Diarrhetic Shellfish Poison (DSP) has been detected at unsafe levels in Quartermaster Harbor shellfish on Vashon-Maury Island. As a result, the Washington State Department of Health (DOH) has closed Quartermaster Harbor beaches to recreational shellfish harvest.
The closure includes clams, oysters, mussels, oysters, geoduck and scallops. Working with partners, Public Health – Seattle & King County is posting advisory signs at beaches warning people to not collect shellfish.
Commercial beaches are sampled separately and commercial products should be safe to eat.
Although DSP has been a problem in European countries for some time, this is an emerging health threat for Washington. Anyone who eats DSP contaminated shellfish is at risk for illness.
What are the symptoms of Diarrhetic Shellfish Poisoning (DSP)?
DSP poisoning symptoms include nausea, vomiting, abdominal pain and diarrhea with diarrhea being the most commonly reported symptom. Symptoms may appear within minutes of eating contaminated shellfish or may take several hours.
Naturally occurring algae produces the toxin. The toxin is not destroyed by cooking or freezing. A person cannot determine if DSP toxin is present by visual inspection of the water or shellfish. DSP can only be detected by laboratory testing.
Recreational shellfish harvesting can be closed due to rising levels of DSP at any time. Therefore, harvesters are advised to call the DOH Biotoxin Hotline at 1-800-562-5632 or visit the Biotoxin Website before harvesting shellfish anywhere in Puget Sound.