Mortality and cancer incidence in a population exposed to TCDD after the Seveso, Italy, accident (1976-2013).

OBJECTIVES:The Seveso accident (1976) caused the contamination with 2,3,7,8-tetrachlorodibenzo-para-dioxin (TCDD) in an area north of Milan, Italy. We report the results of the update of mortality and cancer incidence in the exposed population through 2013. METHODS:The study cohort includes subjects living in three contaminated zones with decreasing TCDD soil concentrations (zone A, B and R) and in a surrounding uncontaminated territory (reference). Poisson models stratified/adjusted for gender, age and period were fitted to calculate rate ratios (RRs) and 95% CIs. RESULTS:In zone A in males, we found elevated mortality from circulatory diseases in the first decade after the accident (17 deaths, RR 2.00, 95% CI 1.24 to 3.23). In females, mortality from diabetes mellitus was increased, with a positive trend across zones. Incidence of soft tissue sarcoma was increased in males in zone R in the first decade (6 cases, RR 2.62, 95% CI 1.01 to 6.83). In females in zone B, there was an excess of non-Hodgkin's lymphoma after 30 years (6 cases, RR 2.87, 95% CI 1.14 to 7.23). Multiple myeloma was increased in the second decade in females in zone B (4 cases, RR 5.09, 95% CI 1.82 to 14.2) and in males in zone R (11 cases, RR 2.15, 95% CI 1.08 to 4.26). In males in zone R, there was a leukaemia excess after 30 years (23 cases, RR 2.02, 95% CI 1.04 to 3.93). CONCLUSIONS:Although with different patterns across gender, zone and time, we confirmed previous results of increased cardiovascular diseases, diabetes, soft tissue sarcoma, and lymphatic and haematopoietic cancers.