An Ecologic Study of Nitrate in Municipal Drinking Water and Cancer Incidence in Trnava District, Slovakia

摘要: Contamination of drinking water by nitrate is an evolving public health concern since can undergo endogenous reduction to nitrite, and nitrosation nitrites form N-nitroso compounds, which are potent carcinogens. We conducted ecologic study determine whether levels in were correlated with non-Hodgkin lymphoma cancers the digestive urinary tracts agricultural district (Trnava District; population 237,000) Slovak Republic. Routinely collected data (1975-1995) for villages using supplies computerized, each village was categorized into low (0-10 mg/L), medium (10.1-20 or high (20.1-50 mg/L) average total water. Observed cases cancer these ascertained through registry time period 1986-1995. Standardized incidence ratios (SIRs) 95% confidence intervals (CI) all selected sites calculated indirect standardization age- sex-specific rates from entire district. For women, SIRs increased (SIR=0.87; CI 0.72-0.95) (SIR=1.07; 1.00-1.13) (SIR=1.14; 1.06-1.22) (P trend <0.001); there a similar men (SIR=0.90; 0.81-0.99) (SIR=1.08, 1.02-1.16), but not (SIR=0.94; 0.88-1.02), <0.001). This pattern (from level) also seen stomach women (0.81, 0.94, 1.24; P trend=0.10), colorectal (0.64, 1.11, 1.29; <0.001) (0.77, 0.99, 1.07; trend=0.051), (0.45, 0.90, 1.35; trend=0.13) (0.25, 1.66, 1.09; trend=0.017). There no associations kidney bladder cancer. These support hypothesis that positive association between