This Tuesday, October 29, the NGO BLOOM, which fights against the destruction of the ocean, the climate and artisanal fishermen, unveils a shocking investigation into mercury contamination of canned tuna. Tuna is the best-selling fish in Europeas reported by communiqué of the association. But this predator, at the top of the food chain, also accumulates more heavy metals than smaller species, which increases its mercury content, underlines the World Health Organization (WHO).
Canned tuna and mercury: what to learn from the BLOOM association report?
To carry out its investigation, the NGO randomly selected 148 cans of food in five European countries, including France, and had them tested by an independent laboratory. The results showed that 100% of the boxes were contaminated with mercury. Moreover, 10% of them exceeded the authorized mercury limit for fresh tuna (1 mg/kg in Europe). “Of the 148 boxes, a box of the Petit Navire brand purchased in a Parisian Carrefour City displays a record content of 3.9 mg/kg, i.e. 13 times higher than that of species subject to the most restrictive standard of 0.3 mg/kg”indicates the press release.
Because what must be understood, underlines this report, is that the maximum levels set for the concentration of mercury in tuna and other predatory fish are three times higher than for other fish (anchovies, sardines, cod, etc.): 1mg/kg contre 0,3mg/kg. “No health reason justifies this difference: mercury is not less toxic if it is ingested via tuna, only the mercury concentration of the food matters”, BLOOM wonders.
According to BLOOM and Foodwatch, a consumer defense NGO, this standard (1mg/kg) appears abnormally high: it is not designed to protect public health but to maintain a high rate of compliance in order to facilitate the sale of tuna on the market.
“Due to the dangers posed by regular ingestion of mercury, even at low doses, all cans exceeding the standard of 0.3 mg/kg should be banned from sale. BLOOM emphasizes that current standards expose consumers to a health risk above recommended safety thresholds. The association also demands specific bans in canteens for sensitive audiences and a review of European mercury standards, for better transparency and alignment of consumption recommendations.
What are the health risks of mercury?
Mercury is a toxic metal found naturally in the soil, but its presence in the environment is mainly due to human activities, such as coal burning, industry and certain mining methods, explains the WHO. Under the action of bacteria, it transforms into methylmercury, a particularly dangerous form which accumulates in fish. The larger and higher in the food chain a fish is, the more methylmercury it contains, because it has eaten many contaminated smaller fish.
Methylmercury, classified by the International Agency for Research on Cancer (IARC) as potentially carcinogenic in 1993, accumulates in the body and causes serious health risks, particularly neuronal, cardiovascular and immune, as indicated by their classification. According to the report, the slow elimination of the body, particularly the brain, would expose regular consumers of contaminated fish to toxic and potentially carcinogenic effects in the long term. In 2016, the European Chemicals Agency (ECHA) classified methylmercury chloride as a category 2 carcinogen likely to cause cancer.
The National Health Safety Agency (ANSES) also explains that methylmercury is toxic to the human central nervous system, “particularly during in utero development and early childhood”. It could cause mild behavioral problems or developmental delays in children,”even in the absence of signs of toxicity in the mother”. The Agency therefore recommends consuming fish twice a week, varying the species and sources and limiting for pregnant womenbreastfeeding and young children fish such as tuna or pike to reduce the risks linked to methylmercury.
What alternatives to canned tuna?
If you think cooking this fish could avoid mercury contamination, think again: cooking does not eliminate mercuryspecifies the WHO on its site. In view of the various alerts concerning pollutant contamination, doctor and columnist Jimmy Mohamed recently recommended to be careful in eating fish. His advice: favor sardines, herring and mackerel as alternativesfor their similar nutritional qualities. These fish were smaller than tuna and salmon, they are less exposed to contamination by pollution. They would also have a reduced ecological impact.
Furthermore, there are other ways to benefit from the benefits found in fish, by varying your diet. Omega-3 is particularly appreciated for its beneficial effects on memory and cognitive functions. Dr Jean-Michel Lecerf, specialist in endocrinology, metabolic diseases and nutrition, highlighted during an interview for Current Woman that these fatty acids can also be found “in oil and flax seeds, avocado, hazelnuts, walnuts, chia seeds, parsley, ruffe and soy oils or watercress”.
*Following the writing of this article, Petit Navire tells us that “the consumption of Petit Navire products is perfectly safe for consumers” and that all their products are “compliant with current French and European regulations”, either with regard to tuna, a maximum mercury threshold of 1 mg/kg. The brand specifies that in this context, “we regularly carry out tests on our tuna species in our different supply areas to check the conformity of the fish we purchase and guarantee the safety of our products. These checks are carried out by or with the support of independent laboratories accredited by French and European health authorities.”
Sources :
- Mercury contamination: BLOOM reveals a public health scandal of unprecedented scale – Bloom Press release – October 29, 2024
- Mercury in tuna: the Bloom association denounces a “health scandal” and too lax regulations – Le Monde – October 29, 2024
- Mercury and health – World Health Organization – October 24, 2024
- Methylmercury: a health risk in the event of high fish consumption – ANSES – October 24, 2024
- Sardine – The WWF Fish Guide – consoguidepoisson.fr
- European Chemicals Agency ECHA CLH REPORT FOR METHYLMERCURIC CHLORIDE – March 2016
