Butylated hydroxytoluene (BHT) – Evaluation of a BAR
Assessment Values in Biological Material – Translation of the German version from 2023
Gabriele Leng1Hans Drexler2 (Head of the working group “Assessment Values in Biological Material” of the Permanent Senate Commission for the Investigation of Health Hazards of Chemical Compounds in the Work Area, Deutsche Forschungsgemeinschaft)
Andrea Hartwig3 (Chair of the Permanent Senate Commission for the Investigation of Health Hazards of Chemical Compounds in the Work Area, Deutsche Forschungsgemeinschaft)
MAK Commission4
1 Currenta GmbH & Co. OHG, CUR-SEL-SER-GS-BLM-Institut für Biomonitoring, 51368 Leverkusen, Germany
2 Friedrich-Alexander-Universität Erlangen-Nürnberg, Institute and Outpatient Clinic of Occupational, Social, and Environmental Medicine, Henkestraße 9–11, 91054 Erlangen, Germany
3 Institute of Applied Biosciences, Department of Food Chemistry and Toxicology, Karlsruhe Institute of Technology (KIT), Adenauerring 20a, Building 50.41, 76131 Karlsruhe, Germany
4 Permanent Senate Commission for the Investigation of Health Hazards of Chemical Compounds in the Work Area, Deutsche Forschungsgemeinschaft, Kennedyallee 40, 53175 Bonn, Germany
Abstract
In 2012, the German Commission for the Investigation of Health Hazards of Chemical Compounds in the Work Area derived a maximum workplace concentration (MAK value) for butylated hydroxytoluene (BHT) [128-37-0] of 10 mg/m3 (inhalable fraction). Measuring body burden after exposure to BHT showed BHT acid (3,5-di-tert-butyl-4-hydroxybenzoic acid) in urine to be an adequate biomarker. To date, no data have been published on urinary concentrations of BHT acid after occupational exposure to BHT with correlation to air concentrations of BHT or with effects from BHT exposure; as a result, no biological tolerance value (BAT value) can be derived. There are, however, data available for the derivation of a biological reference value (BAR). Based on the available data, a BAR of 7 µg BHT acid (after hydrolysis)/l urine has been established. Sampling time is at the end of exposure or the end of the shift.
