Mussels caught off California coast under quarantine due to high levels of toxins

Mussels, clams, or whole scallops caught off the coast of California should not be eaten due to the hazardous levels of a toxins that could severely sicken people, according to local and state health officials.

An annual quarantine of mussels taken by recreational shellfish harvesters went into effect Sunday due to the hazardous levels of a toxin that can cause paralytic shellfish poisoning, the Ventura County Environmental Health Division said. The quarantine applies to all species of mussels taken by the public anywhere along the California coast, but does not include commercially-harvested shellfish. 

Consumers should also not eat recreationally harvested bivalve shellfish — which includes mussels, clams, and whole scallops — after dangerous levels of domoic acid were detected in samples from the coast of Ventura County.

Paralytic shellfish poisoning can affect the central nervous system, causing tingling around the mouth and fingertips within minutes of eating tainted shellfish, and can be followed by disturbed balance, lack of muscular coordination, slurred speech, and difficulty swallowing. In a severe case, a person who has been poisoned can suffer complete muscular paralysis and death from asphyxiation. Symptoms from domoic acid poisoning can occur within a half hour of eating toxic seafood and can include vomiting, diarrhea, abdominal cramps, headache, and dizziness. In severe cases of domoic acid poisoning, a person can experience excessive bronchial secretions, difficulty breathing, confusion, disorientation, seizures, coma, and death.

Cooking does not destroy the toxins, and the quarantine will be in effect until at least Oct. 31. Health officials say mussels caught off the coast of California may be sold for bait only and must be labeled visibly as such.