"Children are the first victims": Due to its mercury content, more than ten French municipalities ban tuna from school canteens

The press release came on the first day of the school year. Eight municipalities: Bègles, Grenoble, Lille, Lyon, Montpellier, Paris, Rennes and Mouans-Sartoux announced that they were stopping offering tuna products in the canteen .

A decision taken "as a precautionary principle , to protect children's health" which is based on a study by the NGOs Bloom and Foodwatch published in October 2024 and which warned of the contamination of tuna with mercury after having 148 cans of canned tuna randomly tested by an independent laboratory.

For more than one in two cans analyzed, the mercury content exceeded the maximum limit set for other species, such as cod or anchovies, i.e. 0.3 milligrams (mg) per kilo (kg). Set at 1 mg/kg for the fresh product, the regulatory threshold for tuna, three times higher, does not take into account the concentration of mercury after processing. According to the NGO's calculations, the actual content in canned goods would thus reach approximately 2.7 mg/kg, due to the dehydration of the product. This is nine times higher than the level allowed for the majority of fish .

Mercury is classified by the World Health Organization (WHO) as one of the ten substances of greatest concern to public health .

Once ingested, "this powerful neurotoxin can lodge in the brain and have devastating effects, particularly on the neuronal development of young people (low IQ, neuromotor disorders, behavioral disorders, memory disorders, etc.)" , the press release also specifies.

"Raising awareness among families"

For the signatory cities, children are the "first victims" and " can very quickly exceed the tolerable weekly intake (TWI), that is to say the maximum quantity that can be ingested regularly over the course of a lifetime before being exposed to a health risk" .

Communities are calling on the Ministries of Health and Agriculture to ban the marketing of tuna products exceeding 0.3 mg/kg of mercury at the national level .

In recent days, the agglomeration of Mont-de-Marsan in the Landes, and closer to us, the communes of Puget-sur-Argens, but also Nice, Cagnes-sur-Mer , and Peymeinade have decided to follow the movement.

With this measure, the municipalities also want to " raise awareness among families in their personal practices " , explained Gilles Pérole, deputy delegate for Food in Mouans-Sartoux, in our columns a few days ago.

The example of Villeneuve-Loubet

Although tuna has been out of school cafeterias for a few days, precautions have been taken for several years in Villeneuve-Loubet. Marie Biamonte, a dietician at the town hall since 2020, took into account upon her arrival that " tuna is a big fish" and that it " accumulates more heavy metals than other fish ."

While continuing to follow the recommendations that advise eating fish once a week, the specialist, with the support of her municipality, preferred to offer pollock or cod for lean fish, and salmon for oily fish.

In five years, she has only very rarely offered tuna. " Since I've been in office, we've had to serve it three times in the canteen . We still did it at certain picnics once a month during the school holidays, but we were very careful about the quantity served per child."

If you want to maintain your protein and healthy fat intake, Marie suggests a menu with a starter of sardine or herring rillettes, followed by a lentil curry with coconut milk and rice or vegetable lasagna with green salad. "For dressing the green salad, you can use olive oil, but also walnut or sesame oil." And finish with yogurt.

" Collective catering is a powerful lever ; its weight in the food industry gives it a strong impact. It's excellent that other communities are taking this path. But let's not forget that change also starts at home."