Sodium nitrite in food: ingestion safety
Moderate riskIngestion of sodium nitrite-cured meat products is the primary human dietary exposure route. USDA/FDA data indicate average adult US dietary nitrite intake from cured meats is approximately 0.3–1.5 mg/day, well below the WHO Acceptable Daily Intake (ADI) of 0.06 mg/kg bw/day. However, high-frequency consumers of processed meats (bacon, hot dogs, deli meats, cured sausages) may approach or exceed the ADI. Endogenous nitrosamine formation — the critical cancer-associated step — is enhanced by: (1) concurrent consumption of protein-rich foods containing secondary amines, (2) fasting or achlorhydric conditions that raise gastric pH and promote bacterial nitrite reduction, (3) heme iron from red meat which catalyzes nitrosamine synthesis. Ascorbic acid (vitamin C) and polyphenols competitively inhibit nitrosamine formation. The 2015 IARC/WHO designation of processed meat as a Group 1 cause of colorectal cancer was partly based on the nitrite/nitrosamine mechanism, though other compounds in processed meat (PhIP, heterocyclic amines, heme iron) also contribute.
What is sodium nitrite?
Also known as: Nitrous acid, sodium salt, Nitrite, sodium, Erinitrit, Filmerine.
- IUPAC name
- sodium nitrite
- CAS number
- 7632-00-0
- Molecular formula
- NNaO2
- Molecular weight
- 68.995 g/mol
- SMILES
- N(=O)[O-].[Na+]
- PubChem CID
- 23668193
Risk for people
Moderate riskIngestion of sodium nitrite-cured meat products is the primary human dietary exposure route. USDA/FDA data indicate average adult US dietary nitrite intake from cured meats is approximately 0.3–1.5 mg/day, well below the WHO Acceptable Daily Intake (ADI) of 0.06 mg/kg bw/day. However, high-frequency consumers of processed meats (bacon, hot dogs, deli meats, cured sausages) may approach or exceed the ADI. Endogenous nitrosamine formation — the critical cancer-associated step — is enhanced by: (1) concurrent consumption of protein-rich foods containing secondary amines, (2) fasting or achlorhydric conditions that raise gastric pH and promote bacterial nitrite reduction, (3) heme iron from red meat which catalyzes nitrosamine synthesis. Ascorbic acid (vitamin C) and polyphenols competitively inhibit nitrosamine formation. The 2015 IARC/WHO designation of processed meat as a Group 1 cause of colorectal cancer was partly based on the nitrite/nitrosamine mechanism, though other compounds in processed meat (PhIP, heterocyclic amines, heme iron) also contribute.
Regulatory consensus
6 regulatory and scientific bodies have classified Sodium nitrite. The classifications differ — that's the data.
| Agency | Year | Classification | Notes |
|---|---|---|---|
| IARC | 2010 | Group 2A (probably carcinogenic to humans) | Evaluated as 'Ingested Nitrate and Nitrite, and Cyanobacterial Peptide Toxins.' IARC concluded that ingested nitrite under conditions that result in endogenous nitrosation is probably carcinogenic to humans (Group 2A), based on sufficient evidence of carcinogenicity in experimental animals and limited evidence in humans. The cancer risk is mediated through endogenous formation of N-nitroso compounds (particularly N-nitrosamines) in the stomach, particularly in the presence of secondary amines from protein-rich foods. |
| EPA CTX / Genetox | — | Genotoxicity: positive (Ames: positive, 90 positive / 11 negative reports) | |
| EPA CTX / Genetox | — | Genotoxicity: positive (Ames: positive, 90 positive / 11 negative reports) | |
| EPA CTX / Skin-Eye | — | Eye Irritation: Category 2A (score: high) | |
| EPA CTX / Skin-Eye | — | Skin Irritation: Not classified (score: low) | |
| EPA CTX / Skin-Eye | — | Eye Irritation: Category 6.4A (Category 2A) (score: high) |
Regulators apply different standards of evidence — animal-data weighting, exposure-pattern assumptions, epidemiological power thresholds — which is why two scientific bodies can review the same data and reach different conclusions. The disagreement is the data.
Where you encounter sodium nitrite
- Industrial Facilities — Manufacturing plants, Chemical storage areas, Waste treatment sites
- Occupational Environments — Factories, Warehouses, Transportation vehicles
- Food — processed food, beverages, candy, baked goods
Safer alternatives
Lower-risk approaches that achieve a similar outcome to Sodium nitrite:
-
Physical/mechanical pest control (IPM)
Trade-offs: More labor-intensive. May not be sufficient for severe infestations.Relative cost: Variable; lower long-term
Frequently asked questions
Is sodium nitrite safe for you?
Ingestion of sodium nitrite-cured meat products is the primary human dietary exposure route. USDA/FDA data indicate average adult US dietary nitrite intake from cured meats is approximately 0.3–1.5 mg/day, well below the WHO Acceptable Daily Intake (ADI) of 0.06 mg/kg bw/day. However, high-frequency consumers of processed meats (bacon, hot dogs, deli meats, cured sausages) may approach or exceed the ADI. Endogenous nitrosamine formation — the critical cancer-associated step — is enhanced by: (1) concurrent consumption of protein-rich foods containing secondary amines, (2) fasting or achlorhydric conditions that raise gastric pH and promote bacterial nitrite reduction, (3) heme iron from red meat which catalyzes nitrosamine synthesis. Ascorbic acid (vitamin C) and polyphenols competitively inhibit nitrosamine formation. The 2015 IARC/WHO designation of processed meat as a Group 1 cause of colorectal cancer was partly based on the nitrite/nitrosamine mechanism, though other compounds in processed meat (PhIP, heterocyclic amines, heme iron) also contribute.
What products contain sodium nitrite?
Sodium nitrite appears in: Manufacturing plants (Industrial facilities); Chemical storage areas (Industrial facilities); Factories (Occupational environments); Warehouses (Occupational environments); processed food (Food).
Why do regulators disagree about sodium nitrite?
Sodium nitrite has been classified by 6 agencies including IARC, EPA CTX / Genetox, EPA CTX / Genetox, EPA CTX / Skin-Eye, EPA CTX / Skin-Eye, with differing conclusions. Regulators apply different standards of evidence (animal data weighting, exposure-pattern assumptions, epidemiological power thresholds), which is why two scientific bodies can review the same data and reach different conclusions. See the regulatory consensus table on this page for the full picture.
See Sodium nitrite in the food app
Look up products containing sodium nitrite, compare to alternatives, and explore the full data record.
Open in food View raw API dataSources (3)
- IARC Monographs Volume 94: Ingested Nitrate and Nitrite, and Cyanobacterial Peptide Toxins — Group 2A Classification, Endogenous N-Nitrosation Mechanism, and Colorectal/Gastric Cancer Evidence (2010) (2010) — academic
- US FDA/USDA FSIS: Sodium Nitrite in Cured Meats — Maximum Use Levels (200 ppm), Antimicrobial Function, Methemoglobinemia Risk, and Ascorbic Acid Co-Addition Requirements (2022) (2022) — regulatory
- WHO/IARC: Processed Meat — Group 1 Carcinogen for Colorectal Cancer (2015); Sodium Nitrite and N-Nitrosamine Formation as Contributing Mechanistic Pathway; Quantitative Risk Estimate (18% per 50 g/day) (2015) — regulatory
Reference data, not professional advice. Aggregates publicly available regulatory and scientific data; not a substitute for veterinary, medical, legal, or regulatory advice. Why we built ALETHEIA →