Authorities from the California Department of Public Health released a warning Friday that consumers should avoid eating rock crabs from Half Moon Bay and bivalve shellfish and crabs from Monterey Bay.
The warning applies to state waters in the Central Coast, according to health officials, pointing to an area roughly between Cypress Point and Pigeon Point in Monterey County.
Rock crabs caught at Half Moon Bay showed domoic acid levels more than ten times the amount that requires immediate action.
Parts of Half Moon Bay, north of Pigeon Point, are still covered by a fishery closure. But the domoic acid levels in the crabs and shellfish have raised concerns throughout the entire region.
Only rock crabs and shellfish caught recreationally or commercially are included. Seafood sold via dealers and harvesters who are state-certified are excluded from the warning, as their products undergo toxin testing frequently.
Poisoning from the toxin can occur within 30 minutes to 24 hours after ingesting seafood containing domoic acid. Mild domoic acid poisoning symptoms include vomiting, diarrhea, abdominal cramps, headaches, and dizziness. These usually disappear within a few days, health officials say.
In severe cases, symptoms include difficulty breathing, confusion, disorientation, seizures, excessive bronchial secretions, irregular heartbeats, loss of short-term memory and in the worst scenarios, comas, and death.
So far, there have been no reported cases of domoic acid poisoning in the area, health authorities note but strongly caution consumers for prevention purposes.
High domoic acid levels were responsible for the closure of last season’s Dungeness crab fishing industry, causing around $48 million in losses, state officials say. The same domoic acid likewise negatively affected rock crab fishing earlier in the year.
The health department will continue working with the state’s Department of Fish and Wildlife to collect samples of toxic seafood until domoic acid levels have normalized.