The State Department of Health and Social Services is warning residents to exercise caution when collecting shellfish in Homer harbor.
Recent tests have shown elevated saxitoxin levels in blue mussels.
Catherine Bursch, the harmful species program coordinator at Kachemak Bay Research Reserve, samples blue mussels every two weeks in Homer harbor to monitor for toxins.
“We did pick up over the regulatory limit of toxins in the shellfish that we sample regularly from the Homer harbor,” said Bursch.
These naturally occurring toxins are produced by microscopic one-celled creatures called phytoplankton.
Phytoplankton are eaten by larger species of plankton, which are prey for filter-feeding animals, including clams and mussels.
The toxins become more and more concentrated as they move up the food chain.
When humans eat contaminated shellfish, it can cause an illness called paralytic shellfish poisoning.
The symptoms include tingling lips and mouth, nausea and difficulty breathing.
The toxins can cause paralysis and death when consumed in large enough quantities.
Although these toxin-producing plankton are almost always present in the water, at certain times of year, their populations increase. That’s when the risk of paralytic shellfish poisoning is highest.
While commercially produced shellfish are tested regularly, recreational shellfishing areas may not be, Bursch said.
“If you dig shellfish recreationally, you have to understand that no one is testing the beach,” Bursch said. “The state does not have a program that tests random beaches for the recreational harvesters.”
According to Alaska state policy, recreational shellfish harvesters dig at their own risk.
