Mineral oils (petroleum), severely refined
MAK Value Documentation – Translation of the German version from 2018
Andrea Hartwig1 (Chair of the Permanent Senate Commission for the Investigation of Health Hazards of Chemical Compounds in the Work Area, Deutsche Forschungsgemeinschaft)MAK Commission2
1 Institute of Applied Biosciences, Department of Food Chemistry and Toxicology, Karlsruhe Institute of Technology (KIT), Adenauerring 20a, Building 50.41, 76131 Karlsruhe, Germany
2 Permanent Senate Commission for the Investigation of Health Hazards of Chemical Compounds in the Work Area, Deutsche Forschungsgemeinschaft, Kennedyallee 40, 53175 Bonn, Germany
Abstract
The German Commission for the Investigation of Health Hazards of Chemical Compounds in the Work Area has evaluated 4 severely refined mineral oils [92062‐35‐6, 72623‐83‐7, 92045‐45‐9, 92045‐44‐8] considering all toxicological endpoints.
These mineral oils are severely refined to eliminate olefins and carcinogenic polycyclic aromatic hydrocarbons. The critical effect is lung toxicity which is observed as microgranulomas in two long‐term studies with rats and dogs at a respirable aerosol concentration of 100 mg/m3 with a NOAEC of 5 mg/m3. A MAK value of 5 mg/m3 has been set as the respirable fraction (R). Severely refined mineral oils have been assigned to Peak Limitation Category II, because the lung effects are due to a cumulative overload and an excursion factor of 4 has been set. Severely refined mineral oils are not genotoxic and not carcinogenic after oral, dermal or subcutaneous application to rats and mice.
Developmental toxicity studies with a white mineral oil show a NOAEC of 1000 mg/m3 and a NOAEL of 5000 mg/kg body weight in rats. After toxicokinetic scaling, the differences of the resulting respective concentrations at the workplace to the MAK value are sufficient. Therefore, damage to the embryo or foetus is unlikely when the MAK value is observed and severely refined mineral oils are assigned to Pregnancy Risk Group C.
Skin absorption is very limited and does not contribute to systemic toxicity. Severely refined mineral oils are not regarded as skin or respiratory sensitizers.
