Methyl phenyl sulphide

Endpoint summary

Key value for chemical safety assessment

Skin sensitisation

Endpoint conclusion

Endpoint conclusion:

adverse effect observed (sensitising)

Additional information:

In a study conducted by Beerens-Heijnen (2010), the test substance, Thioanisole, was examined for its ability to cause skin sensitization when applied to female CBA/J strain of mice in a Local Lymph Node Assay. The test substance was applied to the dorsal surface of the ear of each rabbit for three consecutive days at concentrations of 10, 25 and 50% (w/w). On day 6 of experimentation, the auricular lymph nodes were excised and pooled for each animal. After precipitating the DNA of the lymph node cells, radioactivity measurements were made and results expressed as the number of Disintegrations per Minute (DPM). A Stimulation Index (SI) was calculated for each group. The mean DPM/animals values for the experimental groups treated with the test substance concentrations of 10, 25 and 50% were 693, 1508 and 3275 DPM respectively. The mean DPM value for the control group was 662. The Stimulation Index values calculated for the substance concentrations 10, 25 and 50% were 1, 2.3 and 4.9 respectively. Slight irritation of the ears was shown by all experimental animals at all three concentrations. However, this was not considered to have a toxicologically significant effect on the activity of the nodes. No oedema was observed in any of the animals examined. All auricular lymph nodes of the animals at 50% concentration were considered increased in size. All other auricular lymph nodes were considered normal in size. No macroscopic abnormalities of the surrounding area were noted in any of the animals. Body weights and body weight gain of experimental animals remained in the same range as the controls over the study period. The slight body weight loss in some animals was not considered toxicologically significant. No mortality occurred and no symptoms of systemic toxicity were observed in the animals of the main study. Under the conditions of this study, the test substance, Thioanisole, should be considered to be a skin sensitiser. Based on these results, the test substance should be classified as a Category 1 skin sensitizer and have the hazard statement H317: May casue an allergic reaction associated with it, in accordance with Regulation EC No. 1272/2008. According to Directive 67/548/EEC, the test substance should be classified with the risk phrase R43: May cause sensitization by skin contact and have the symbol Xi, Irritant associated with it.

Migrated from Short description of key information:
A single key study is available. The study was conducted according to the Local Lymph Node Assay and was conducted on female mice of the CBA/J strain. A Stimulation Index (SI) was calculated for each group. The mean DPM/animals values for the experimental groups treated with the test substance concentrations of 10, 25 and 50% were 693, 1508 and 3275 DPM respectively. The mean DPM value for the control group was 662. The Stimulation Index values calculated for the substance concentrations 10, 25 and 50% were 1, 2.3 and 4.9 respectively. The calculated EC3 value was circa 31.

Justification for classification or non-classification

Based on the results of the skin sensitisation study, the test substance should be classified as a Category 1 skin sensitizer and have the hazard statement H317: May casue an allergic reaction associated with it, in accordance with Regulation EC No. 1272/2008. According to Directive 67/548/EEC, the test substance should be classified with the risk phrase R43: May cause sensitization by skin contact and have the symbol Xi, Irritant associated with it.