Cancer incidence in Priolo, Sicily: a spatial approach for estimation of industrial air pollution impact

The territory around the industrial Sicilian area of Priolo, Italy, has been defined as a contaminated site (CS) of national priority for remediation because of diffuse environmental contamination caused by large industrial settlements. The present study investigates the spatial distribution of cancer into the CS territory (period 1999-2006). Different geographical methods used for the evaluation of the impact of industrial air pollutants were adopted. Using the database of Syracuse Province Cancer Registry, gender-specific standardised incidence ratios were calculated for 35 tumour sites for the CS overall and for each municipality included in the CS. A cluster analysis for 17 selected neoplasms was performed at micro-geographical level. The identification of the priority index contaminants (PICs) present in environmental matrices and a review of their carcinogenicity have been performed and applied in the interpretation of the findings. The area has a higher cancer incidence with respect to the provincial population, in particular excess is registered among both genders of lung, bladder and breast cancers as well as skin melanoma and pleural mesothelioma and there is an a priori evidence of association with the exposure to PICs. The study highlights the need to provide different approaches in CSs where several exposure pathways might be relevant for the population. The presence of potential sources of asbestos exposure deserves specific concern.