Propylenglykoldinitrat
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 maximum concentration at the workplace (MAK value) of propylene glycol dinitrate [6423‐43‐4], considering all toxicological endpoints. A detailed description of the underlying studies is given.
The critical effect in volunteers after an 8‐hour exposure to 0.1 ml/m3 of propylene glycol dinitrate was vasodilation, as indicated by the development of headaches. The effects were very slight. After 4‐hour exposure to 0.2 ml/m3 most of the volunteers developed headaches and changes in visual evoked responses. At 0.03 ml/m3 no effects were observed. In occupational situations it is difficult to assess the levels of exposure to propylene glycol dinitrate that induce symptoms and effects, because of both respiratory tract and skin absorption of vapours. The MAK value for propylene glycol dinitrate has been lowered to 0.01 ml/m3 by analogy with nitroglycerin and ethylene glycol dinitrate because of the same mode of action and the similar NOAEC and LOAEC.
The MAK value also applies to the sum of the concentrations of the three nitrate esters nitroglycerin, ethylene glycol dinitrate and propylene glycol dinitrate in the air. As systemic effects are critical, the assignment to Peak Limitation Category II and the excursion factor of 1, due to the short half‐life, are retained. Although there are no studies on developmental toxicity, propylene glycol dinitrate is assigned to Pregnancy Risk Group C by analogy with nitroglycerin and ethylene glycol dinitrate. No data are available for genotoxicity or carcinogenicity. Skin contact may contribute significantly to systemic toxicity and propylene glycol dinitrate continues to be designated with an “H”. Sensitization is not expected from the limited data.
