# Ozone

> Source URL: https://additivefacts.com/additives/ozone
> Markdown URL: https://additivefacts.com/additives/ozone.md

**Safety rating:** SAFE
**CAS number:** 10028-15-6
**Category:** other
**FDA GRAS:** no
**Adverse events (FDA AERS):** 0
**FDA recalls:** 0
**Last updated:** 2026-04-02

## Summary

Ozone (O₃) is a triatomic oxygen molecule used as an antimicrobial agent in food processing to reduce pathogens and extend shelf life. It is generated on-site and decomposes rapidly to oxygen, leaving no chemical residue on food products.

## Regulatory status

| Country | Status |
| --- | --- |
| United States | approved |
| European Union | not_evaluated |
| United Kingdom | approved |
| Canada | approved |
| Australia | restricted |
| Japan | not_evaluated |
| South Korea | not_evaluated |
| Brazil | restricted |
| China | not_evaluated |
| India | not_evaluated |

## Detailed analysis

## What is Ozone?

Ozone is a colorless gas composed of three oxygen atoms (O₃) that exists naturally in Earth's atmosphere. In food processing, ozone is generated on-site using electrical discharge or ultraviolet light applied to oxygen or air. Due to its unstable structure, ozone rapidly decomposes back into ordinary oxygen (O₂) within minutes to hours, depending on temperature and pH conditions. This characteristic decomposition is significant because it means no synthetic chemical residues remain on treated food.

## Common Uses

Ozone is employed in food processing primarily as an antimicrobial agent to:

- Disinfect water used in food processing and washing operations
- Treat food contact surfaces and equipment
- Reduce microbial contamination on fresh produce, grains, and other foods
- Preserve freshness by controlling mold and bacterial growth
- Sanitize storage facilities and transportation containers

Ozone treatment is particularly valued in organic and minimally-processed food production because it requires no chemical additives and leaves no toxic residues. It has been used in European water treatment and food processing for decades.

## Safety Assessment

Ozone's safety profile in food applications differs from its role as an air pollutant. When used in food processing:

**Residue concerns:** Because ozone decomposes to oxygen, no chemical residues accumulate on food products. This addresses a primary safety concern with synthetic antimicrobials.

**Worker exposure:** Occupational exposure to gaseous ozone during generation and application requires proper ventilation and monitoring, as inhaled ozone can irritate respiratory tissues. However, this is an occupational safety issue rather than a food safety concern.

**Efficacy and concentration:** Ozone's antimicrobial effectiveness depends on concentration, contact time, and environmental conditions. Treatment parameters must be carefully controlled to ensure food safety without excessive gas exposure.

**FDA data:** The FDA has recorded zero adverse events and zero recalls associated with ozone use in food processing, suggesting a strong safety record in commercial applications.

## Regulatory Status

Ozone is not listed on the FDA's Generally Recognized As Safe (GRAS) list, which may seem to suggest regulatory caution. However, this absence does not indicate disapproval. Rather, ozone operates under a different regulatory framework:

- In 2001, the FDA approved ozone as a antimicrobial agent for use in processing foods, including meat and poultry, under 21 CFR 182.2939
- The approval recognizes ozone's effectiveness and safety when used properly
- The European Food Safety Authority (EFSA) and other international bodies have similarly approved ozone for food processing applications
- Many countries permit ozone treatment of drinking water and food processing water under specific conditions

The distinction between FDA approval and GRAS status is important: GRAS status is one pathway for food additives, but direct FDA approval (as ozone has received) is equally valid.

## Key Studies

Scientific research has demonstrated ozone's effectiveness and safety:

- Studies confirm ozone's antimicrobial efficacy against bacteria (E. coli, Salmonella, Listeria) and fungi on various food products
- Research shows rapid decomposition to oxygen in food matrices, supporting the no-residue claim
- Published literature documents successful industrial applications in produce washing, grain storage, and water treatment
- Toxicological assessments have focused on gaseous ozone exposure rather than food residues, as decomposition products are non-toxic oxygen

The scientific consensus supports ozone as an effective and safe antimicrobial agent when properly applied in food processing, with its primary advantage being the absence of synthetic chemical residues.

## Sources

- FDA Substances Added to Food (CFSAN)
- OpenFDA Adverse Event Reporting System (AERS)
- OpenFDA Food Recalls
- EFSA OpenFoodTox
- EU Food Additive Portal

## Citation

Additive Facts. "Ozone — Safety, regulation, and evidence." https://additivefacts.com/additives/ozone. Accessed 2026-05-12.