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Mussel farms hope to harvest again soon

SHETLAND’S mussel farming industry hopes to be up and running again next month after all harvesting was stopped following an outbreak of shellfish poisoning that left around 70 people in the south east of England suffering from sickness and diarrhoea.

The algal bloom that causes diarrhetic shellfish poisoning (DSP) is a common and natural phenomenon, however shellfish growers were taken by surprise at the unprecedented speed and scale of the infestation that struck mussel farms this summer.

Environmental health inspectors said there had been a dramatic spike in DSP in Shetland around two weeks ago that allowed the contaminated mussels to slip through the rigorous monitoring regime the industry operates under.

DSP is caused by a naturally occurring phytoplankton that tends to bloom in bright sunshine and calm seas.

It has been observed spreading up the west coast of Scotland this summer, and this may be behind the Shetland outbreak.

Mussels throughout the islands’ 20 farm sites are tested every Monday and none are harvested until the test results are returned two days later.

Some farms had already stopped harvesting mussels when the contaminated batch was taken out of the sea, but when tests were carried out at the affected site the toxin was not at an unsafe level.

Shetland Islands Council environmental health manager Maggie Sandison explained: “What we have found this year is that we have more toxin than we normally do and the levels of toxin have risen more dramatically than usual.

“We will be having a full review and learning from the experience and make sure risk assessments are suitably altered to take into account the unusual circumstances we have had.”

Mussel farmers said that the DSP bloom arrived with “an incredible suddenness”.

Shetland Shellfish Growers Association chairman Kenny Pottinger said: “There have been absolutely no closures for the last two years, which has made this even more unexpected.”

He said that in the past DSP outbreaks had closed harvesting for two or three weeks, so he hoped they would be able to back in business next month.

“I think we will recover; this does not harm the mussels and the stocks will all still be there.

“I don’t think it will have a huge impact as long as it doesn’t go on for too long.”

There have to be two weeks of safe test results before harvesting is allowed to take place again.

Michael Tait, managing director of Shetland Mussels who supplied the contaminated mussels, said this was the first time this had happened in 16 years of trading and they would make sure it did not happen again.