Ethylene oxide: cause for concern in the food supply chain?

Ethylene oxide is a chronic, rather than acute, food safety hazard. The 2-chloroethanol by-product of ethylene oxide is a suspected mutagen and carcinogen [3, 4]. The use of ethylene oxide, and 2-chlorethanol, is banned in the European Union (EU) and a maximum residual limit (MRL) is set e.g. for sesame seeds at 0.05 mg/kg (ppm) [5]; see Commission Regulation (EU) 2015/868. However, globally ethylene oxide is approved for use as an antimicrobial product and Codex has set no MRLs for ethylene oxide [2, 6]. The United States (US) has set an MRL of 7 mg/kg (ppm) for certain foods (spices, dried herbs, sesame seeds), but this rises to 50 mg/kg (ppm) for walnuts [7].  Canada has been consulting on the MRL for ethylene oxide, but currently has the same MRLs as the US for ethylene oxide and 2-chloroethanol, across a range of food products [8]. Ethylene oxide is currently undergoing a registration review in the US, and the draft risk assessment contains a recommendation to remove the MRL for ethylene oxide [2, 9].

The German Federal Institute for Risk Assessment (BfR), in their health risk assessment issued on 1 September 2021, stated: ‘ … ethylene oxide is mutagenic and carcinogenic … the intake of low concern [is] as low as 0.037 micrograms per kilogram of body weight per day [12]’. The sampling rate for sesame seeds was set at 50% for pesticide residues. This regulation came into force on 25 October 2020. Various technical meetings took place to discuss the issue at EU Member State level, and as a result the Commission Implementing Regulation (EU) 2020/1540 was issued. Commission Implementing Regulation (EU) 2021/2246 of 15 December 2021 amending Commission Implementing Regulation (EU) 2019/1793 imposed special conditions regarding the import of certain goods arriving into the EU, including xanthan gum from China, locust beans (including mucilages and thickeners derived from locust beans), guar gum, several spices, calcium carbonate and food supplements containing botanicals from India, food supplements containing botanicals and instant noodles from South Korea, locust beans (including mucilages and thickeners derived from locust beans) from Malaysia and Turkey, as well as instant noodles from Vietnam. These goods were included in Annex II to Implementing Regulation (EU) 2019/1793 and a sampling frequency of identity and physical checks by officials, was set at 20%. Consignments are required to be accompanied by the following documents:

1. a laboratory analysis report from testing carried out by a competent authority in the originating country, performed by laboratories accredited in accordance with the standard ISO/IEC 17025 on ‘General requirements for the competence of testing and calibration laboratories’
2. an official certificate issued by a competent authority.

Commission Implementing Regulation (EU) 2020/1540 of 22 October 2020 amending Commission Implementing Regulation (EU) 2019/1793 highlighted concerns with sesame seeds originating in India and the presence of ethylene oxide contamination [15]. The 5th revision of Regulation (EU) 1793/2019 included, in its Annex II, newly listed crop/countries combinations due to the risk of ethylene oxide contamination and it was adopted (15 December 2021), published (17 December 2021), and entered into force on 6 January 2022. [13,14]. It does not apply directly to Great Britain (GB), but inspectors at GB ports use this legislation to inform their risk-based frequencies of sampling. The European Commission amended food additive requirements, setting a maximum ethylene oxide level of 0.1 mg/kg. Commission Regulation (EU)2022/1396 amends Commission Regulation (EU) No. 231/2012. The new requirement is applicable to all products that have or contain an E number. 
 
In GB, the Food Standards Agency (FSA) initially launched a consultation to update Retained Regulation 2019/1793.  This proposal did not specifically include the list of goods added to the EU Regulation however, the GB is considering food safety and public health risks in ‘High Risk Food and Feed Not of Animal Origin’ (HRFNAO). In GB, there are no additional requirements for documentation for the import of these goods as they are not in the scope of the current retained Regulation. For any products that have been listed as HRFNAO, an official certificate and laboratory analysis report are required for export into the EU.

Food traded in Northern Ireland (NI) has to comply with EU MRLs. For food traded in GB, MRLs are listed on the Statutory Register, but for ethylene oxide these mirror EU MRLs.  For additives, FSA enforcement policy applies the EU limit of 0.1 mg/kg for ethylene oxide in business-to-business (B2B) food additives. However for final product, where ethylene oxide is present as a result of a food additive raw materials where the level was over 0.1 mg/kg, a recall is not necessarily required (unlike EU). Decisions are made on a case by case risk assessment. For more details on GB MRLs, see the online Statutory Register https://secure.pesticides.gov.uk/MRLs/Main  

Government risk communication activities need to warn of the cumulative effect of eating a diet that contains ethylene oxide. Businesses need to have agile risk management strategies in place. The incident shows the strength of collaborative food safety governance, between public and private organisations, where data from public and private surveillance can be used to determine the breadth and depth of an incident [2].