2‐Butoxyethanol
MAK-Begründung, Nachtrag
Andrea Hartwig1 (Vorsitz der Ständigen Senatskommission zur Prüfung gesundheitsschädlicher Arbeitsstoffe, Deutsche Forschungsgemeinschaft)MAK Commission2
1 Institut für Angewandte Biowissenschaften, Abteilung Lebensmittelchemie und Toxikologie, Karlsruher Institut für Technologie (KIT), Adenauerring 20a, Geb. 50.41, 76131 Karlsruhe, Deutschland
2 Ständige Senatskommission zur Prüfung gesundheitsschädlicher Arbeitsstoffe, Deutsche Forschungsgemeinschaft, Kennedyallee 40, 53175 Bonn, Deutschland
Abstract
The German Commission for the Investigation of Health Hazards of Chemical Compounds in the Work Area has re‐evaluated the carcinogenicity classification of 2‐butoxyethanol [111‐76‐2]. In long‐term studies, 2‐butoxyethanol resulted in hepatocellular carcinomas, haemangiosarcomas and forestomach tumours in mice and phaeochromocytomas in rats and was classified in Carcinogen Category 4.
New studies indicate that the hepatic tumours and the phaeochromocytomas are consequences of the haemolysis which is caused by the metabolite butoxyacetic acid. The forestomach tumours in mice are judged to be irrelevant for humans. There are differences between rats and humans concerning the formation and the haemolytic potency of butoxyacetic acid, which renders humans much less susceptible for haemolysis than rats, although humans can develop signs of haemolysis after severe oral intoxication. However, the CNS‐depression and the irritation caused by 2‐butoxyethanol precludes that humans are exposed regularly to 2‐butoxyethanol concentrations at the workplace which might result in significant haemolysis. Therefore, the Commission has removed 2‐butoxyethanol from the Carcinogen Category 4.
