Abstract
Summary. Chronic feeding of hexachlorobenzene to rats increases the levels of certain hepatic haemoproteins prior to the onset of hepatic porphyria. The onset of hepatic porphyria is slow and only water soluble porphyrins accumulate in the livers. The accumulation of hexachlorobenzene by the liver is progressive but no direct correlation exists between the amount of HCB in the liver, the extent of hepatic porphyria and the changes in haemoprotein concentration. Similarities between experimental hepatic porphyria induced by hexachlorobenzene and those seen in human symptomatic porphyria are presented and emphasize the usefulness of the hexachlorobenzene model with which to study the human disease.