Relative concentrations of organochlorines in adipose tissue and serum among reproductive age women

Abstract

Much of the available literature focusing on organochlorine exposure and human health effects has relied upon serum for quantifying exposure despite adipose tissue being the purported "gold standard". The accuracy of exposure status is dependent upon serum being a valid and reliable proxy for adipose tissue regardless of compound under study and served as the impetus for study. Serum and omentum fat concentrations for 62 polychlorinated biphenyls (PCBs) and 7 organochlorine pesticides (OCPs) were determined using gas chromatography with electron capture and compared to assess their relative abundance and correlation among 15 women aged 18-40 years undergoing laparoscopy. The relation between concentration in serum and fat was determined by linear regression. Of the 20 organochlorines (OCs) (29%) present in both serum and fat samples, moderate linear correlations (r > 0.6) were observed between lipid-adjusted serum and fat concentrations for PCBs #138, 153, 180, 188, 194, 206, and DDE. Forty-nine OCs were present in adipose samples but measured below the LOD in serum samples. Our findings underscore the potential for discrepant human health results associated with OC exposure on the basis of medium used for quantification purposes, especially for less ubiquitous compounds or when study samples include individuals with relatively low exposures. These data support earlier findings and argue for concerted methodological work aimed at developing standardized laboratory methods for epidemiologic studies.