Hydrazines 1,1-dimethylhydrazine

This document uses the term "hydrazines" to refer to hydrazine, 1,1-dimethylhydrazine, and 1,2-dimethylhydrazine, collectively. These hydrazines are somewhat similar in chemical structure and reactivity. However, there are some clear differences in their production, uses, and adverse health effects. There are many other hydrazine compounds however, these three hydrazines are discussed together in this document because they are of interest to the U.S. Department of Defense. 

The International Agency for Research on Cancer (lARC) has determined that hydrazine, 1,1-dimethylhydrazine, and 1,2-dimethylhydrazine are possibly carcinogenic to humans (possibly cause cancer in humans). 

The term "hydrazines" is a generic name used in this document to describe a group of three structurally related chemicals hydrazine, 1,1-dimethylhydrazine, and 1,2-dimethylhydrazine. These three hydrazines were selected for inclusion in this document because they have been detected at hazardous waste sites and are of concern to the Department of Defense. Numerous other hydrazine derivatives exist as well. For example, the reader is referred to the Toxicological Profile for 1,2-Diphenylhydrazine (ATSDR 1990) for information on this chemical. 

Ocular Effects. No studies were located regarding ocular effects in humans after dermal exposure to hydrazines. A single application of 3 L of hydrazine, 1,1-dimethylhydrazine, or 1,2-dimethylhydrazine directly to the eyes produced conjunctivitis and erythema of the eyelids in rabbits (Rothberg and Cope 1956). Comeal damage was also noted in rabbits exposed to hydrazine but not in rabbits exposed to... 

Several enzymatic and nonenzymatic pathways are involved in the metabolism of hydrazines. Humans with a slow acetylator genotype may accumulate more hydrazine in the plasma because of an impaired ability to metabolize and excrete the compound (Blair et al. 1985). Although the extent to which each pathway contributes to total metabolism may depend somewhat on the route of exposure (a first-pass metabolic effect for oral exposure, for example), the types of pathways involved and metabolites formed do not appear to be dependent on route. Therefore this section discusses the data without reference to route of exposure. While the metabolic pathways of hydrazine, 1,1-dimethylhydrazine, and... 

Dermal Effects. Contact dermatitis has been observed in humans after dermal exposure to dilute solutions containing hydrazine (Hovding 1967 Suzuki and Ohkido 1979 Wrangsjo and Martensson 1986). Dermal effects (discoloration, irritation) and ocular effects (comeal swelling) were also observed in dogs, rabbits, and guinea pigs after dermal exposure to hydrazine, 1,1-dimethylhydrazine, and... 

TABLE 6-1. Analytical Methods for Determining Hydrazine, 1,1-Dimethylhydrazine,... 

Because of its potential to cause adverse health effects in exposed people, numerous regulations and advisories have been established for hydrazines by various international, national and state agencies. Major regulations and advisories pertaining to hydrazine, 1,1-dimethylhydrazine, and... 

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