POSSIBLE RISK OF ENDOMETRIOSIS FOR SEVESO, ITALY, RESIDENTS - AN ASSESSMENT OF EXPOSURE TO DIOXIN

A recent study by Rier et al. showed that rhesus monkeys exposed daily for 4 years to 5 or 25 ppt of dioxin in food develop endometriosis, w ith incidence and severity related to dose. We aimed to determine whet her the total time-integrated dioxin exposure of a human population co uld be comparable to that of Rier's monkeys. We selected a sample of r esidents of Seveso, Italy, who were acutely exposed to high levels of dioxin following an accident in 1976. We conducted a toxicokinetic ana lysis which takes into account species and exposure differences in dos e and timing between humans and monkeys. The area under the time-conce ntration curve for dioxin in fat, which corresponds to cumulative expo sure over time, ranges for some of the most heavily exposed Seveso res idents from approximately 1.7 x 10(6) ppt-days to 1.1 x 10(8) ppt-days . These values exceed in all cases the values for the monkeys exposed to 25 ppt or 5 ppt. Given their exposure, the Seveso population should be an ideal epidemiologic cohort to rule out or confirm whether expos ure to dioxin leads to an increased risk of endometriosis in humans.