Fishmeal is used as an ingredient in fish feed, and feeding trials with fish have shown that ethoxyquin is transferred to a certain extent from the feed to the muscle tissue. Ethoxyquin is not authorised as a food additive in the EU.
Ethoxyquin is not found in wild fish, but may be present at low levels in farmed fish.
Ethoxyquin exposure has not been found to have any effect on humans, but liver and kidney damage has been seen in rats following exposure to high doses of ethoxyquin. However, knowledge on the toxicity of ethoxyquin’s main metabolites is limited.
There is no maximum level for ethoxyquin in fish. The acceptable daily intake of ethoxyquin derived by the JMPR is 0.005 mg per kg body weight per day. A large portion (300 grams) of farmed salmon would contribute less than 15 per cent of the acceptable daily intake of ethoxyquin.
In salmon, ethoxyquin is largely converted into ethoxyquin dimer (EQDM). Trials on rats have shown that they tolerate large doses of EQDM.
Threshold value in feed
In fish feed, the maximum level for the sum of synthetic antioxidants (EQ, BHA, BHT, PG and OG) is 150 milligrams per kilograms of feed. The levels of ethoxyquin in fish feed is monitored by the Norwegian Food Safety Authority in a feed monitoring programme, no feeds analysed to date have contained ethoxyquin levels which exceed the maximum level and the levels in feed have decreased during the last decade.