Nitrosamines: Carcinogenic chemical 'intruders' in occupational environments

Abstract

Nitrosamines, or more precisely N-nitrosamines, along with N-nitrosamides, belongs to N-nitroso compounds, a class of organic compounds that have a nitroso (-N=O) group attached directly to a nitrogen atom. Only a few of them occur naturally while the majority is formed by nitrosation of secondary amines in a living and working environment, food, tobacco smoke, etc. These compounds have scarce application in the industry, but they can be formed in situ, so they can be considered as chemical intruders in working environments. Considering their toxicity, especially carcinogenicity, where there is a risk of exposure to N-nitroso compounds, appropriate protection measures should be taken, including process control, work practices, protective clothing, use of respirators, legal regulations.

Use of the benchmark‐dose (BMD) approach to derive occupational exposure limits (OELs) for genotoxic carcinogens: N‐nitrosamines

“…In the leather industry, the main nitrosamines are NDMA and NMOR, while in iron and steel casting, they are NDMA and NDEA. Since the composition pattern of total nitrosamines might differ between exposure scenarios (HSE, 2010;Miltojevi c, Golubovi c, & Stojanovi c, 2021) and components (nitrosamines) may share modes of action but differ in potency, it is recommended that the limit for total nitrosamines as a mixture should be correspondingly adjusted (Equation 5). For instance, for an exposure scenario where NDMA and NMOR are in equal portions (50%/50%), an OEL for the mixture should be 0.75 μg/m 3 (Equation 5: 100/(50%/0.5 μg/m 3 ) + (50%/1 μg/m 3 ).…”