Food & Drink / Compounds / Boric acid

Boric acid in food: ingestion safety

Moderate risk

Ingestion is the primary relevant exposure route for boric acid toxicity in humans and animals. Boric acid is water-soluble and readily absorbed from the GI tract. The oral LD50 in humans is estimated at approximately 640 mg/kg for adults — considerably higher than for many acutely toxic household chemicals. Ingestion of commercial ant and roach bait products (0.5–10% boric acid) by adults causes primarily GI irritation (nausea, vomiting). Substantial ingestion of boric acid powder (grams rather than milligrams) produces a characteristic blue-green emesis due to boron's color, followed by progressive nausea, vomiting, diarrhea, and in severe cases CNS signs and renal toxicity. The primary risk from ingestion is cumulative over time rather than from a single large exposure in the context of typical consumer product use. The major population-level concern is children who repeatedly access ant bait stations and pets (especially cats) who groom after contact with borate carpet treatments.

What is boric acid?

Also known as: Orthoboric acid, Boracic acid, Borofax, Boron hydroxide.

IUPAC name
boric acid
CAS number
10043-35-3
Molecular formula
BH3O3
Molecular weight
61.84 g/mol
SMILES
B(O)(O)O
PubChem CID
7628

Risk for people

Moderate risk

Ingestion is the primary relevant exposure route for boric acid toxicity in humans and animals. Boric acid is water-soluble and readily absorbed from the GI tract. The oral LD50 in humans is estimated at approximately 640 mg/kg for adults — considerably higher than for many acutely toxic household chemicals. Ingestion of commercial ant and roach bait products (0.5–10% boric acid) by adults causes primarily GI irritation (nausea, vomiting). Substantial ingestion of boric acid powder (grams rather than milligrams) produces a characteristic blue-green emesis due to boron's color, followed by progressive nausea, vomiting, diarrhea, and in severe cases CNS signs and renal toxicity. The primary risk from ingestion is cumulative over time rather than from a single large exposure in the context of typical consumer product use. The major population-level concern is children who repeatedly access ant bait stations and pets (especially cats) who groom after contact with borate carpet treatments.

Regulatory consensus

12 regulatory and scientific bodies have classified Boric acid. The classifications differ — that's the data.

AgencyYearClassificationNotes
EPA CTX / EPA OPP—Group E Evidence of Non-carcinogenicity for Humans
EPA CTX / Genetox—Genotoxicity: negative (Ames: negative, 1 positive / 19 negative reports)
EPA CTX / Genetox—Genotoxicity: negative (Ames: negative, 1 positive / 19 negative reports)
EPA CTX / Skin-Eye—Eye Irritation: Category 2 (score: high)
EPA CTX / Skin-Eye—Skin Irritation: Category 2 (score: high)
EPA CTX / Skin-Eye—Eye Irritation: Category 6.4A (Category 2A) (score: high)
EPA CTX / Skin-Eye—Skin Irritation: Category 6.3B (Category 3) (score: moderate)
EPA CTX / Skin-Eye—skin irritation: in vivo: Studies Indicate No Significant Irritation (score: low)
EPA CTX / Skin-Eye—eye irritation: in vivo: Studies Indicate No Significant Irritation (score: low)
EPA CTX / Skin-Eye—skin irritation: in vivo: Ambiguous (score: not classifiable)
EPA CTX / Skin-Eye—eye irritation: in vivo: Moderate or Mild Irritation (score: moderate)
EPA CTX / Skin-Eye—skin sensitisation: in vivo (non-LLNA): Not likely to be sensitizing (score: low)

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 boric acid

  • 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 Boric acid:

  • Physical/mechanical pest control (IPM)
    Trade-offs: More labor-intensive. May not be sufficient for severe infestations.
    Relative cost: 1.2-2×
  • Vitamin E (tocopherols)
    Relative cost: 1.2-2×
  • Rosemary extract
    Relative cost: 1.2-2×
  • Ascorbyl palmitate
    Relative cost: 1.2-2×

Frequently asked questions

Is boric acid safe for you?

Ingestion is the primary relevant exposure route for boric acid toxicity in humans and animals. Boric acid is water-soluble and readily absorbed from the GI tract. The oral LD50 in humans is estimated at approximately 640 mg/kg for adults — considerably higher than for many acutely toxic household chemicals. Ingestion of commercial ant and roach bait products (0.5–10% boric acid) by adults causes primarily GI irritation (nausea, vomiting). Substantial ingestion of boric acid powder (grams rather than milligrams) produces a characteristic blue-green emesis due to boron's color, followed by progressive nausea, vomiting, diarrhea, and in severe cases CNS signs and renal toxicity. The primary risk from ingestion is cumulative over time rather than from a single large exposure in the context of typical consumer product use. The major population-level concern is children who repeatedly access ant bait stations and pets (especially cats) who groom after contact with borate carpet treatments.

What products contain boric acid?

Boric acid 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 boric acid?

Boric acid has been classified by 12 agencies including EPA CTX / EPA OPP, 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 Boric acid in the food app

Look up products containing boric acid, compare to alternatives, and explore the full data record.

Open in food View raw API data

Sources (3)
  1. US EPA: Boric Acid and Sodium Tetraborate — Reregistration Eligibility Decision (RED) and Human Health Risk Assessment (2006) — regulatory
  2. EFSA: Re-evaluation of Boric Acid (E 284) and Sodium Tetraborate (Borax, E 285) as Food Additives — ADI and Reproductive Toxicity Assessment (2013) — regulatory
  3. ASPCA Animal Poison Control Center: Boric Acid and Borate Insecticide Toxicosis in Dogs and Cats (2022) — veterinary

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 →