Nitrosamine worker exposure

Miscellaneous. Volatile nitrosamines can escape into the atmosphere from a variety of other sources. Automobile and diesel engine exhausts may contain N-nitroso compounds, including NDMA at trace levels (5). Nitrosodiethanolamine (NDEIA) is a likely air contaminant in machine shops which use cutting and grinding fluids contaminated with high concentrations of NDElA (10). Several herbicides, known to contain appreciable levels of volatile nitrosamines (9), are applied as aqueous sprays it is likely that worker exposure via inhalation may be appreciable. 

With regard to worker exposure to nitrosamines present in agricultural chemicals, the volatile nature of these materials suggests inhalation and dermal contact as the major routes of absorption. There is a potential hazard of exposure to field applicators, especially commercial farmers and growers who regularly spray their crops and land. Manufacturers of the formulations may have workers who are exposed to unusually... 

Adverse effects associated with multiple chemical exposures associated with rocket testing at a commercial defense test facility. This study evaluated the excess mortality of workers employed at a rocket test site over a period beginning in the 1950s. Excess lung cancer was identified in this cohort of workers and their health outcomes were possibly associated with exposure to hydrazines, nitrosamines, asbestos, trichloroethylene, and other chemicals. 

A-nitrosodimethylamine (NDMA). A-Nitrosomorpholine (NMOR) is also produced in this process, but the origin of this pollutant is unknown. Samples collected from different tanneries showed airborne nitrosamine contamination ranging from 0.05-47 Xg/m3 NDMA (mean 3.4 pg/m3) and 0.05-2.0 pg/m3 NMOR (mean 0.2 pg/m3)64. Studies have indicated the possible risk of nasal cancer to workers exposed to NDMA at a daily exposure level of 440 pg NDMA/person/day and 20 pg NMOR/person/day65. Animals exposed to long-term inhalation of NDMA were found to have formed malignant tumours of mainly the liver and kidney66. 

Despite the epidemiological pitfalls, the nitrosamine levels found in this study are highly significant. Initially, NIOSH found the worst case exposures were typically among the feed mill and calendering operators one worker had a time-weighted average NMOR exposure of 25 yg/M3, an NDMA exposure of 0.37 9/ 3, and an NPYR exposure of 0.78 yg/M3. By February 1980, however, exposure to a feed mill and calender operator was reduced to 1.00 yg/M3 for NMOR, and 0.2 yg/M3 for NDMA. 

Compared to the worst case exposure from the fourth NIOSH survey, a worker in this area now would inhale approximately 6.0 yg of nitrosamines per shift, an exposure equivalent to eating a few strips of bacon and drinking a liter of beer. 

Laboratory workers handling NDMA could potentially be exposed to the nitrosamine as a result of diffusion through rubber gloves. Walker et al. (1978) showed that rubber gloves worn in research laboratories do not provide complete protection from dermal exposure to NDMA, because 11.8% of the NDMA contained in a dichloromethane solution was found to diffuse through latex surgical gloves into saline solution, over a period of 20 minutes. Dichloromethane is a common solvent for NDMA. 

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