Distribution and isomerization of Hch‐isomers in rats

Blood levels and tissue distribution of alpha‐, beta‐, gamma‐ and delta‐ hexachlorocyclohexane (HCH) were studied following oral administration of alpha‐HCH and gamma‐HCH to rats. There was no evidence of beta‐HCH, gamma‐HCH or delta‐HCH following administration of alpha‐HCH, nor could transformation into alpha‐HCH, beta‐HCH or delta‐HCH be detected after exposure to gamma‐HCH. After 30 days of administration, tissue retention of alpha‐HCH was 5–15 times greater than that of gamma‐HCH. Gamma‐HCH was eliminated to a much greater extent than alpha‐HCH from the tissues, and in particular, from fatty tissue. Alpha‐HCH accumulated in fat and brain, while gamma‐HCH showed very low affinity for lipid. The results attributed the different pharmacokinetic behavior of the isomers to stereoselective reactions in the organism.

Keywords:

• Chlorinated hydrocarbon insecticide
• distribution
• bioaccumulation
• HCH‐isomerization

Notes

Corresponding author.