Local shellfish harvesting closed due to high biotoxin levels. Here are the areas to avoid

The shellfish harvest biotoxin closure has expanded to Henderson Inlet, Thurston County Public Health and Social Services announced Friday morning.

People are advised to avoid recreational shellfish harvesting in Eld Inlet due to high levels of a dangerous biotoxin, according to Thurston County.

The county declared the closure of recreational shellfish harvesting for all species in Eld Inlet on Tuesday after announcing similar closures in several nearby areas.

So far, Budd Inlet, Dana Pass, Pickering Passage and Peale Passage have been closed as well, according to the county’s Public Health and Social Services Department. The affected areas include Burfoot Park, the Boston Harbor area, Hope Island and much of Harstine Island.

The biotoxin that’s causing the closures produces diarrhetic shellfish poisoning (DSP). This can cause nausea, vomiting, abdominal pain and diarrhea if people eat affected shellfish. DSP is non-lethal to humans, according to the Washington State Department of Health.

Naturally occurring plankton produce biotoxins, per the county. While the biotoxins do not harm shellfish, the county says they can cause illness or death in humans and other mammals that consume them.

Harvesters stay to date about closures by visiting an online shellfish safety map by the or calling 1-800-562-5632. Additional information can be found on the Washington State DOH website.