(CNN)Maine's Department of Marine Resources has recalled mussels and clams harvested in the state after some tested positive for a deadly neurotoxin.
There are no reports of anyone getting sick. The department issued the recall after tests found the toxin, domoic acid, at a level that is higher than the established threshold.
The recall applies to mussels and mahogany quahogs that were harvested or wet-stored Sunday through Friday of last week in the Jonesport area of Maine, and clams that were harvested last Wednesday through Friday from Cranberry Point in Corea to Cow Point in Roque Bluffs.
Domoic acid occurs naturally in the ocean. Algae produces the chemical that can accumulate in shellfish and some fish. The toxin doesn't seem to hurt the fish, but it can hurt humans and other mammals who eat them. Freezing or cooking the fish and shellfish doesn't seem to reduce the danger.
People who get sick after eating shellfish or fish tainted with this toxin can get what's called amnesic shellfish poisoning, or ASP. ASP symptoms include abdominal cramps, diarrhea, nausea and vomiting.
will appear within 24 hours after eating the meal. If someone eats enough
of the toxin at a high enough level, it can cause neurological problems including short-term memory loss, seizures, dizziness, motor weakness, headache, seizures, cardiac arrhythmia, coma and even death.
The Maine Department of Marine Resources said the phytoplankton that creates the neurotoxin has been in the waters around the state for decades, but this is the first time shellfish in the area has tested positive for a toxin above the safety threshold.
The department told dealers to throw out the clams and mussels harvested from this period. Jeff Nichols, director of communications for the Maine Department of Marine Resources, said this is the first time Maine has issued a recall because of this toxin. It is also the first time the state has closed any part of the coast to harvesting mussels and soft-shell clams. The closure began on September 27 and expanded over the ensuing days, with closures stretching from Otter Point to the Canadian border.
"The recall, combined with the closure to harvesting, gives us every confidence that we have taken all the necessary steps to prevent impacted shellfish from making it to the public," Nichols said.
Maine is not the only state to have struggled with problems caused by domoic acid. The toxin has showed up in marine animals as far away as Alaska.
States have been testing for the chemical for years. An outbreak in Canada in the 1980s caused hundreds of people
to get sick after eating mussels with a high concentration of the chemical.
Last year, after El Niño warmed the ocean waters, creating the perfect environment for it, the West Coast saw one of the largest harmful algal blooms
in more than a decade. That meant crabbing season was closed in Washington, California
has had to cancel at least three razor clam seasons since the '90s.
People aren't the only ones who can get sick from eating the shellfish and fish. Over the years the toxinhas been blamed
for the death of whales and birds. In 1961 there was an incident in which hundreds of birds attacked people and dived through windows and crashed into trees in Capitola, California. It's believed the birds had been suffering from domoic acid poisoning. The incident was said to have inspired the Alfred Hitchcock movie "The Birds."