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 homes. Samples were collected from homes in the US cornbelt region and analyzed for the concentrations of 11 pesticides and the enantiomer signature of chlordanes. Residues were found for all pesticides analyzed in at least several of the samples, with chlordane dominating in most samples. Racemic residues were seen for the chlordane enantiomers in all samples. Since levels of organochlorine pesticides in urban areas are often an order of magnitude above ambient levels, emissions from house foundations may be a source of these compounds to ambient air. Past research has shown that selective enantiomeric degradation occurs in many environmental samples resulting in non-racemic residues. Knowledge of the enantiomer signatures of chlordane and other pesticides in different media may be useful for distinguishing sources of chlordane to ambient air.