Dutch food safety body NVWA is investigating reports that farmed Swedish salmon contaminated with high concentrations of cancer-causing dioxins has been sold in the Netherlands.

The Swedish food safety authorities have confirmed some 200 tonnes of suspect salmon has been sold to other European countries.

The EU banned the sale of salmon and herring from the Baltic Sea in 2002 because of the high levels of dioxins – between three and five times as much as is found in salmon farmed elsewhere, the BBC reported.

The fish is sold and eaten in Sweden, Finland and Latvia and the Swedish authorities say the amount of dioxin it contains is well under EU limits.

Around half the 200 tonnes was sent to France but some has also been sold in the Netherlands and Denmark, the Swedish authorities say.