The California Department of Public Health (CDPH) is adding sport-harvested clams and whole scallops to the list of Del Norte County bivalve shellfish that consumers should avoid. This is in addition to the annual mussel quarantine that was extended October 31 for both Del Norte and Humboldt counties.
Dangerous levels of paralytic shellfish poisoning (PSP) toxins have been detected in mussels from this region; clams and scallops may also pose a health risk. The naturally occurring PSP toxins can cause illness or death in humans.
This warning does not apply to commercially sold clams, mussels, scallops or oysters from approved sources. State law only permits state-certified commercial shellfish harvesters or dealers to sell these products. Shellfish sold by certified harvesters and dealers are subject to frequent mandatory testing.
PSP toxins affect the central nervous system, producing a tingling around the mouth and fingertips within a few minutes to a few hours after eating toxic shellfish. These symptoms are typically followed by loss of balance, lack of muscular coordination, slurred speech and difficulty swallowing. In severe poisonings, complete muscular paralysis and death from asphyxiation can occur. Cooking does not destroy the toxin.
To receive updated information about shellfish poisoning and quarantines, call CDPH’s toll-free “Shellfish Information Line” at (800) 553-4133.
For additional information, please visit the CDPH Marine Biotoxins Frequently Asked Questions (FAQ) Web page.
