Project update: evaluating the community health legacy of WWI chemical weapons testing.

The Spring Valley community of Washington, District of Columbia, was built on the site of a World War I chemical weapons lab where testing activities had distributed arsenic to surface soil and waste disposal had resulted in localized subsurface contamination. In previous work, findings were suggestive of potential site-related health issues, although no evidence of cancer clustering was found. In follow-up, we updated the community health assessment and explored time trends for several arsenic-related cancers. Health indicators continue to be very good in Spring Valley. For all major causes of mortality, Spring Valley rates were lower than United States (US) rates with most substantially lower (20-80 %); rates for heart diseases, Alzheimer's, and essential hypertension and related kidney disease were only slightly lower than US rates (3-8 %). Incidence and mortality rates for the selected cancers in the Spring Valley area were lower than US rates. Small non-statistically significant increasing time trends were observed in Spring Valley for incidence of two arsenic-related cancers: bladder and lung and bronchus. A moderate statistically significant increasing rate trend was observed for lung and bronchus cancer mortality in Spring Valley (p < 0.01). Lung and bronchus cancer mortality rates were also increasing in the Chevy Chase community, the local comparison area closely matched to Spring Valley on important demographic variables, suggesting that the observed increases may not be site-related. A full profile of common cancer site rates and trends for both study areas was suggested to better understand the rate trend findings but no epidemiological study was recommended.