2,2′‑Dichlorodiethyl ether
MAK Value Documentation, addendum – Translation of the German version from 2023
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 Senate Commission for the Investigation of Health Hazards of Chemical Compounds in the Work Area (MAK Commission) has re-evaluated the occupational exposure limit value (maximum concentration at the workplace, MAK value) for 2,2′-dichlorodiethyl ether [111-44-4] considering all toxicological end points. Relevant studies were identified from a literature search. In a study from 1933, 2,2′-dichlorodiethyl ether in concentrations of 100 ml/m3 and above showed irritating effects in humans. At 35 ml/m3 a clearly perceptible unpleasant odour was described and this concentration was irritating in guinea pigs. Reduced body weight gain was observed in rats in a chronic feeding study. This effect was more pronounced in female animals. In a combined repeated dose toxicity study screening also for reproduction/developmental toxicity in rats, the NOAEL for systemic effects was 15 mg/kg body weight and day, the highest dose tested. On this basis, the MAK value has been set at 0.5 ml/m3. As the critical effect of 2,2′-dichlorodiethyl ether is systemic, Peak Limitation Category II has been assigned with an excursion factor of 2. As substances with a higher irritation potency like monochloroacetic acid and 2-chloroethanol have similar or higher MAK values, the MAK value for 2,2′-dichlorodiethyl ether will also protect from irritation. Limited data show no genotoxic or carcinogenic potential for 2,2′-dichlorodiethyl ether. In a screening study, the NOAEL for perinatal toxicity in rats was 15 mg/kg body weight and day. As teratogenicity was not investigated, 2,2′-dichlorodiethyl ether has been assigned to Pregnancy Risk Group D. 2,2′-Dichlorodiethyl ether is not a skin sensitizer in a Local Lymph Node Assay in mice. According to skin absorption models, 2,2′-dichlorodiethyl ether is expected to be taken up via the skin in toxicologically relevant amounts. Therefore, 2,2′-dichlorodiethyl ether remains designated with “H”.
