Sacramento – The California Department of Public Health (CDPH) is advising consumers not to eat sport-harvested mussels, clams, scallops, or oysters from Monterey County.   

Dangerous levels of domoic acid, also referred to as amnesic shellfish poisoning, have been detected in mussels from Monterey County. The naturally occurring domoic acid toxin can cause illness or death in humans. Cooking does not destroy the toxin. 

This shellfish safety notification is in addition to the annual mussel quarantine. The annual mussel quarantine prohibits the sport-harvest of mussels for human consumption along the California coast, as well as all bays and estuaries, and will continue through at least October 31. 

Symptoms of amnesic shellfish 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.  

This warning does not apply to commercially sold mussels, clams, scallops, and 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 toxins. 

You can receive the most current information on shellfish advisories and quarantines by calling CDPH’s toll-free Shellfish Information Line at (800) 553-4133 or by viewing the recreational bivalve shellfish advisory interactive map. For additional information, please visit the CDPH Marine Biotoxin Monitoring web page. ​ ​​