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

(Group 2A)

For definition of Groups, see Preamble Evaluation.

VOL.: 53 (1991) (p. 353)

CAS No.: 2425-06-1

Chem. Abstr. Name: 3a,4,7,7a-Tetrahydro-2-[(1,1,2,2-tetrachloroethyl)thiol]-1H-isoindole-1,3-(2H)dione

5. Summary of Data Reported and Evaluation

5.1 Exposure data

Captafol is a fungicide that has been widely used since 1961 for the control of fungal diseases in fruits, vegetables and some other plants.

It has been formulated for use as dusts, emulsifiable concentrates, flowable suspensions and water-dispersible granules, and also in combination with other pesticides.

Exposure can occur during its production and application and, at much lower levels, from consumption of foods containing residues.

5.2 Carcinogenicity in humans

No data were available to the Working Group.

5.3 Carcinogenicity in experimental animals

Captafol was tested for carcinogenicity in one study in mice and in two studies in rats by oral administration. In mice, it produced a high incidence of adenocarcinomas of the small intestine and of vascular tumours of the heart and spleen; the increase in tumours of the heart was dose-related for animals of each sex. Increases in the incidence of hepatocellular carcinomas were also observed in animals of each sex. In two studies in rats, captafol produced a dose-related increase in the incidence of renal carcinomas in males; in one of these, it also induced dose-related increases in the incidence of benign renal tumours in females and of liver tumours in males and females.

5.4 Other relevant data

In one study, captafol increased the frequency of enzyme-positive foci in rat liver.

Captafol did not affect embryonic development in rabbits or monkeys but was embryolethal and teratogenic at high doses in hamsters.

No data were available on the genetic and related effects of captafol in humans.

Administration of captafol induced dominant lethal effects in rats. Captafol induced positive results in various short-term tests in human and mammalian cells in vitro, including gene mutation and chromosomal aberrations. It induced DNA damage and gene mutation in fungi and bacteria.

5.5 Evaluation

No data were available from studies in humans.

There is sufficient evidence in experimental animals for the carcinogenicity of captafol.

In making the overall evaluation, the Working Group took into consideration the following supporting evidence: Captafol is active in a wide range of tests for genetic and related effects, including the generally insensitive in-vivo assay for dominant lethal mutation.

Overall evaluation

Captafol is probably carcinogenic to humans (Group 2A).

For definition of the italicized terms, see Preamble Evaluation.


Last updated: 21 November 1997

    See Also:
       Toxicological Abbreviations
       Captafol (HSG 49, 1990)
       Captafol (ICSC)
       Captafol (PIM 097)
       Captafol (FAO/PL:1969/M/17/1)
       Captafol (WHO Pesticide Residues Series 3)
       Captafol (WHO Pesticide Residues Series 4)
       Captafol (Pesticide residues in food: 1976 evaluations)
       Captafol (Pesticide residues in food: 1977 evaluations)