Hydrocarbons, C16-C22, n-alkanes, isoalkanes, <2% aromatics

Endpoint summary

Key value for chemical safety assessment

Skin sensitisation

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not sensitising)

Additional information:

No sensitisation studies are available for the registration substance itself. However, reliable data are available for a number of related Fischer-Tropsch process-derived substances in the relevant carbon number range. These are used as weight of evidence.

In a guinea pig maximisation test, conducted in accordance with OECD 406 and GLP (Huygevoort, 2014a), Hydrocarbons, C18-C24, isoalkanes, <2% aromatics was tested at a challenge concentration of 50% v/v in corn oil. Intradermal induction was performed at a concentration of 50% v/v, and topical induction used undiluted test substance. No skin reactions were observed in any test or control group animals at challenge indicating that the substance is not sensitising to skin.

In a guinea pig maximisation test, conducted in accordance with OECD 406 and GLP (van Huygevoort, 2014b), Hydrocarbons, C12-C15, n-alkanes, isoalkanes, <2% aromatics was tested at a challenge concentration of 20% v/v in corn oil. Intradermal induction was performed at a concentration of 20% v/v, and topical induction used undiluted test substance. No skin reactions were observed in any test or control group animals at challenge indicating that the substance is not sensitising to skin.

 

In a guinea pig maximisation test, conducted in accordance with OECD 406 and GLP, limited range GTL Kerosine (C8-C12) was tested at challenge concentrations of 50% v/v and 10% v/v in paraffin oil (Huntingdon Life Sciences, 1997e). Intradermal induction was performed at a concentration of 50% v/v, and topical induction used undiluted test substance.

Challenge application of 50% v/v gave rise to eschar formation or oedema in six test and five control animals, moderate erythema in one test animal and slight erythema in test and six control animals. Exfoliation was evident in seventeen test and nineteen control animals.

Challenge application of 10% v/v caused eschar formation in two test and no control animals; a further seven test and two control animals showed slight erythema. Exfoliation was evident in twelve test and sixteen control animals.

Challenge application of paraffin oil alone gave rise to slight erythema in two control animals. Exfoliation was evident in 13 test and 14 control animals.

Abrasions were evident in the majority of test animals after the second (topical) induction; the control animals remained in overt good health. One test group animal was found dead on Day 2; necropsy revealed incomplete collapse of the lungs. There were no clinical observations and no effects on overall bodyweight gains.

A significant dermal response (a reaction more marked than the most severe evident amongst the control animals) was observed in no test animal following challenge with 50% v/v GTL Kerosine in paraffin oil, and in 2/20 test animals following challenge application of 10% v/v GTL Kerosine in paraffin oil.

Under the conditions of the test, limited range GTL Kerosine was therefore not sensitising.

In a guinea pig maximisation test conducted according to OECD 406 and GLP, Paraffin Waxes (Fischer-Tropsch), light, C15-27, branched and linear (GTL Paraffin Waxes, C15-27) was tested at challenge concentrations of 100% and 50% in liquid paraffin. At the 100% challenge concentration, slight erythema was observed in 3/11 test group animals and 1/5 control group animals at the 24-hour observation. All skin reaction had fully resolved at the 48-hour observation. No skin reactions were observed in any test or control group animals at the 50% challenge concentration.

Under the conditions of the test, GTL Paraffin Waxes (C15-27) was therefore not sensitising.

In a guinea pig maximisation test, conducted in accordance with OECD 406 and GLP, GTL Base Oil Distillates (C18-C50 – branched, cyclic and linear) was tested at challenge concentrations of 100% and 50% in liquid paraffin (Richeux, 2008).

Intradermal induction was performed at a concentration of 100%, and topical induction used undiluted test substance also. Under the conditions of the test, the test material produced a 0% sensitisation rate and was found not sensitising to guinea pig skin.

 

Migrated from Short description of key information:
Guideline skin sensitisation studies are available for several Fischer-Tropsch process-derived substances in the entire carbon number range relevant for Hydrocarbons, C16-C22, n-alkanes, isoalkanes, <2% aromatics. None of the tested substances showed any evidence of skin sensitising potential. It is therefore appropriate to use the available information as weight of evidence to demonstrate that the constituents of the registration substance are not sensitising and no classification is required for this endpoint.

Respiratory sensitisation

Endpoint conclusion

Additional information:

Migrated from Short description of key information:
No sensitisation studies are available for Hydrocarbons, C18-C24, isoalkanes, <2% aromatics itself. However reliable studies are available for a number of related substances covering the relevant range of carbon numbers, all of which indicate that the constituents present in Hydrocarbons, C18-C24, isoalkanes, <2% aromatics are not sensitising. Based on the available weight of evidence it can therefore be concluded that Hydrocarbons, C18-C24, isoalkanes, <2% aromatics is not a skin sensitiser.

Justification for classification or non-classification

Based on the available read-across in vivo skin sensitisation data, Hydrocarbons, C16-C22, n-alkanes, isoalkanes, <2% aromatics does not require classification as a skin sensitiser according to the criteria of Regulation (EC) No. 1272/2008.