Serum levels of organochlorine pesticides in blood donors: A biomonitoring survey in the North of Brazil, 2010-2011.

Data on exposure to organochlorine (OC) pesticides in the Brazilian population are lacking. The purpose of this study was to investigate the distribution of serum levels of OC pesticides in Brazilian blood donors and to determine factors potentially influencing exposure levels. To conduct this biomonitoring survey, blood samples were collected from blood donors attending the Hematherapic Unit in Rio Branco, North of Brazil, in 2010-2011. A total of 1183 (99%) subjects answered to a questionnaire including information on sociodemographics, lifestyle, and dietary habits. Twenty four OC pesticides were measured in serum samples from 978 donors (82%). Associations of OC pesticide serum levels and the number of OCs detected per donor with their potential predictors were explored by logistic and Poisson regression, respectively. Of the 24 OC pesticides analyzed, the highest prevalence was observed for p,p'-dichlorodiphenylethane (p,p'-DDE) (32%), followed by lindane (γ-hexachlorocyclohexane) (20%), heptachlor (16%), and p,p'-dichlorodiphenyltrichloroethane (p,p'-DDT) (13%). 95th percentiles of levels of these four OC pesticides were: 3.85ng/mL (p,p'-DDE) (median<0.09ng/mL), 0.09ng/mL (lindane) (median<0.04ng/mL), 0.23ng/mL (heptachlor) (median<0.09ng/mL), and 0.27ng/mL (p,p'-DDT) (median<0.02ng/mL). Factors significantly associated with a more frequent detection of OC pesticides included age, gender, education, and frequency of fish, manioc flour, açai pulp, and Brazil nuts intake. Major predictors of the number of OC pesticides detected were age, marital status, income, education, and frequency of consumption of manioc flour, açai pulp, and Brazil nuts. For the first time in Brazil, a biomonitoring study has assessed the internal doses of OC pesticides in a large sample of the adult population and potential exposure determinants. Except for lindane, which was permitted for use as a wood preservative until 2007 in Brazil, occurrence of OC pesticides was lower than or in the same range as those observed in other countries.