Organochlorine pesticide concentrations and enantiomer fractions for chlordane in indoor air from the US cornbelt

Thirty-seven indoor air samples were collected and analyzed to determine if enantioselective degradation of past-use organochlorine pesticides, occurs indoors and to increase the available information on concentrations in hom es. Samples were collected from homes in the US cornbelt region and analyze d for the concentrations of 11 pesticides and the enantiomer signature of c hlordanes. Residues were found for all pesticides analyzed in at least seve ral of the samples, with chlordane dominating in most samples. Racemic resi dues were seen for the chlordane enantiomers in all samples. Since levels o f organochlorine pesticides in urban areas are often an order of magnitude above ambient levels, emissions from house foundations may be a source of t hese compounds to ambient air. Past research has shown that selective enant iomeric degradation occurs in many environmental samples resulting in non-r acemic residues. Knowledge of the enantiomer signatures of chlordane and ot her pesticides in different media may be useful for distinguishing sources of chlordane to ambient air. Published by Elsevier Science Ltd.