Glycerintrinitrat
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 work place (MAK value) and the Pregnancy Risk Group of nitroglycerin [55‐63‐0].
The critical effect in volunteers after a 25‐minute exposure to 0.05 ml/m3 of a mixture of ethylene glycol dinitrate and nitroglycerin was vasodilation, as indicated by the development of headaches or decreases in blood pressure. In workers, headaches were reported at nitroglycerin concentrations of 0.03 to 0.11 ml/m3 with a NOAEC below 0.01 ml/m3 nitroglycerin. Based on this data, the MAK value for nitroglycerin was established at 0.01 ml/m3. As the MAK value is derived from experiences in workers, the increased respiratory volume at the work place is considered.
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.
In rats, the NOAEL for developmental toxicity after oral application is 86 mg/kg body weight and day. After toxicokinetic scaling this dose corresponds to a concentration of 16 ml/m3 at the work place. The difference of this concentration to the MAK value is sufficient, therefore, nitroglycerin remains assigned to Pregnancy Risk Group C.
Skin contact may contribute significantly to systemic toxicity and nitroglycerin continues to be designated with an “H”. Sensitization is not expected from the limited data.
