Mortality due to lung, laryngeal and bladder cancer in towns lying in the vicinity of combustion installations.

BACKGROUND: Installations that burn fossil fuels to generate power may represent a health problem due to the toxic substances which they release into the environment.
OBJECTIVES: To investigate whether there might be excess mortality due to tumors of lung, larynx and bladder in the population residing near Spanish combustion installations included in the European Pollutant Emission Register.
METHODS: Ecologic study designed to model sex-specific standardized mortality ratios for the above three tumors in Spanish towns, over the period 1994-2003. Population exposure to pollution was estimated on the basis of distance from town of residence to pollution source. Using mixed Poisson regression models, we analyzed: risk of dying from cancer in a 5-kilometer zone around installations that commenced operations before 1990; effect of type of fuel used; and risk gradient within a 50-kilometer radius of such installations.
RESULTS: Excess mortality (relative risk, 95% confidence interval) was detected in the vicinity of pre-1990 installations for lung cancer (1.066, 1.041-1.091 in the overall population; 1.084, 1.057-1.111 in men), and laryngeal cancer among men (1.067, 0.992-1.148). Lung cancer displayed excess mortality for all types of fuel used, whereas in laryngeal and bladder cancer, the excess was associated with coal-fired industries. There was a risk gradient effect in the proximity of a number of installations.
CONCLUSIONS: Our results could support the hypothesis of an association between risk of lung, laryngeal and bladder cancer mortality and proximity to Spanish combustion installations.