Rapid elimination of pentachloronitrobenzene and metabolite from sheep fat

Abstract

Sheep were dosed orally with pentachloronitrobenzene (PCNB) (31–32 mg/kg body weight), either as a purified crystalline chemical (⪖ 99%) or a commercial 75% w/w wettable powder (w.p.). About 80% of the dose of pure PCNB was eliminated via the faeces in the 3 days after dosing and about 5% was present as pentachloroaniline (PCA). About 0.4% was excreted in the urine, predominantly as PCA. Traces of PCNB appeared for a short time in omental fat. The highest residues in fat were of PCA (2–8 ppm maximum). These appeared 1 and 3 days after dosing sheep with the wettable powder and the crystalline chemical respectively. The biological half-life of PCA in fat varied between 1–3 days. The most persistent residue was hexachlorobenzene (HCB) which occurs as an impurity in commercial PCNB.