The current health advisory has been extended to include Humboldt and Del Norte counties. The California Department of Health advises consumers not to eat recreationally harvested bivalve shellfish (mussels and clams) from Humboldt or Del Norte counties. Only the white meat (adductor muscle) of scallops should be consumed and the viscera (internal organs) should be discarded.
Dangerous levels of domoic acid have been detected in mussel and razor clam samples and may be present in the other species that have not yet been tested. This toxin, also known as Amnesic Shellfish Poisoning (ASP), can cause illness or death in humans. No cases of human poisoning from domoic acid are known to have occurred in California.
This advisory extends the one made by CDPH officials in June, warning consumers not to eat recreationally harvested mussels and clams, commercially or recreationally caught anchovy and sardines, or the internal organs of commercially or recreationally caught crab taken from Monterey and Santa Cruz counties (this advisory remain in effect).
CDPH is continuing to collect a variety of molluscan bivalve shellfish, fin fish and crab samples from these areas to monitor the level of domoic acid.
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.View Advisory
To receive updated information about shellfish poisoning and quarantines, call CDPH’s toll-free “Shellfish Information Line” at (800) 553-4133. For additional information visit CDPH’s Biotoxin Monitoring web page
CeNCOOS supports the monitoring of potentially toxic algal species at three sites and the analysis of collected samples. These activities directly contribute to the CDPH's biotoxin monitoring program. You can find out more on CeNCOOS's work in this area on our Algal Blooms page, which also includes information on our joint project with UCSC researches to forecast harmful algal blooms.