Lab tests of 148 tins of canned tuna sold in the EU, conducted by environmental NGO Bloom, have revealed “unprecedented” levels of mercury. The French advocate alleges that international organizations and fisheries associations echo industry narratives that downplay the risks of mercury in tuna.

However, Pesca España, a Spanish association named in Bloom’s report, tells Food Ingredients First that it is “truly reassured because our statements are not based on opinion, but are based on science and rigorous scientific studies.”

Bloom reports that all the tested cans were contaminated with mercury, while 57% exceeded the strictest maximum mercury limit — 0.3 mg per kg — defined for fish in the EU.

The organization claims that a particular tin from the Petit Navire brand bought in a store in Paris, France, showed a level of 3.9 mg per kg, which it says is 13 times higher than the specified limit.

“Mercury is a powerful neurotoxin that binds to the brain and is very difficult to get rid of. Everyone knows that,” says Julie Guterman, a researcher at the NGO and the main author of the survey.

However, Pesca España says it has “never denied at any time the presence of mercury in fish.”

“We simply wanted to inform the population that it does not really pose a health risk at all. That’s because mercury possesses a strong binding affinity for selenium and acts as a magnet for selenium, which produces a non-absorbable mercury-selenium substance in the human body. As a result of this new compound, the body eliminates mercury before it is deposited in fat tissue and causes damage.”

“So, in other words, this alarmism is not real,” the association tells us.

Current mercury limits

According to the European Commission, methylmercury is the most common chemical form of mercury found in the food chain.

Fish and other seafood are the most significant contributors to inorganic mercury exposure through diet among Europeans. Fish meat is the most common exposure medium for all age groups, followed by fish products.

Mercury targets the liver, the nervous, developmental, immune and reproductive systems.

Bloom asserts that despite these concerns, European authorities set mercury limits based on contamination levels typically found in tuna instead of its health impact on adults and children. The established threshold allows 95% of them to be sold.

Bloom claims that tuna is one of the most commonly contaminated species but can contain over three times more mercury than cod, even though the risks of mercury do not differ based on the type of species.

Checks and balances

At the European level, Bloom alleges that international bodies involved in setting the standard for mercury contamination of seafood often act under the influence of “tuna giants.”