What is Ethylene Oxide?
Ethylene oxide (EtO) is a flammable, colorless gas primarily used in industrial settings to manufacture other chemicals like antifreeze. It is also widely used for sterilizing medical devices and, historically, as a pesticide for food commodities. When used in food production, particularly during the fumigation of dry goods to prevent microbial growth, residues of EtO can be left behind if not properly aerated. In food products, EtO can also form toxic byproducts, most notably 2-chloroethanol (2-CE).
Common Food Products Affected
While ethylene oxide is not intentionally added to food in many regions, residues from its use as a fumigant in other countries can contaminate imports. The following product categories have been subject to recalls or are known to have had detectable levels of ethylene oxide and its metabolites:
- Sesame Seeds: The widespread EU recalls in 2020 began with contaminated sesame seeds imported from India, a major incident that expanded scrutiny across the food industry.
- Spices and Herbs: Various dried spices and herbs, including turmeric, ginger, black pepper, and cinnamon, have been found to contain residues. In the past, the US EPA set specific tolerances for EtO in spices.
- Food Additives: Thickening agents derived from certain seeds are a significant source of contamination. These include:
- Locust Bean Gum (E410): Often used in ice cream, spreads, and baked goods.
- Guar Gum (E412): Used in a wide range of products including ice cream, sauces, and soups.
- Nuts: Walnuts have been mentioned historically in relation to ethylene oxide treatment.
- Processed Foods: Contamination can spread to processed and composite products that use contaminated ingredients. This includes items like ice cream, cookies, bread, certain cereals, and instant noodles.
- Dried Fruit and Vegetables: Raisins and certain dried vegetables have been listed among the commodities where EtO residues have been detected.
A Global Regulatory Split
The global approach to regulating ethylene oxide in food differs significantly, which complicates international trade and consumer safety. For consumers, this can mean that a product legally sold in one country might be subject to recall in another.
Comparison Table: Ethylene Oxide Regulations
| Feature | European Union (EU) | United States (US) |
|---|---|---|
| Regulatory Status | Use of EtO on food and feed is banned. | Use is permitted for specific food commodities as a fumigant. |
| Tolerance/MRL | Maximum residue level (MRL) is set at the limit of quantification (LOQ), effectively meaning zero tolerance. | Tolerances are set for residues on certain commodities, e.g., 7 ppm on sesame seeds and spices, and 50 ppm on walnuts. |
| Recent Incidents | Initiated mass recalls and heightened import controls after discovering contamination in sesame seeds and other products starting in 2020. | Draft risk assessments and ongoing registration reviews, with discussions to potentially remove tolerances. |
Health Risks of Ethylene Oxide Ingestion
Ethylene oxide is a genotoxic carcinogen, meaning it has the potential to damage genetic material (DNA) and cause cancer. Regulatory bodies like the EU take a precautionary approach, asserting that no safe level of exposure can be established for consumers. Long-term exposure has been linked to an increased risk of specific cancers, such as leukemia and breast cancer, though exposure via food is typically lower than in occupational settings. The breakdown product, 2-chloroethanol, is also toxicologically evaluated as being similar to ethylene oxide due to data gaps and suspected mutagenic effects.
What Consumers Can Do
For consumers, especially in regions with strict regulations, contamination often stems from imported ingredients. Here are some steps you can take:
- Monitor Food Recalls: Stay informed about alerts from food safety authorities, such as the EU's Rapid Alert System for Food and Feed (RASFF), which are often reported by national agencies.
- Vet Your Brands: Be aware of products and brands affected by previous recalls, and consider sources that provide robust testing documentation for their ingredients, particularly if they are imported.
- Understand Sourcing: When purchasing products known to be affected, such as sesame seeds or spices, investigate their country of origin and the importer's quality control standards. Contamination often occurs in countries where EtO is still used as a fumigant.
- Buy Certified Products: Look for organic or other certifications from reputable organizations, as these often have more stringent requirements concerning pesticide and fumigant use. However, even organic products have been subject to recalls, demonstrating the complexity of global supply chains.
Conclusion
While ethylene oxide is not a food ingredient, its use as a fumigant and sterilant in some regions has led to concerning residues in a variety of food products worldwide. The 2020 European food safety incident exposed systemic vulnerabilities in global food supply chains, prompting tighter regulations and more rigorous testing. For consumers, the key lies in staying informed, understanding the origin of their food, and relying on reputable suppliers to minimize potential exposure to this carcinogenic substance. Continued vigilance from both consumers and regulatory bodies is essential to ensuring food safety standards are met globally. More information on recalls related to this issue can be found through independent watchdogs like Foodwatch EN.
