Quartermaster Harbor on Vashon-Maury Island in Puget Sound is closed to recreational shellfish harvesting until further notice because of unsafe levels of paralytic shellfish poison (PSP). The Washington Department of Health posted the closure today for recreational harvesting, noting that the harbor remains open to commercial harvest.

The closure includes all species of shellfish including clams, geoduck, scallops, mussels, oysters, snails and other invertebrates. Crab and shrimp are not included in the closure. “Crabmeat is not known to contain the PSP toxin, but the guts can contain unsafe levels. To be safe, clean crab thoroughly and discard the guts,” health officials said in the warning. “Commercial beaches are sampled separately and commercial products should be safe to eat.” PSP toxin is produced by a naturally occurring marine organism, according to the health department. The toxin is not destroyed by cooking or freezing. It is not detectable by visual inspection of the water or shellfish. “The term ‘red tide’ is misleading and inaccurate. PSP can only be detected by laboratory testing,” the health department warns. Symptoms of PSP usually begin 30-60 minutes after eating contaminated shellfish, but sometimes it may take several hours for symptoms to develop. Generally, symptoms are mild, beginning with numbness or tingling of the face, arms and legs. This is followed by headache, dizziness, nausea and loss of muscle coordination. Sometimes a floating sensation occurs. In cases of severe poisoning, muscle paralysis and respiratory failure occur, and in these cases death may occur in two to 25 hours. If symptoms are mild, call your health care provider or Washington Poison Center (800-222-1222), and Public Health (206-296-4774). If symptoms are severe, call 911 or have someone take you to the emergency room immediately. Recreational shellfish harvesters are urged to call the health department’s Biotoxin Hotline at 800-562-5632 or visit the shellfish safety website before harvesting shellfish anywhere in Puget Sound. (To sign up for a free subscription to Food Safety News, click here.)