Triphenyl phosphate
MAK Value Documentation, supplement – Translation of the German version from 2021
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 re-evaluated triphenyl phosphate [115-86-6] considering all toxicological end points. Triphenyl phosphate is not neurotoxic in hens and rats and not irritating to the eyes and skin of rabbits. In a 13-week toxicity study with rats, hepatocellular hypertrophy and follicle cell hypertrophy in the thyroid gland started to be not adversely induced at a triphenyl phosphate dose of 105 mg/kg body weight and day. On the basis of the NOEL of 20 mg/kg body weight and day, a maximum concentration at the workplace (MAK value) of 10 ml/m3 has been established. As its critical effect is systemic, triphenyl phosphate has been assigned to Peak Limitation Category II. The default excursion factor of 2 has been set because its half-life is not known. Triphenyl phosphate is not genotoxic in vitro. In vivo genotoxicity tests and lifetime carcinogenicity studies have not been performed with triphenyl phosphate. In a one-generation study in rats, triphenyl phosphate did not induce any effects on the offspring up to 690 mg/kg body weight and day. In a developmental toxicity study in rabbits, an increased proportion of foetuses per litter with absent accessory lung lobes occurred at 200 mg/kg body weight and day. Thus, the NOAEL for developmental toxicity is 80 mg/kg body weight and day. As there is a sufficiently large margin between this NOAEL and the MAK value, triphenyl phosphate has been assigned to Pregnancy Risk Group C. There are no data demonstrating that triphenyl phosphate is sensitizing to the skin or airways or that it penetrates the skin in toxicologically relevant amounts.
