3-chloropropene

Carcinogenicity

Description of key information

Short description of key information:
- Carcinogenicity, oral: Category 2 Suspected human carcinogen, (NCI carcinogenicity study, rat and mouse): NCI 1977

Justification for classification or non-classification

- The results of the 5 conducted experiments on carcinogenicity of 3 -chlororpropene in rodents are diverging. Therefore, following a conservative approach 3 -chloropropene is classified as Category 2 concerning carcinogenicity (H 351: Suspected of causing cancer)

This classification in-line with the classification of IARC ( IARC Monographs on the Evaluation of Carcinogenic Risks to Humans, Volume 71, Re-evaluation of Some Organic Chemicals, Hydrazine and Hydrogen Peroxide, IARC Lyon, France, p. 1236; http://monographs.iarc.fr/ENG/Monographs/PDFs/index.php):

" There is inadequate evidence in humans for the carcinogenicity of allyl chloride.

There is inadequate evidence in experimental animals for the carcinogenicity of allyl chloride."

According to the annex 1 of Directives 67/548/EEC, Index No. 602-029-00-X, 3 -chloropropene is classified as "Carcinogenicity Cat. 3; R40 Limited evidence of a carcinogenic effect" which is also in accordance with the above stated classification (please note the differences between CLP and Directive 67/548/EEC in naming of the carcinogenicity categories, category 2 of CLP is equivalent to category 3 of Directive 67/548/EEC).

Additional information

- 3 -chloropropene was tested for its carcinogenicity in a NCI carcinogenicity study (NCI 1977, 2 years) in rats and mice and in repeated application assays (Van Duuren 1979) in Swiss mice via the skin (> 581 treatments, 94 or 31 mg/mouse) and via subcutaneous injection (549 applications, 1.5 mg/mouse). In the NCI study for mice no final conclusion could be drawn due to the high mortality in males. An increase in the incidence of squamous cell papillomas and carcinomas of the forestomach was reported forboth sexes which was nevertheless statistically not significant. In rats the experiment was completely compromised by the high mortality. In repeated applications to skin or via sc injection no statistical significant increase in tumors. On the contrary in a 2 stage model test (Van Duuren 1979, single skin application + ca. 500 applications of 2.5 µg phorbol myristate acetate) the number of incidences was raised from 6/90 (phorbol myristate acetate controls) to 7/30 in treated mice and the time to tumor was reduced from 449 days to 197 days. In a lung tumor response test in strain A mice ( Theiss 1979, 3 d/wk for 8 wks, i.p. injection), slightly elevated lung tumor response was seen which was significant by only one of the statistical tests used was found in the high dose group (244.9 mg/Kg).