3,5-Di-tert-butyl-4-hydroxyphenylpropionsäureoctadecylester [MAK Value Documentation in German language, 2016]

Octadecyl 3‐(3,5‐di‐tert‐butyl‐4‐hydroxyphenyl)propionate The German Commission for the Investigation of Health Hazards of Chemical Compounds in the Work Area has evaluated octadecyl 3‐(3,5‐di‐tert‐butyl‐4‐hydroxyphenyl)propionate to derive a maximum concentration at the workplace (MAK value), considering all toxicity endpoints. Available unpublished study reports and publications are described in detail. Critical effects are induction of metabolizing enzymes in the liver of rats and dogs and the corresponding liver weight increase. In the view of the Commission, an elevation of the total liver cytochrome P450 content of more than 50%, or of the relative liver weight of more than 20%, should be avoided for work place chemicals. In rats, the corresponding NOAEL is 30 mg/kg body weight and day in a 14‐day gavage study. In dogs, a NAEL of 10 mg/kg body weight and day is extrapolated from the LOAEL of 31.5 mg/kg body weight and day in a 90‐day feeding study. The magnitude of these effects does not increase with time. As the irritation potency is low, the oral studies can be used to calculate a MAK value of 20 mg/m3 for the inhalable fraction. As the critical effect is systemic, Peak Limitation Category II is assigned. The default excursion factor of 2 is set as no half‐life in blood is known. In a segment II study in rats, foetal weight is reduced at 500 mg/kg body weight and day with concurrent maternal toxicity. The NOAEL for developmental toxicity in mice is 1000 mg/kg body weight and day. Damage to the embryo or foetus is unlikely when the MAK value is observed and thus, the substance is classified in Pregnancy Risk Group C. Octadecyl 3‐(3,5‐di‐tert‐butyl‐4‐hydroxyphenyl)propionate is not genotoxic or carcinogenic and not a contact sensitizer in humans and guinea pigs. Skin contact is not expected to contribute significantly to systemic toxicity