International Agency for Research on Cancer (IARC) - Summaries & Evaluations


VOL.: 20 (1979) (p. 155)

5. Summary of Data Reported and Evaluation

5.1 Experimental data

Hexachlorobenzene was tested by oral administration in one experiment in mice and in one in hamsters. In mice, it produced liver-cell tumours in animals of both sexes. In hamsters of both sexes, it produced hepatomas, liver haemangiotheliomas and thyroid adenomas. An experiment involving intraperitoneal administration in mice was considered to be inadequate.

Hexachlorobenzene is foetotoxic and produces some teratogenic effects. It was not mutagenic in yeast and did not induce dominant lethal effects in male rats.

5.2 Human data

No case reports or epidemiological studies were available to the Working Group.

The production and use of hexachlorobenzene as a fungicide over the past several decades and its occurrence as a byproduct in the manufacture of other chemicals indicate that widespread human exposure occurs in both the general and working environments. This is confirmed by many reports of its occurrence in the general environment and in human body fluids.

A group of people who were accidentally exposed over a period of time is known to exist; many of these showed toxic manifestations, some lasting for as long as 20 years. No data on carcinogenic effects have been reported.

5.3 Evaluation

There is sufficient evidence that hexachlorobenzene is carcinogenic in mice and hamsters. In the absence of adequate data in humans, it is reasonable, for practical purposes, to regard hexachlorobenzene as if it presented a carcinogenic risk to humans.

For definition of the italicized terms, see Preamble Evaluation.

Subsequent evaluations: Suppl. 7 (1987); Vol. 79 (2001)

Last updated: 31 March 1998

    See Also:
       Toxicological Abbreviations
       Hexachlorobenzene (EHC 195, 1997)
       Hexachlorobenzene (HSG 107, 1998)
       Hexachlorobenzene (ICSC)
       Hexachlorobenzene (PIM 256)
       Hexachlorobenzene (FAO/PL:1969/M/17/1)
       Hexachlorobenzene (WHO Pesticide Residues Series 4)
       Hexachlorobenzene  (IARC Summary & Evaluation, Volume 79, 2001)