A French food safety agency has warned of a possible health risk due to consumption of pinnatoxin-contaminated shellfish.

The French Agency for Food, Environmental and Occupational Health and Safety (ANSES) looked at pinnatoxins (PnTXs), a family of marine biotoxins detected in mussels from Mediterranean lagoons.

The agency recommended the emerging biotoxins are included in monitoring of shellfish production areas and research is done to accurately estimate the exposure of shellfish consumers.

Experimental studies in mice have shown acute toxic effects that can be fatal if high doses are ingested. No cases of pinnatoxin poisoning in humans have been reported so far in France or worldwide.

ANSES identified a provisional acute benchmark value for pinnatoxin G, one of the eight toxins in the family, and the one most commonly detected in shellfish in France.

This value of 0.13 µg PnTX G per kilogram of body weight means with a default serving size of 400 gram of shellfish and a body weight of 70 kilogram, the concentration not to be exceeded in shellfish would be 23 µg PnTX G per kilogram of total meat. In cases of high consumption and/or high contamination the benchmark value could be exceeded.

Pinnatoxin concentrations detected
Pinnatoxins are produced by marine microalgae called Vulcanodinium rugosum that can accumulate in shellfish. These marine biotoxins were identified in France in 2011 in mussels from the Ingril lagoon in the Hérault region by the French Research Institute for Exploitation of the Sea (Ifremer). Since then, analyses have shown high concentrations of them for several months each year.

Concentrations varied greatly depending on the year, there was a maximum of 1,244 μg of PnTX G per kilogram of shellfish (wet weight) in 2010. In July 2015, a concentration of 1,143 μg of PnTX G per kilogram of shellfish was reported. Concentrations of PnTX G measured in mussels from Ingril are the highest reported in the world to date. Levels of up to 95 µg per kilogram of total meat have been reported in clams.

Pinnatoxins have also been detected in other regions of France and in mussels from other Mediterranean lagoons (Vic, le Prévost, Thau, Leucate) and on the Atlantic and Corsican coasts. Data on shellfish contamination has also been reported in Canada, Australia, New Zealand, and in Northern and Southern Europe.

PnTXs have a rapid mode of action, with death in mice occurring within 30 minutes of administration. Symptoms observed are neurotoxic such as paralysis and respiratory distress.

ANSES concluded there is a possible health risk associated with consumption of pinnatoxin-contaminated shellfish from Mediterranean lagoons, particularly the Ingril area. There is currently no shellfish production intended for sale from the area but the agency alerted public authorities about the need to avoid all consumption of shellfish from this area.