Drinking from private wells across the United States may have to cease if findings of a study linking it to a long recognised excess mortality from bladder cancer in New England are confirmed.
The link between residual bladder cancer mortality and use of private wells was found in white men (Pearson's correlation coefficient r = 0.42) and women (r = 0.48) in New England and New York and New Jersey (r = 0.49, 0.62, respectively) after adjusting for population density, which is positively associated with bladder cancer in the United States. Thus it seems possible that greater exposure to carcinogens in well water or some other close marker causes bladder cancer, though this needs to be clarified by non–ecological studies.
The study compared age adjusted bladder cancer mortality in white men and women during 1985–99 and the proportion of people obtaining drinking water from private wells in New England and some other states, as calculated from data on water use in 1970. This was the first year that national data on water use included private wells and provides a 15 year minimum interval with the mortality data.
Excess bladder cancer mortality has been known in New England since the 1950s, though its exact cause is unknown. Use of private wells here is prevalent. Water from them does not have to meet federal standards for drinking water, and the common practice in New England of drilling the wells into fractured crystalline bedrock aquifers increases the chances of natural contaminants such as arsenic gaining access. Arsenic in drinking water has been linked to bladder cancers elsewhere in the world.
▴ Ayotte JD, et al.Journal of Epidemiology and Community Health 2006; 60:168–172.
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