Shellfish poisonings prompt state warnings


June 16, 2011

 State scientists investigating a recent series of paralytic shellfish poisonings in Southeast Alaska discovered the "highest levels of toxin ever recorded," prompting the state to issue warnings for people to not eat recreationally harvested mussels, cockles, clams, oysters or scallops.

"No recreational harvest (of shellfish) is considered safe anytime of the year," said state epidemiologist Kim Porter.

The state is investigating the illnesses of more than a dozen people since May after they developed symptoms of PSP. The illnesses occurred mainly in Ketchikan and Annette Island. Shellfish is considered toxic if it contains more than 80 parts per million of the toxin. Scientists have discovered shellfish around Ketchikan with levels between 1,100 and 5,000 micrograms - and as high as 30,000 micrograms in some baby mussels. Scientists said those levels are high enough to easily cause death in people eating them.

Other scientists also have found through independent testing that local shellfish –and possibly crab - could have high levels of PSP toxin as well.

Crab and mussel samples taken from Haines in 2010 and tested recently by the Washington State Department of Health laboratory show preliminary results of high levels of toxin. Local consulting firm Chilkat Environmental and Ray RaLonde with the Marine Advisory Program at University of Alaska released the results in May after they coordinated the testing.

The crab results are considered "inconclusive" however, because the lab did not conduct confirmation testing, according to RaLonde.

Even without conclusive results, the state and RaLonde said caution should be taken with recreationally harvested crab. Crabmeat is not known to contain the PSP toxin, but the guts can. But avoiding possible illness from crab viscera is easy enough; carefully clean the crab before cooking and eating, RaLonde and the state suggest.

"Dungeness is my favorite crab," RaLonde said. "But the viscera goes down the sink."

RaLonde reiterates the same advice about shellfish the state is circulating.

"Bottom line, the PSP situation in Alaska this summer is dangerous, regardless of monitoring," he said. "Don’t eat personally harvested shellfish."


The story of the round of independent testing originates last summer.

Resident Mike Saunders died in June 2010 from suspected PSP from locally harvested crab. The state responded but officials said testing did not reveal any PSP in the samples of crab tested. Heart failure was ruled as the cause of Saunders’ death.

At the same time, the Alaska Marine Advisory Program and Chilkat Environmental coordinated a volunteer research effort, collecting a larger sample of crab and shellfish than the state took, and specifically from Jenkins Rock and Taiyasanka Harbor, the same areas from where crab was harvested for the dinner Saunders attended. The state did not have authority to do testing on those samples and so they were stored.

Several months later, the University of Alaska Southeast’s Harmful Algal Bloom Program requested and received funding from the NOAA Monitoring and Event Response for Harmful Algal Blooms program to conduct preliminary testing of the samples.

Data from the testing showed the mussels had levels of toxin well over the maximum safe level of PSP allowable for human consumption by the U.S. Food and Drug Administration. The inconclusive testing on the crab had similar results.

Chilkat Environmental and RaLonde pursued the testing because the state lacks authority to test most recreationally harvested seafood. State epidemiologists only respond to a community and conduct testing after an illness is reported. The Department of Environmental Conservation does not have beach-monitoring programs so no beaches can be certified PSP safe. Only commercially harvested shellfish and crab are routinely tested and are considered safe to eat, Porter said.

And despite some conventional thought that shellfish may be safe to eat at other times of year, the state epidemiologists do not agree.

"Although there may be seasonal variations, the state is saying that no recreational harvest is considered safe anytime of the year," Porter said.

She also said PSP, especially in small communities, tends to be under-reported. This can further limit the amount of testing the state can do to examine the PSP risks in areas. Early symptoms of PSP can include tingling lips and tongue, tingling fingers and toes and possibly loss of control of arms and legs, followed by difficulty breathing. Symptoms can appear immediately or up to two hours after poisoning. Porter said anyone with symptoms – no matter how mild – should seek medical care as soon as possible.

"Things can get very serious, very fast," Porter said.


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