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

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. This study was funded by Spain's Health Research Fund (Fondo de Investigación Sanitaria — FIS 080662 and FIS CP11/0012) and ISCIII EPY 1398/09, and formed as part of the MEDEA project (Mortalidad en áreas pequeñas Españolas y Desigualdades socio-Económicas y Ambientales — Mortality in small Spanish areas and socio-economic and environmental inequalities). Sí