The health advisory has been lifted for rock crabs caught in state waters south of 37°11’ N. Latitude, near Pigeon Point in San Mateo County. California Department of Public Health (CDPH) Director and State Public Health Officer Dr. Karen Smith lifted this advisory today due to recent tests showing that traces of domoic acid have declined to low or undetectable levels in crabs caught in the area.
This decision comes after the April 22, 2016 announcement partially lifting the advisory for rock crab caught in state waters south of Latitude 36° 58.72′ N. (near Sand Hill Bluff, approximately nine miles north of Santa Cruz Harbor entrance).
The advisory remains in effect for rock crabs caught in state waters north of Latitude 37° 11′ N. (near Pigeon Point).
CDPH and the Office of Environmental Health Hazard Assessment concur that rock crabs caught in the areas south of 37°11’ N. Latitude are safe to consume. However, as a precaution, consumers are advised not to eat the viscera (internal organs, also known as “butter” or “guts”) of crabs. The viscera usually contain much higher levels of domoic acid than crab body meat. When whole crabs are cooked in liquid, domoic acid may leach from the viscera into the cooking liquid. Water or broth used to cook whole crabs should be discarded and not used to prepare dishes such as sauces, broths, soups or stews (for example, cioppino or gumbo), stocks, roux, dressings or dips.
The best ways to reduce risk are:
- Remove the crab viscera and rinse out the body cavity prior to cooking, or
- Boil or steam whole crabs, instead of frying or broiling, and discard cooking liquids.
Symptoms of domoic acid 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 (a condition known as Amnesic Shellfish Poisoning), coma or death. There have been no reported illnesses associated with this year’s domoic acid event.
Domoic acid accumulation in seafood is a natural occurrence that is related to a “bloom” of a particular single-celled plant. The conditions that support the growth of this plant are impossible to predict. While the bloom that occurred last year has dissipated, it takes a period of time for the organisms feeding on the phytoplankton to eliminate the domoic acid from their bodies.
CDPH will continue to coordinate its efforts with the California Department of Fish and Wildlife and the fishing community to collect rock crab samples from the central and northern California coast until the domoic acid levels have dissipated.
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 Natural Marine Toxins: PSP and Domoic Acid Web page and CDPH’s Domoic Acid health information Web page.