2‐Propoxyethanol (2‐(Propyloxy)ethanol)
MAK Value Documentation, addendum – 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 re‐evaluated 2‐(propyloxy)ethanol (2‐propoxyethanol) [2807‐30‐9] considering all toxicological end points.
2‐(Propyloxy)ethanol is a haemolytic and irritant glycol ether, similar to the homologous 2‐butoxyethanol. The haemolytic activity for both compounds is mediated by the corresponding alkoxy acid and is lower in human erythrocytes than in rat erythrocytes in vitro. The critical effect is the irritation seen in subchronic studies in rats at the lowest concentration tested of 100 ml/m3. A NOAEC was not obtained. For 2‐butoxyethanol the NOAEC for nasal effects in rats was 31 ml/m3. Therefore, by analogy with the better investigated 2‐butoxyethanol, the maximum concentration at the workplace (MAK value) of 2‐(propyloxy)ethanol is lowered to 10 ml/m3. This limit also protects from systemic toxicity. The assignment to Peak Limitation Category I with an excursion factor of 2 is retained.
A prenatal toxicity study in rats was re‐evaluated by the Commission and the NOAEC for developmental toxicity of 400 ml/m3 was confirmed. In rabbits, the NOAEC for developmental toxicity is 500 ml/m3. Even after considering the increased respiratory volume at the workplace the differences of both NOAECs to the MAK value are sufficient. Therefore, damage to the embryo or foetus is unlikely when the MAK value is observed and 2‐(propyloxy)ethanol remains assigned to Pregnancy Risk Group C.
2‐(Propyloxy)ethanol is not genotoxic in vitro. In vivo studies as well as carcinogenicity studies are not available.
Percutaneous absorption can contribute significantly to systemic toxicity and 2‐(propyloxy)ethanol remains designated with an “H” notation. Results in animal studies do not point to a sensitization potential.
