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


VOL.: 31 (1983) (p. 163)

5. Summary of Data Reported and Evaluation

5.1 Experimental data

Gyromitrin was tested for carcinogenicity in one experiment in mice by gavage, producing increased incidences of lung, forestomach and clitoral gland tumours in females and of preputial tumours in males. N-Methyl-N-formylhydrazine, a metabolite, was tested in mice by administration in the drinking-water, increasing the incidence of tumours of the liver, lung, gall bladder and bile duct. N-Methylhydrazine, another metabolite, was tested in mice and hamsters by administration in the drinking-water; it produced increased incidences of histiocytomas and caecal tumours in hamsters.

Gyromitrin was not mutagenic in bacteria, but the metabolite N-methylhydrazine gave positive results. The data were inadequate to evaluate the activity of gyromitrin in short-term tests.

No data were available to evaluate the teratogenicity of this compound to experimental animals.

5.2 Human data

Gyromitrin is a natural substance found in the false morel. Although most of the compound is destroyed by proper preparation before eating, there is still a possibility for human exposure.

No data were available to assess the teratogenicity or chromosomal effects of this compound in humans.

No case report or epidemiological study of the carcinogenicity of gyromitrin was available to the Working Group.

5.3 Evaluation

Results of studies on gyromitrin itself, supported by studies on two of its metabolites, provide sufficient evidence for the carcinogenicity of gyromitrin in experimental animals. No data on humans were available.

For definition of the italicized terms, see Preamble Evaluation.

Subsequent evaluation: Suppl. 7 (1987)

Last updated: 16 April 1998

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