EFSA FEEDAP — ethoxyquin (EQ) feed-additive safety
Source: EFSA FEEDAP scientific opinion, EFSA Journal 2022;20(3):7166 (DOI 10.2903/j.efsa.2022.7166), retrieved 2026-08-06 via Europe PMC OA full-text XML. Paraphrase of an EFSA opinion that the source XML tags CC-BY-ND; per project COPYRIGHT_POLICY only facts/numbers/proper-nouns are quoted verbatim, sentences rewritten.
Editorial context (read this before using the data point)
This is the EFSA FEEDAP jurisdiction on the controversial pet-food preservative ethoxyquin (EQ). It is highly pet-relevant because the Panel explicitly excludes cats from the safe level and flags a mutagen-impurity caveat. Read with the efsa contaminant/antioxidant endpoints and the existing EFSA_FEEDAP_pet_food_additives_dossiers topic.
Key findings (paraphrase; numbers and proper nouns verbatim from source)
- EQ is synthesised from p-phenetidine, a recognised possible mutagen that remains in the additive as an impurity. The applicant proposed a revised specification of p-phenetidine < 2.5 mg/kg additive, shown to be met in pilot batches.
- From tolerance studies, 50 mg EQ/kg complete feed was considered safe for chickens for fattening, laying hens, piglets, cattle for fattening and salmon; this was extrapolated to all animal species and categories except cats, for which the Panel could not conclude a safe level.
- Because the additive contains p-phenetidine (possible mutagen), the Panel could not conclude on EQ safety at any level for long-lived and reproductive animals.
- A maximum total concentration of 50 mg EQ/kg complete feed for all species except dairy animals would not leave residues posing a consumer risk (assumption: 50 mg expressed as the sum of EQ, EQDM, EQI and DHEQ). No conclusion on consumer safety for milk-producing animals (no residue data in milk) or on p-phenetidine residues.
- User/environment: inhalation exposure of unprotected users to p-phenetidine cannot be excluded; an aquatic-compartment risk cannot be excluded when the additive is used in terrestrial animals.
Pet-food relevance
Ethoxyquin is a common pet-food preservative. The cat exclusion and the p-phenetidine (possible mutagen) impurity caveat are the most decision-relevant points for cat-food formulators.
Scope note / honest gap
Paraphrase of an EFSA opinion; full quantitative risk detail (MRL tables, study statistics) is not reproduced. Source XML licence tag was CC-BY-ND, so this topic quotes only data points verbatim and rewrites prose.