Hydrocarbons, C10-C13, n-alkanes

Carcinogenicity

Description of key information

The available data and available weight of evidence demonstrate that Hydrocarbons, C10 -C13, n-alkanes, <2% aromatics are highly unlikely to be carcinogenic and are not classifiable as carcinogens.  

Key value for chemical safety assessment

Carcinogenicity: via oral route

Endpoint conclusion

Endpoint conclusion:

no study available

Carcinogenicity: via inhalation route

Endpoint conclusion

Endpoint conclusion:

no study available

Carcinogenicity: via dermal route

Endpoint conclusion

Endpoint conclusion:

no study available

Justification for classification or non-classification

These findings do not warrant the classification of Hydrocarbons, C10 -C13, n-alkanes, <2% aromatics as a carcinogen under the Regulation (EC) 1272/2008 on classification, labeling and packaging of substances and mixtures (CLP) or under the Directive 67/518/EEC for dangerous substances and Directive 1999/45/EC for preparations.

Additional information

The available data and available weight of evidence demonstrate that Hydrocarbons, C10 -C13, n-alkanes, <2% aromatics are highly unlikely to be carcinogenic and are not classifiable as carcinogens.

Skin tumor promotion - Evidence of increased tumor promotion was observed in the skin of mice treated with PMA (positive control, 29/30) or with 100% v/v normal paraffin test material (15/30). The skin tumors were predominately of epithelial origin and were papillomas, keratoacanthomas and squamous-cell carcinomas. These tumors were generally well- differentiated with the exception of a few of the squamous-cell carcinomas which were anaplastic with some spindle-cell formations. Early studies that examine structurally analogous test materials, kerosene and jet fuels, were noted to promoter dermal tumors in mice. It was noted that tumor development was associated with moderate to severe skin irritation. Since the materials contain very low or no polycyclic aromatic components (PAC’s), it was suggested that tumor development may have resulted from chronic skin irritation. Therefore, a series of studies were conducted to examine the effect of skin irritation on the tumorigenicity of kerosene. In studies conducted by the American Petroleum Institute (API) and CONCAWE, the absence of skin irritation resulted in no statistically significant differences in tumorigenicity between control animals and animals treated with the test materials (Nessel, Craig S., James J. Freeman, Richard C. Forgash, and Richard H. McKee 1999; CONCAWE 1991)). Accordingly, it was concluded that the tumors were the consequence of repeated dermal irritation and not kerosene or jet fuel per se.

 

Similar findings were noted in the tests of normal paraffins. The tumor promotion activity was greatest in the treated groups displaying the highest degree of dermal irritation, i.e. 100% v/v normal paraffin test material. A low tumor incidence occurred in the groups receiving 50% or 28.6% /v normal paraffin test material (not statistically different from the control group), which correlated to low degrees of dermal irritation. The skin tumor promoting properties of these substances are considered related to repeated dermal irritation (Nessel, 1999).

Hartwig, Greim H, A Reuter, U Richter-Reichhelm HB ,Thielmann HW. Chemically induced pheochromocytomas in rats: mechanisms and relevance for human risk assessment. Crit Rev Toxicol 2009;39(8):695-718.

Nessel, Craig S., James J. Freeman, Richard C. Forgash, and Richard H. McKee. 1999. The Role of Dermal Irritation in the Skin Tumor Promoting Activity of Petroleum Middle Distillates. Toxicological Sciences 49, 48-55 (1999).

Nyska, A., Haseman, J.K., Hailey, J.R., Smetana, S., and Maronpot, R.R. (1999). The association between severe nephropathy and pheochromocytoma in the male F344 rat - the National Toxicology Program experience. Toxicol. Pathol. 27, 456-462.