N-Nitrosodimethylamine (NDMA) is primarily known as a hazardous byproduct rather than a deliberately used chemical. It commonly forms during industrial processes, especially in the production of rubber, pesticides, and dyes, where dimethylamine and nitrosating agents are present. It can also be generated during water disinfection when chlorine-based disinfectants react with organic amines in source water. NDMA has been detected in certain pharmaceuticals, particularly in some angiotensin II receptor blockers (ARBs) and ranitidine, leading to product recalls due to its potent carcinogenicity.

Due to its high toxicity and classification as a probable human carcinogen, NDMA has no safe level for human exposure. Its presence is strictly regulated in drinking water, food, and drug products. Monitoring and controlling NDMA formation is critical in environmental chemistry, pharmaceutical manufacturing, and public health safety protocols. Analytical methods are routinely employed to detect trace levels in water and consumer products to minimize exposure risk.