SACRAMENTO – The California Department of Public Health (CDPH) is advising consumers not to eat recreationally harvested mussels, clams or whole scallops from Humboldt County. Dangerous levels of domoic acid have been detected in mussels from this region. This naturally occurring toxin is also referred to as Amnesic Shellfish Poisoning (ASP) and can cause illness or death in humans.
The CDPH warnings against eating sport-harvested bivalve shellfish from Del Norte County and sport-harvested razor clams from Del Norte and Humboldt counties remain in effect, as does the statewide annual quarantine on sport-harvested mussels. The annual quarantine applies to all species of mussels harvested along the California coast, as well as all bays and estuaries, and will continue through at least October 31.
This warning does not apply to commercially sold clams, mussels, scallops or oysters from approved sources. State law permits only state-certified commercial shellfish harvesters or dealers to sell these products. Shellfish sold by certified harvesters and dealers are subject to frequent mandatory testing to monitor for toxins.
Symptoms of domoic acid poisoning can occur within 30 minutes to 24 hours after eating toxic seafood. In mild cases, symptoms may include vomiting, diarrhea, abdominal cramps, headache and dizziness. These symptoms disappear within several days. In severe cases, the victim may experience trouble breathing, confusion, disorientation, cardiovascular instability, seizures, excessive bronchial secretions, permanent loss of short-term memory, coma or death. No cases of human poisoning from domoic acid are known to have occurred in California.