Nurseries ban tinned tuna over mercury level worry

Kids chop vegetables at a table in a nursery
Acorns Nurseries has replaced tuna with pilchards on its menu [Acorns Nurseries]

A nurseries director has said it was an "easy decision" to ban tinned tuna and replace it with pilchards and mackerel after new research revealed it can contain toxic levels of mercury.

Cherie Wilson, who manages 11 Acorns Nurseries across south Wales and south west England, said the decision was made after conversations with parents and the chefs.

The study by campaign groups Bloom and Foodwatch sampled 148 cans of tuna from five European countries which all tested positive for mercury contamination.

But Europêche, which represents fishing fleets in the EU, said it "strongly refutes" the claims, and the amounts required to pose a health risk were "significantly higher" than what is typically consumed.

The tuna canning process means that mercury concentration is doubled or tripled, according to Bloom.

"We heard that tuna may pose a risk over time, especially with young children," said Ms Wilson.

She said it was a surprise to hear about the findings, as tuna has "always been an option" on their menu.

Alternatives have since been introduced at Acorns Nurseries, whose sites include Bristol, Cardiff and Newport.

"We are offering other oily fish such as pilchards and mackerel, which supports the growth and development in children," she said.

Cherie Wilson, Acorns Nurseries Director, smiling looking at the camera. She is seated at a table
Cherie Wilson says it is a surprise there is not more awareness about mercury contamination [Acorns Nurseries]

Tests carried out showed all 148 cans of tuna tested positive for mercury contamination.

The samples were bought in France, Germany, England, Spain and Italy.

Currently, EU and UK regulations set the mercury limit in tuna at 1 mg/kg. The mercury threshold is three times higher for tuna than for other fish species.

Tinned tuna sits on a shop shelf as a customer looks at it
Bloom and Foodwatch have launched a petition targeting European retailers [EPA]

Aisling Pigott-Jones, a member of the British Dietetic Association who works in Wales, thinks the campaigners have a point.

She said tinned tuna consumption should be "limited for children", but disagrees that it should be banned in schools.

"Eating tuna too regularly can mean higher than recommended mercury intake," she said.

"About twice a week is recommended as safe for children."

She highlighted the benefits of eating the saltwater fish, including its relatively low price.

“Tinned tuna is a good source of protein for young people, especially in the cost of living crisis”.

She said other options were available such as tinned salmon, sardines and mackerel.

Where does the mercury come from?

The poisonous element is released by mining and burning coal and ends up in the ocean.

It builds up in tuna when they consume contaminated prey.

People are then exposed to the element when they eat the fish, one of the most widely consumed around the world.

A school of  fish swim through the ocean. Several tuna are seen along with a species of shark.
Mercury levels have fallen dramatically in the atmosphere - but remained stable in tuna since 1971 [Getty Images]

The UK's biggest tinned tuna brand, John West, which is owned by the Thai Union Group, said: “The tuna products we supply to UK and European retailers are safe for consumers".

"In the past three years, we have carried out hundreds of checks. The results have never revealed mercury levels higher than the British and European standards in place".

Mark Willis, of the Food Standards Agency, said those who are pregnant should have no more than four cans of tuna a week.

But he added that mercury was found in all fish, so it "cannot be eliminated entirely".

The Food Standards Agency said it kept contaminants such as mercury in food under review.

Primary school children get free school meals across Wales as part of the Welsh government’s commitment to tackle child poverty.

The Welsh government said: "All local authorities and governing bodies of maintained schools must comply with the Healthy Eating in Schools Regulations 2013."

"The Food Standards Agency in Wales has government responsibility for food safety and any change to what can be provided in school meals on a food safety basis would be based on their advice."