Industrial pollution and pleural cancer mortality in Spain

Pleural cancer mortality is an acknowledged indicator of exposure to asbestos and mesothelioma mortality but in 15%-20% of cases no exposure can be recalled. In the past, asbestos was used in many industries and it is still found in many installations. Our objective was to ascertain whether there might be excess pleural cancer mortality among populations residing in the vicinity of Spanish industrial installations that are governed by the Integrated Pollution Prevention and Control (IPPC) Directive and the European Pollutant Release and Transfer Register Regulation and report their emissions to air. An ecological study was designed to examine pleural cancer mortality at a municipal level (8098 Spanish towns) over the period 1997-2006, during which 2146 deaths were registered. We conducted an exploratory "near vs. far" analysis to estimate the relative risks (RRs) of towns situated at a distance of <2 km from installations. This analysis was repeated for each of the 24 industrial groups. RR and their 95% credible intervals (95% CIs) were estimated on the basis of a Poisson conditional autoregressive Bayesian model with explanatory variables. Integrated nested Laplace approximations were used as a Bayesian inference tool. Analysis showed statistically significant RRs in both sexes in the vicinity of 7 of the 24 industrial groups studied (RR, 95% CI), namely, biocide facilities (2.595, 1.459-4.621), ship-building (2.321, 1.379-3.918), glass and mineral fibre production (1.667, 1.041-2.665), non-hazardous waste treatment (1.737, 1.077-2.799), galvanising (1.637, 1.139-2.347), organic chemical plants (1.386, 1.075-1.782) and the food and beverage sector (1.255, 1.006-1.562). In the proximity of sources pertaining to the biocide, organic chemical and galvanising sectors, the risk was seen to be rising among men and women, a finding that could indicate airborne environmental exposure. These results support that residing in the vicinity of IPPC-registered industries that release pollutants to the air constitutes a risk factor for pleural cancer.