N‐Ethyl‐2‐pyrrolidone (vapour)
MAK Value Documentation, addendum – Translation of the German version from 2016
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, Geb. 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 the maximum concentration at the work place (MAK value) of N‐ethyl‐2‐pyrrolidone [2687‐91‐4] of 2 ml/m3, considering the endpoints irritation of the respiratory tract and developmental toxicity.
The critical effect of N‐ethyl‐2‐pyrrolidone is degeneration of the olfactory epithelia in rats in a new 13‐week‐inhalation study. Since 2014, the Commission uses an empirical approach to set MAK values for substances with critical effects on the upper respiratory tract or the eyes. According to these proposals, the NOAEC of 62.6 mg/m3 (13.3 ml/m3 vapour) corresponds to a work place air concentration of 31 mg/m3 (6.6 ml/m3). The irritating response in the 13 week study is not more pronounced than after shorter exposition times. Therefore the MAK‐value is increased to 5 ml/m3 for the vapour phase only. Local effects are critical and only minimal irritation occurs at the LOAEC, therefore the assignment of N‐ethyl‐2‐pyrrolidone to Peak Limitation Category I and excursion factor 2 established in 2014 are retained. Also with the increased MAK value, damage to the embryo or foetus is unlikely when the MAK value is observed. Therefore, classification of N‐ethyl‐2‐pyrrolidone in Pregnancy Risk Group C is confirmed.
