I still remember a typical morning in the Indian household of the 1990s, when I was a child: The day would begin with a freshly prepared breakfast, seasonal vegetables, and zero to limited processed food. Fast forward to today: packaged foods, pharmaceuticals, industrial products and global supply chains are integral to not just every meal but to everyday life. Hidden within this transformation is a group of chemicals known as nitrosamines.
Nitrosamines are a class of compounds that have been linked to potential health risks, including cancer, even at very low concentrations over long-term exposure. Formally named N-nitrosamines, these compounds get formed when amines (organic compounds, such as amino acids or proteins) react with nitrites or nitrates (often found in preservatives, food additives or environmental sources) under specific conditions, such as acidic environment, heat and presence of oxidising agents.
Human exposure to nitrosamines can be through ingestion, inhalation and dermal contact. Formation of nitrosamine in foods occurs either during preparation or storage, or in the stomach. Fried, grilled or cured meats are the most common dietary sources. Nitrosamines formation can also happen during curing, fermentation and storage of foods.
The other major sources of nitrosamines are contaminated water, pharmaceuticals and tobacco products. In water, these get formed during disinfection, especially when chloramine or chlorine reacts with nitrogen compounds. “During wastewater treatment, nitrosating agents react with organic compounds and this leads to nitrosamine synthesis. If this water is discharged or flows into a waterbody, it can transfer and lead to bioaccumulation in aquatic organisms, posing risks to fish and other lifeforms,” Divya Upadhyay, an aquatic toxicologist and nitrosamine expert, tells Down To Earth (DTE).
Even treated drinking water may contain nitrosamines. One of the most concerning nitrosamines in water is NDMA (N nitrosodimethylamine), a potent carcinogen found in drinking water sources globally, including India. Several nitrosamines…
This article was originally published in the August 1-15, 2026 print edition of Down To Earth