The short answer
Nitrosamines are chemicals that can form in processed foods, tobacco, and occasionally as medicine impurities. Several are probable carcinogens linked to digestive and other cancers. Diet choices, not smoking, and drug-quality controls reduce exposure.
Some nitrosamines, such as NDMA and NDEA, are classified by IARC as probably carcinogenic to humans (Group 2A).
FDA says nitrosamines are common in water and foods, including cured and grilled meats. They are also in tobacco, and some medicines have had impurities.
FDA says exposure may raise cancer risk only above acceptable levels and over long periods.
A carcinogen classification describes hazard — whether something can cause cancer — not your personal risk at a given exposure.
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The simple version
Nitrosamines are a family of chemicals. FDA says they are common in water and foods, including cured and grilled meats, dairy products and vegetables. They are also in tobacco, and some medicines have had impurities. Some are classified as probable carcinogens.
What nitrosamines are
Nitrosamines are found in water and foods, including cured and grilled meats, dairy products and vegetables (FDA). The NTP also names tobacco products as a source. Nitrosamine impurities have turned up in some medicines. FDA says recalls happen when levels pass acceptable daily limits. Recalled drugs have included certain batches of losartan, valsartan, metformin and ranitidine. Do not stop a medicine on your own. Ask your pharmacist or care team.
How people are exposed
Common ways people come into contact with them:
- Water and foods, including cured and grilled meats, dairy products and vegetables.
- Tobacco products.
- Impurities in some medicines. FDA recalls a drug when levels exceed acceptable daily limits.
The cancer connection
IARC, the World Health Organization's cancer research agency, places NDMA and NDEA in Group 2A, probably carcinogenic to humans. For NDMA this rests on inadequate human information and sufficient animal evidence. In the United States, the National Toxicology Program's Report on Carcinogens lists N-nitrosamines as reasonably anticipated to be human carcinogens.
Hazard is not the same as risk
Two ideas are easy to mix up here: hazard and risk. Calling nitrosamines a carcinogen is a claim about hazard. Hazard means they can cause cancer under some conditions. It says nothing on its own about your personal risk. FDA says exposure may raise cancer risk only above acceptable levels and over long periods. Two substances in the same group can carry very different real-world risks. The label answers whether something can cause cancer. It does not say how likely that is for you.
How to lower your exposure
- Do not use tobacco in any form.
- Ask your care team about diet. This page does not give diet targets.
- If a medicine you take is recalled, ask your pharmacist or care team what to do. Do not stop it on your own.
FDA says a person taking a drug with nitrosamines at or below acceptable daily limits for 70 years is not expected to have higher cancer risk.
If you are weighing your overall cancer risk, small steady steps add up. To see where nitrosamines sits among all the things that affect cancer risk, read our overview of cancer prevention and what raises cancer risk.
The bottom line
Some nitrosamines, such as NDMA and NDEA, are probable human carcinogens (IARC Group 2A). The most useful thing you can do is learn where exposure comes from. Then take reasonable steps to cut it, without losing sleep over a single label. Put your energy into the biggest risks you can control.
Common questions
Does nitrosamines cause cancer?
Some do, probably. IARC puts NDMA and NDEA in Group 2A, probably carcinogenic to humans, based on limited human evidence and sufficient animal evidence. The NTP lists N-nitrosamines as reasonably anticipated to be human carcinogens. Neither means proven.
How are people exposed to nitrosamines?
FDA says nitrosamines are common in water and foods, including cured and grilled meats, dairy products and vegetables. They are also found in tobacco products. Some medicines have been recalled for nitrosamine impurities.
Which cancers are linked to nitrosamines?
The sources opened for this page do not tie nitrosamines to specific cancers, so this page does not name any. Ask your care team about your own risks.
How can I reduce my exposure to nitrosamines?
Not using tobacco is the clearest step. Ask your care team about diet. If a medicine you take is recalled, ask your pharmacist or care team before stopping it.
Does a carcinogen label mean I will get cancer?
No. A classification is about hazard — whether nitrosamines can cause cancer under some conditions — not a prediction that any one exposed person will develop cancer. Your actual risk depends on the amount and length of exposure and other factors.
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Last updated: 2026-08-10Next planned review: 2028-07-05
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Cancer Explained does not originate medical claims. Every page restates guidance already published by the National Cancer Institute, the CDC, the USPSTF and the FDA, in plain language, with the source cited so you can check the original yourself. AI does the translating and organizing; automated checks test claims, citations, clarity and safety before anything publishes, and this is translation and navigation, not clinical judgment. Nothing here is personal medical advice, and no page can account for your particular situation.
Editorial status: Source checked — This page was written with AI assistance and then compared with the sources listed on it, looking for statements those sources do not back up. That check is not a sentence-by-sentence record and can miss errors. It is not a medical review, and it does not confirm the page is complete or right for your situation.
Human medical review: not completed. Pages here are not signed off by a clinician before they publish. That is not an oversight we are quietly working around: we restate published guidance and cite it, so the authority belongs to the source rather than to us, and every page names where its claims come from — you can verify us instead of trusting us. Where a volunteer clinician has reviewed a page, their name and credentials appear on it; where no name appears, no clinician has checked it. We are glad to have reviewers and are recruiting them, and we do not hold pages back waiting for one. Use this site to understand your situation and to ask better questions of the people treating you.
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