Porphyria Cutanea Tarda and Agricultural Pesticides

Abstract

Some cases of porphyria cutanea tarda have been associated with the ttse of the organochlorine insecticide lindane and the organophosphorous insecticide diazinon. In the case of diazinon, an impurity is the active agent. This impurity has been identified as an isomer of diazinon and is designated isodiazinon. In rats treated with diazinon and isodiazirion, increased faecal excretion of porphyrins was seen only in animals treated with both compounds. In these animals the enzyme ferrochelatase was significantly inhibited. It is suggested that porphyria cutanea tarda only arises on exposure to these agents in persons with a pre-existing deficiency of uroporphyrinogen decarboxylase.

The Regulatory Evaluation of the Skin Effects of Pesticides

“…A case report from Australia identified an isomer of diazinon as a cause of porphyria cutanea tarda (Collins et al, 1982).…”

Effects of polyhalogenated aromatic compounds on porphyrin metabolism.

“…In Czechoslovakia, workers from a 2,4,5-T production plant became ill from exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) (17). At the initial investigation, 20% had PCT and another 21% had uroporphyrinuria, but 10 years later these signs and symptoms were rare, Isolated cases of PCT and porphyrinuria from methyl chloride and lindane have also been reported (18)(19)(20). Polychlorinated biphenyls (PCBs), PBBs, and vinyl chloride have been reported to produce subelinical CHP (21-23).…”