Cancer mortality in towns in the vicinity of incinerators and installations for the recovery or disposal of hazardous waste

Abstract

BACKGROUND: Waste treatment plants release toxic emissions into the environment which affect neighboring towns. OBJECTIVES: To investigate whether there might be excess cancer mortality in towns situated in the vicinity of Spanish-based incinerators and installations for the recovery or disposal of hazardous waste, according to the different categories of industrial activity. METHODS: An ecologic study was designed to examine municipal mortality due to 33 types of cancer, across the period 1997-2006. Population exposure to pollution was estimated on the basis of distance from town of residence to pollution source. Using Besag-York-Mollié (BYM) regression models with Integrated Nested Laplace approximations for Bayesian inference, and Mixed Poisson regression models, we assessed the risk of dying from cancer in a 5-kilometer zone around installations, analyzed the effect of category of industrial activity, and conducted individual analyses within a 50-kilometer radius of each installation. RESULTS: Excess cancer mortality (BYM model: relative risk, 95% credible interval) was detected in the total population residing in the vicinity of these installations as a whole (1.06, 1.04-1.09), and, principally, in the vicinity of incinerators (1.09, 1.01-1.18) and scrap metal/end-of-life vehicle handling facilities, in particular (1.04, 1.00-1.09). Special mention should be made of the results for tumors of the pleura (1.71, 1.34-2.14), stomach (1.18, 1.10-1.27), liver (1.18, 1.06-1.30), kidney (1.14, 1.04-1.23), ovary (1.14, 1.05-1.23), lung (1.10, 1.05-1.15), leukemia (1.10, 1.03-1.17), colon-rectum (1.08, 1.03-1.13) and bladder (1.08, 1.01-1.16) in the vicinity of all such installations. CONCLUSIONS: Our results support the hypothesis of a statistically significant increase in the risk of dying from cancer in towns near incinerators and installations for the recovery or disposal of hazardous waste.