Recreational shellfish harvesting closures prompted by lethal levels of red tide had not moved beyond Discovery Bay in East Jefferson County, but one other East Clallam County clamming beach was closed Wednesday after unsafe levels of paralytic shellfish poisoning biotoxin were found.
Frank Cox, state Department of Health marine biotoxin coordinator, said biotoxin levels at the beach at Grays Marsh on the shores of Dungeness soared to 96 micrograms per 100 grams of shellfish tissue in water samples taken this week.
Recreational shellfish harvesting is closed when the paralytic shellfish poisoning biotoxin, or PSP, levels reach 80 micrograms per 100 grams of shellfish tissue.
That was the only significant change in red tide levels since state health and Jefferson County Public Health on Monday announced the closure of Discovery Bay to recreational shellfish harvest.
Samples from mussels taken in Discovery Bay on Monday revealed biotoxin levels at 320 micrograms per 100 grams of shellfish tissue.
“This is a serious threat,” Cox said, reaching well into lethal levels.
Tests levels of the marine toxin — which causes difficulty breathing and can be deadly — prompted the closure last week of all beaches along the Strait of Juan de Fuca from Dungeness Spit to Cape Flattery to recreational harvest — ocean beaches already being closed for the season.
“We closed the Straits for all of Clallam County, but in Sequim Bay only for butter clams,” Cox said Wednesday.
In East Jefferson County, Cox said, samples from horse clams at Cape George beach at the northeast of the mouth of Discovery Bay showed 42 micrograms.
“That’s not really significant,” he said.
Mussel samples taken at Kilisut Harbor in Mystery Bay and at Fort Flagler were less than 38 micrograms.
State health has mussel cages at Fort Flagler State Park and Mystery Bay, which are considered the “sentinel” devices in the states red tide early warning system, he said.
The cages are stocked with mussels because they tend to pick up and cleanse out toxins more quickly than other shellfish.
Butter clams hold onto toxins for the longest periods, he said, which is why beaches are often closed to harvest of that species.
Continuing closures are in effect for butter clams at the entrance to Port Ludlow and between Marrowstone and Indian islands in East Jefferson County.
Asked if there were any signs of red tide algae blooms drifting into shellfish-rich Hood Canal, Cox said, “I don’t see any evidence of that yet.”
PSP, often referred to as red tide, is caused by an algae called alexandrium cantella.
Cox said it was possible that the red tide bloom — a natural, recurring annual event cause by sunlight warming the water — may settle down soon.
To reopen beaches, he said, two samples must be taken that have readings below unsafe levels.
“To reopen, we have to look at little neck clams, butter clams and all the species like the oysters,” he said.
“We will be continuing to test daily and there will be samples coming in. Hopefully, it will be a brief bloom event.”
The highest red tide levels recorded so far on the North Olympic Peninsula this month were at Second Beach in LaPush — where the level had subsided last Friday to 2,600 micrograms from an earlier 3,600 micrograms — and Freshwater Bay near Joyce, where 3,048 micrograms were found in test samples taken June 9.
The levels were the highest seen in at least a decade, state researchers said, and tests showed it seemed to be moving east.
Those red tide levels approached the amount measured in shellfish when three Lower Elwha Klallam tribal members died after eating poisoned butter clams and mussels in 1942 — âóäthe last time any deaths from the biotoxin were recorded in the state — Cox said.
Shellfish harvesting closures include clams, oysters, mussels, scallops and other species of molluscan shellfish.
Crab meat is not known to contain the biotoxin, but the guts can contain unsafe levels. To be safe, clean crab thoroughly and discard the guts.
Marine biotoxins are not destroyed by cooking or freezing and can be life-threatening.
Symptoms of paralytic shellfish poisoning can appear within minutes or hours and usually begin with tingling lips and tongue, with the tingling moving to the hands and feet followed by difficulty breathing, and potentially death.
Any one experiencing these symptoms should contact a health-care provider. For extreme reactions call 9-1-1.
If a person consumes enough poison, muscles of the chest and abdomen become paralyzed. Death can result in as little as two hours.
In most cases the algae that contain the toxins cannot be seen, and must be detected using water sampling and laboratory testing.
Recreational shellfish harvesters should check the state health department website at www.doh.wa.gov/ehp/sf/biotoxin.htm or phone the health department’s biotoxin hot line at 800-562-5632 before harvesting shellfish anywhere in the state.
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Port Townsend-Jefferson County Editor Jeff Chew can be reached at 360-385-2335 or at jeff.chew@peninsuladailynews.com.