Ethoxyquin dimer effects on liver and kidneys in rats
What it found
Feeding rats a breakdown product of ethoxyquin for 90 days changed liver enzyme activity and affected markers of liver and kidney function.
The study was done in animals, not people.
What they found
Animal and lab studies
Liver gene changes
In rats fed the dimer, one liver gene dropped below 3% of normal levels. Another rose to 192% of normal.
Enzyme activity shift
A gene linked to clearing chemicals rose to 144% of normal in rats. But the actual activity of that enzyme went down.
Organ health markers
Blood markers for liver and kidney function showed signs of harm in rats given 12.5 mg per kg of body weight each day.
Similar to parent compound
The dimer turned on the same enzyme systems in rats as the original ethoxyquin does.
What the authors conclude
- They found that the ethoxyquin dimer triggers the same enzyme responses in rats as the original preservative.
- Their results show the dimer can affect liver and kidney markers in animals at the tested dose.
How it was done
Ethoxyquin is added to animal feed as a preservative, and traces remain in farmed salmon fillets. In fish muscle it often turns into a paired molecule called ethoxyquin dimer, whose effects were unknown.
Male rats were fed the ethoxyquin dimer every day for 90 days. The daily dose was 12.5 mg per kg of body weight. Researchers then checked liver genes, enzyme activity, and markers of organ health.
What it can’t tell you
- We summarised it from the abstract only.
- These tests were done in rats, so they cannot show what happens in people who eat farmed salmon.
- A 90-day animal study cannot reveal long-term effects over a human lifetime.
Who paid
- Authors work at
- National Institute of Nutrition and Seafood Research, Norway
The paper
- Title
- Investigations on the metabolism and potentially adverse effects of ethoxyquin dimer, a major metabolite of the synthetic antioxidant ethoxyquin in salmon muscle
- Type
- Study
- Evidence
- Animals and lab studies
- Summarised from
- Abstract only
- Cite
- Ørnsrud R, Arukwe A, Bohne V, Pavlikova N, Lundebye AK (2011). Investigations on the metabolism and potentially adverse effects of ethoxyquin dimer, a major metabolite of the synthetic antioxidant ethoxyquin in salmon muscle. Journal of food protection. doi:10.4315/0362-028X.JFP-10-547PubMed 21902931DOI
Summary written 30 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error