Human biomonitoring and variation of haematic parameters in a population exposed to PCB and dioxin near a steel plant in the lower Susa Valley

OBJECTIVE: to evaluate the degree of exposure to PCB in a population resident in the lower Susa Valley and its effects on general and endocrine homeostasis. DESIGN, SETTING, PARTICIPANTS AND MAIN OUTCOME MEASURES: in the lower Susa Valley (Piedmont, Italy), there is a steel secondary casting plant (i.e. by fusion of scrap iron), active since the '50s. The emissions of PCB and dioxin coming from the furnace were found in samples of herb, pulse and ground in a preliminary environmental characterisation study. During 2005-2006 we run an epidemiologic study of biomonitoring (measuring as outcome common haematochemical parameters, hormonal parameters, haematic PCB) on a sample of subjects resident in the municipalities with higher levels of PCB and dioxin contamination (exposed subjects), that was compared with another sample (unexposed) of subjects residing in other areas of the Susa Valley. RESULTS: the final sample consisted of 244 subjects (119 unexposed and 125 exposed), balanced by gender, age, education and representative of the Susa Valley population. The greater part of hormonal and toxic parameters showed worse values among exposed than among unexposed, including PCB median value (2.30 μg/l among exposed vs. 1.90 μg/l among unexposed). The difference however was not statistically significant and the values were lower than the population reference values (7.2 μg/l). Haematic PCB values were significantly and positively correlated with age and alcohol consumption and not significantly with male gender. The distribution of the principal haematochemical parameters (hemochrome, total, LDL and HDL cholesterol, triglycerides, glucose, creatinine, bilirubin, transaminases, gamma-glutamiltranspeptidase, proteine electrophoresis) showed also, on the whole, worse values among exposed compared to unexposed, even if the difference was not statistically significant for single values. CONCLUSIONS: the exposed population showed higher values of PCB haematic values and alterations of the hormonal and common heamatochemical parameters compared to unexposed population, even if within reference limits.