Evaluating the community health legacy of WWI chemical weapons testing

Spring Valley, Washington, DC, was built over a World War I chemical weapons development site. Testing activities caused wide dispersal of arsenic in soil and waste disposal resulted in localized subsurface contamination. Spring Valley presents an interesting case study, a contaminated physical environment, but a strongly health-protective social environment. To address a possible "healthy community" bias we selected a nearby comparison community with similar health-protective characteristics. Our study included a community health assessment, a spatial analysis of disease clustering and a chemical hazard assessment. Community health in Spring Valley is good. Rates of major causes of mortality and incidence of selected cancers are 20-70% lower than the nation's. Rates of hypertension and related kidney disease mortality and certain potentially arsenic-related cancers are slightly elevated in Spring Valley over a comparison community. Registry-confirmed cancers are not more likely to cluster in higher contamination areas, odds ratio (95% Confidence Interval) = 0.60 (0.30, 1.11). Chemicals detected in disposal pits are associated with cancer, kidney, neurological and blood effects. In context of a healthy community, the elevated rates of certain mortality and cancer outcomes warrant continued monitoring. Follow-up on kidney, neurological and blood diseases was recommended. Urban environments are complex with close proximity of residents to a wide variety of commercial and government activities, past and present. Each community will have a mix of health-damaging and health protective factors. Our assessment combined descriptive and analytical epidemiology and environmental risk analyses and represents a flexible tool kit adaptable to unique community conditions.