Sampling of mussels has confirmed that shellfish-borne paralytic shellfish poisoning (PSP) toxins remain at dangerous levels for these two counties, but are at safe or undetectable levels at all other areas of the California coast.
The annual mussel quarantine is issued for the entire California coastline usually from May 1 through October 31 and is intended to protect the public from PSP and amnesic shellfish poisoning (ASP). The quarantine applies only to sport-harvested mussels. Commercially harvested shellfish are not included in the quarantine as other steps are taken to ensure shellfish entering the marketplace are free of toxins.
PSP is a form of nervous system poisoning. Concentrated levels of the PSP toxins can develop in mussels and other bivalve shellfish when they feed on certain naturally occurring marine plankton.
ASP, also known as domoic acid poisoning (DAP), has been linked to another type of marine plankton consumed by filter-feeding animals, like bivalve shellfish. No known cases of ASP have occurred in California this season. Domoic acid has been linked to numerous poisonings of marine mammals along the Pacific Coast and was originally linked to hundreds of illnesses and several deaths in Eastern Canada.
CDPH’s shellfish sampling and testing programs issue warnings or quarantines when needed. Local health departments, various state and federal agencies and others participate in the monitoring program.
Consumers can receive updated information about shellfish poisoning by calling the Shellfish Information Line at (800) 553-4133. More information about the quarantine, PSP and DAP can be found on the Mussel Quarantine Frequently Asked Questions (FAQ) Web page, click here.