Observations on the progress of chlordane contamination in humans by blood and sebum analysis.

Chlordane residues were determined in human blood and sebum samples. The residue levels in both types of samples were remarkably increased in pest control operators and in the general population living in an area heavily contaminated with chlordane. The compound with the highest level among the residues in the blood of control subjects was oxychlordane followed by trans-nonachlor and trans-chlordane, while in the sebum, the highest levels found was that of trans-chlordane followed by cis-chlordane and trans-nonachlor. The sebum residue was similar to technical chlordane in its component pattern, but it largely originated from sources other than simple exogenous contamination. Thus, sebum might be a unique and available sample source for evaluating direct exposure to technical chlordane. A progressive state of contamination was observed in residents whose homes had been treated with chlordane.