Marrowstone Island’s rich commercial shellfish beds are clear of paralytic shellfish toxin, results from samples taken this week show.
Shellfish from beaches along Marrowstone Island, home to several shellfish companies, was found to be completely safe to eat, said Frank Cox, marine biotoxin expert with the state Department of Health on Friday.
“That area is all staying calm, so that’s good news,” said Cox, who had been concerned that commercial shellfish areas might be contaminated because of high levels of the toxin, also known as red tide, elsewhere, including at Fort Flagler State Park last week.
“But the San Juans have just gone seriously toxic” with levels of 7,000 to 8,000 milligrams of the marine toxin per sample, Cox added.
The state closes beaches to recreational shellfish harvesting when the marine toxin level reaches 80 micrograms per 100 grams of shellfish tissue.
At that level, the toxin can sickened those who eat it.
At higher levels, it can kill.
Lethal levels of from 1,000 to 2,000 or more milligrams prompted the closure of Clallam County beaches last month — a move followed first by the closure of Discovery Bay and then, last week, most other Strait of Juan de Fuca beaches in Jefferson County after a sample with 154 milligrams was found at Fort Flagler.
The levels of toxins found last week in shellfish in the San Juan Islands north across the Strait are off the chart, according to the state researcher.
“I’m shocked at how toxic the San Juans have gone,” Cox said.
A sample at Friday Harbor contained 8,283 milligrams of toxin per 100 grams of tissue. The values at two sites on Lopez Island were over 7,000 milligrams, while an Orcas Island sample contained more than 6,000 milligrams.
“I’m certain these are all-time records,” Cox said.
The highest amount found in recent tests was at March Point, south of Anacortes on Fidalgo Bay in Skagit County, where 10,932 milligrams of toxin were found in a sample, Cox said.
“I’m certain that that’s a new record,” he said.
The North Olympic Peninsula beaches on the Strait that had been closed earlier — all but those on Dungeness Bay — remain closed, Cox said.
“When you get down into Oak Bay, which is out of the Strait, beaches are still open,” he said.
Samples from the Peninsula’s ocean beaches, which are closed to harvesting for the season, also showed lethal levels of the marine toxin.
Levels of paralytic shellfish poisoning, or PSP — a toxin produced by an algae, alexandrium catenella — have been high this summer throughout the straits, researchers have said.
“PSP has been just relentless in the straits,” Cox said, “but some areas have started to show a decline.”
The bloom began in Whatcom County and the Bellingham area, stretching up to the Canadian border, he said.
At one point, the value of toxin in samples there was up to 7,000 milligrams, but last week, it had dropped to 2,000.
Even though that is still a lethal level of toxin, the drop shows that the bloom is dying back in that area.
Conditions have been right for growth of the alexandrium algae that produces the toxin.
“We had a lot of late rain that may have fertilized the water,” Cox said. High temperatures also would have fueled growth.
Choppy water discourages growth while calm seas nurture the algae.
“What’s great for water skiing is usually good for alexandrium cell growth,” Cox said.
“A lot of wave action seems to discourage growth.”
The marine toxin can cause illness or death if ingested in either cooked or uncooked shellfish.
Shellfish affected are clams, oysters, scallops and mussels.
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.
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.
Anyone experiencing these symptoms should contact a health-care provider. For extreme reactions, dial 9-1-1.
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.