Mortality Risk in High Environmental Risk Areas: A Cohort Study in a Southern Italy Municipality

BACKGROUNDThe municipality of Gela is one of the Italian Polluted Sites (IPS) of southern Italy. The main source of environmental contamination comes from a large industrial site which comprises a petrochemical plant and the refining of crude oil. Previous evidence shows that these exposures affect workers and populations health. The study investigates the risk in mortality in a cohort of people residing in Gela to evaluate the effects of individual lifetime exposure. METHODWe retrospectively collected data from the Civil Registry to locate resident individuals over the period 2004–2011 and to ascertain individual duration of exposure. Vital status and mortality by cause were assessed. A Lagrangian dispersion model was carried out to estimate residential exposures to industrial emissions. For residents in Gela, four levels of exposure were defined according to SO2 percentiles:low (<25°pct);medium-low(25°-50°pct); medium-high(50°-75°pct); high(≥75°pct). Resident population in the neighboring municipality of Caltagirone was used as not-exposed area. Cox regression models were performed, adjusted by age, socio-economic status and traffic. RESULTSThe study population includes 88,986 inhabitants of Gela, 41% lived within 2.5km from the site. Results showed higher risk of mortality for total mortality and for ischemic heart disease among women and for all cancers for both genders. For males, in the high exposed area, we observed a significant high mortality risk for bowel cancer (HR=2.53;95%CI:1.42–4.51) and liver cancer (HR=2.01;95%CI:1.20–3.17). Among women we observed an increasing trend in lung cancer mortality risk with increasing levels of exposure (high:HR=2.60;95%CI:1.33–5.12). CONCLUSIONResults confirm previous findings that living in IPS can be an important health risk factor. In Gela, people living in the districts closest to the industrial site have higher mortality for cancers. Environmental remediations and public health interventions are needed