus (HR=1.27, 95% CI: 1.03, 1.56), larynx (HR=1.21, 95% CI: 0.98, 1.50), soft tissue (HR=1.21, 95% CI: 0.92, 1.59) and thyroid (HR=1.22, 95% CI: 1.03, 1.45). Compared to Camp Pendleton, Camp Lejeune civilian workers had adjusted HRs ≥1.20 with 95% CIRs ≤3 for all myeloid cancers including polycythemia vera (HR=1.40, 95% CI: 0.83, 2.36), squamous cell lung cancer (HR=1.63, 95% CI: 1.10, 2.41) and female ductal breast cancer (HR=1.32, 95% CI:1.02, 1.71). Sensitivity analyses indicated that confounding bias due to unmeasured risk factors (e.g., smoking and alcohol consumption) is unlikely to significantly impact the findings.

Conclusion Increased risks of several cancers were observed among Marines/Navy personnel and civilian workers likely exposed to contaminated drinking water at Camp Lejeune compared to personnel at Camp Pendleton.

Competing Interest Statement

The authors have declared no competing interest.

Funding Statement

This work was supported by funding through interagency agreements with the U.S. Department of Health and Human Services, Agency for Toxic Substances and Disease Registry and the U.S. Department of the Navy. The author did not receive payment or services from a third party for any aspect of the submitted work.

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IRB of Centers for Disease Control and Prevention gave ethical approval for this work.

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Data Availability

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AbbreviationsATSDRAgency for Toxic Substances and Disease RegistryAMLacute myeloid leukemiaBOQbachelor officer quartersCDCCenters for Disease Control and PreventionCIconfidence intervalCIRconfidence interval ratioCOPDchronic obstructive pulmonary diseaseDCEt-1,2-dichloroethyleneDMDCDefense Manpower Data CenterDODUS Department of DefenseEPAUS Environmental Protection AgencyHBHolcomb Boulevard treatment plantHPHadnot Point treatment plantHRhazard ratioIARCInternational Agency for Research on CancerICD-O-3third edition of the International Classification of Diseases for OncologyMCLEPA maximum contaminant level in drinking waterMZBCLmarginal zone B-cell lymphomaNHLnon-Hodgkin lymphomaNOSnot otherwise specifiedNTPNational Toxicology Programµg/Lmicrograms per literPCEtetrachloroethylene (also known as perchloroethylene)RRrisk ratioSEERSurveillance, Epidemiology, and End Results ProgramSIRStandardized incidence ratioSSASocial Security AdministrationSSNSocial security numberTCEtrichloroethyleneTTTarawa Terrace treatment plantUSMCUnited States Marine CorpsVAU.S. Department of Veteran AffairsWHOWorld Health Organization