Shellfish harvesting has been closed on the east shoreline of Kitsap County from Point-No-Point in Hansville to Restoration Point on Bainbridge Island, including Miller Bay and Port Madison.

Officials with the Kitsap Public Health District said recent tests of shellfish indicated high levels of marine biotoxin paralytic shellfish poison (PSP).

The harvesting ban includes all recreational shellfish harvesting for all species of clams, oysters and mussels.

Shrimp and crab were not included in the closure, but health district officials said crabs should be cleaned prior to cooking, and the “crab butter” should be discarded. Shellfish harvested commercially that are available in stores and restaurants are tested for toxins prior to distribution, and are safe to eat.

Shellfish tests were conducted on Sept. 17 by the health district, in partnership with the Washington State Department of Health and Clean Water Kitsap, and officials said results show concentrations of 172 micrograms of toxin per 100 grams of shellfish tissue.

Shellfish harvesting is closed when PSP toxin levels meet or exceed 80 micrograms per 100 grams of tissue.

Warning signs have been posted at public beaches alerting people not to collect shellfish from the closure areas.

Early symptoms of PSP include tingling of the lips and tongue, which may begin within minutes of eating toxic shellfish or may take an hour or two to develop. Symptoms may progress to tingling of fingers and toes and then loss of control of arms and legs, followed by difficulty in breathing. Some people feel nauseous or experience a sense of floating.

If a person consumes enough toxin, muscles of the chest and abdomen become paralyzed, including muscles used for breathing, and the victim can suffocate. Death from PSP has occurred in less than 30 minutes.