2021/12/30 by Hartwig, Andrea, MAK Commission
#1 #1-Dimethylhydrazin #1-dimethylhydrazine #DNA methylation #DNA-Methylierung #Kanzerogenität #Keimzellmutagenität #N #N-Dimethylhydrazin #N-dimethylhydrazine #Toxizität #carcinogenicity #germ cell mutagenicity #toxicity #unsymmetrical dimethylhydrazine #unsymmetrisches Dimethylhydrazin
paper · doi:10.34865/mb5714d6_4ad
The German Commission for the Investigation of Health Hazards of Chemical Compounds in the Work Area has re-evaluated 1,1-dimethylhydrazine [51-14-7] considering all toxicological end points. The acute toxicity of 1,1-dimethylhydrazine is caused by depletion of gamma-aminobutyric acid leading to the effects on the central nervous system. During chronic and subchronic exposure, adverse effects on the blood, liver, nervous system, colon and spleen were observed in dogs and adverse effects on the liver and colon were observed in rats. In mice, the substance causes toxicological effects on the nose, lungs and gall bladder. In carcinogenicity studies, inhaled 1,1-dimethylhydrazine caused tumours in the lungs, pituitary gland and pancreas in rats in addition to thyroid carcinomas, haemangiosarcomas and Kupffer cell sarcomas in mice. In carcinogenicity studies using ultra-pure 1,1-dimethylhydrazine, a number of tumours formed in mice, including in the lungs, liver, blood vessels and the nasal mucosa. Orally applied, it caused tumours in the liver and pituitary gland of rats, in the blood vessels, lungs and kidneys in mice and in the blood vessels and colon of hamsters. On the basis of these effects, 1,1-dimethylhydrazine remains classified in Carcinogen Category 2. No maximum concentration at the workplace (MAK value) can be derived. The substance is clastogenic and mutagenic in bacteria and soma cells in vitro and clastogenic in several organs after exposure in vivo. On the basis of these effects and its ability to inhibit DNA synthesis in mouse testes after oral application, 1,1-dimethylhydrazine has been classified in Germ Cell Category 3 A. 1,1-Dimethylhydrazine is irritating to the skin of dogs, guinea pigs and rabbits and to the eyes of rabbits. Due to the low LD 50 values determined in animals after dermal application and potential genotoxic effects after dermal application, the “H” designation (for substances for which skin contact contributes to systemic toxicity) has been retained. Although no studies considering the sensitizing potential are available, the “Sh” (for substances which cause sensitization of the skin) has been retained due to its structural similarity to the known contact allergen hydrazine.