Drinking water, fluid intake, and bladder cancer in western New York.

Fluid intake and consumption of specific beverages were investigated in a study of 351 white male cases for whom transitional cell carcinoma of the bladder had been confirmed histologically during the time period from 1979 to 1985. A total of 855 white male controls was selected from Erie, Niagara, and Monroe counties of western New York state. Total fluid consumption was composed of alcoholic beverages, bottled beverages, soda, milk, coffee, tea, all juices, and glasses of tap water. Tap water included coffee, tea, juices, and glasses of water taken directly from the tap. Total fluid consumption was found to be a strong risk factor for bladder cancer when a number of potential confounding risk factors were controlled for. Risks were higher among those who were less than 65 y of age (odds ratio [OR] = 6.3, 95% C.I. = 2.8-14.0). The OR was 3.4 (95% C.I. = 1.8-6.2) for the highest quartile of fluid consumption among those 65 y of age and older. The tap water component was associated with increased risk in both age categories, and there was a clear dose-response relationship. Risks associated with tap water consumption were higher among those who never smoked cigarettes. Both biological and nonbiological explanations for these results are evaluated. The findings suggest implications for public health, but the limitations of the present investigation preclude definitive conclusions and stress the urgency for replication.