SACRAMENTO (April 27, 2007) – Consumers should not eat sport-harvested species of bivalve (two-shelled) shellfish, sardines and anchovies or the organs, or viscera, of sport-harvested or commercially sold lobster or crab taken from the coast of Los Angeles, Orange, San Luis Obispo, Santa Barbara and Ventura counties because they may be contaminated with domoic acid, a naturally occurring toxin that can cause human illness, State Public Health Officer Dr. Mark Horton warned today.  Dogs, cats, birds and other household pets are also susceptible to domoic acid poisoning and should not be fed these products.

The California Department of Health Services (CDHS) has detected elevated levels of domoic acid in sardines and mussels from the coast in these five counties.  Other seafood, including bivalve shellfish such as oysters, clams and scallops and the viscera of anchovies, crab and lobster, have not been tested, but could also contain dangerous levels of toxin.  Crab viscera is commonly known as “crab butter” and lobster viscera is called “tomally.”

This advisory is in addition to the current quarantine on the sport-harvesting of mussels along the entire California coastline that took effect April 20.

Domoic acid was first identified in 1991 in samples of mussels, razor clams and other seafood at several locations along the Pacific Coast, including California.  No known cases of human poisoning from this toxin are known to have occurred in California.  CDHS includes testing of domoic acid and other marine toxins in its biotoxin monitoring program.

Symptoms of domoic acid poisoning include vomiting, abdominal cramps, diarrhea, headache, disorientation, seizures and loss of short-term memory.  Severe cases may be fatal or result in permanent short-term memory.  Older individuals and individuals with impaired kidney function are more vulnerable to the toxic effects of domoic acid.

This warning does not apply to commercially caught bivalve shellfish, which are sold by certified harvesters and dealers and subject to frequent mandatory testing.  State law prohibits the sale or offering for sale for human consumption of any clams, mussels, scallops or oysters, except by state-certified commercial shellfish harvesters or dealers.  Shellfish sold by certified harvesters and dealers are subject to frequent mandatory testing.

For more information, consumers can call CDHS’ toll-free “Shellfish Information Line,” which includes updates on shellfish biotoxins and quarantines, at 1-800-553-4133.

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