Disappearance of γ BHC from Avian Liver after Death

Abstract

FROM 1956, the dressing of cereal seeds with organo-chlorine insecticides was responsible for the deaths of many grain feeding birds^1–3 and analyses suggested that the mortality was chiefly caused by dieldrin, aldrin and heptochlor¹. Following these events the Nature Conservancy undertook a nationwide survey of organochlorine residues in wild birds. Nearly all the specimens examined contained detectable amounts of organochlorine insecticides., the more common of which were dieldrin and DDT and its metabolites⁴. Although γ BHC (gamma 1,2,3,4,5,6 hexachlorocyclohexane) has been and is used widely in large quantities⁵, unlike dieldrin, very little was found in the bodies and eggs of predatory birds⁶ or even in the dead bodies of woodpigeons, pheasants and partridges collected at the scene of seed dressing incidents^1,2. Because DDT is known to break down after death in the avian liver⁷, the organ most commonly used for organochlorine analysis, we decided to examine the post-mortem fate of γ BHC in this tissue to see if its previously assumed stability was correct.