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

(Group 3)

For definition of Groups, see Preamble Evaluation.

VOL.: 60 (1994) (p. 373)

CAS No.: 25013-15-4
Chem. Abstr. Name: Ethenylmethylbenzene

CAS No.: 611-15-4
Chem. Abstr. Name: 1-Ethenyl-2-methylbenzene

CAS No.: 100-80-1
Chem. Abstr. Name: 1-Ethenyl-3-methylbenzene

CAS No.: 622-97-9
Chem. Abstr. Name: 1-Ethenyl-4-methylbenzene

5. Summary of Data Reported and Evaluation

5.1 Exposure data

Vinyl toluene has been produced since the 1940s, as a mixture mainly of meta and para isomers, by dehydrogenation of meta- and para-ethyl toluene. It is used as a reactive monomer in the production of polymers and coatings. Few data are available on levels of occupational or environmental exposures to vinyl toluene.

5.2 Human carcinogenicity data

No data were available to the Working Group.

5.3 Animal carcinogenicity data

Vinyl toluene (predominantly para isomer) was tested for carcinogenicity in one experiment in mice and one experiment in rats by intragastric intubation. The mixed isomers were tested in one experiment in mice and one experiment in rats exposed by inhalation. No increase in the incidence of tumours was observed in any of the experiments.

5.4 Other relevant data

Vinyl toluene is absorbed in rats exposed by inhalation; its neurotoxicity indicates that it is distributed to the brain in both man and rat. The vinyl moiety is first metabolized to form an epoxide, which is either conjugated with glutathione or further oxidized to a number of products, including carboxylic acids, which are conjugated with glycine. The methyl group can also be oxidized to a carboxylic acid and subsequently conjugated with glycine. Saturation of metabolic pathways in rats commences at a dose of 250 mg/kg bw.

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

Vinyl toluene induces sister chromatid exchange and chromosomal aberrations in cultured human lymphocytes and micronuclei in mouse bone-marrow cells in vivo.

5.5 Evaluation

There is inadequate evidence in humans for the carcinogenicity of vinyl toluene.

There is evidence suggesting lack of carcinogenicity of vinyl toluene in experimental animals.

Overall evaluation

Vinyl toluene is not classifiable as to its carcinogenicity to humans (Group 3).

For definition of the italicized terms, see Preamble Evaluation.

Synonyms for Ethenylmethylbenzene

Synonyms for 1-Ethenyl-2-methylbenzene

Synonyms for 1-Ethenyl-3-methylbenzene

Synonyms for 1-Ethenyl-4-methylbenzene

Last updated 08/26/1997

    See Also:
       Toxicological Abbreviations