California health officials Tuesday warned people to avoid eating Dungeness and Rock crabs that contain dangerous levels of a neurotoxin linked to a massive algae bloom off the West Coast.

High levels of domoic acid were found in crabs from the Oregon border to the southern Santa Barbara County line, the Department of Public Health reported.

In severe poisoning cases, the neurotoxin can cause seizures, coma or death.

It was unclear how much of an effect the health warning might have on California crabbing, which is estimated to bring in at least $60 million commercially, said Jordan Traverso, a spokeswoman at the California Department of Fish and Wildlife.


Rock crabs are caught year-round. Recreational fishing for Dungeness crabs begins Saturday and commercial fishing starts later this month.

“The conditions that support the growth of this plant are impossible to predict, and it is unknown when the levels found in crab will subside,” a health department statement said. “The health advisory will be lifted once the levels are no longer above acceptable levels.”

The toxin is linked to a vast algae bloom off the West Coast -- which has seen unusually warm ocean temperatures.

Such blooms are cyclical, but this summer, surveyors aboard a National Oceanic and Atmospheric Administration research vessel said the algae bloom was one of the largest ever observed on the West Coast.


The toxin has affected shellfish and sickened or killed seabirds, seals, dolphins and whales throughout the region.

Oregon state officials issued an advisory Tuesday for all recreationally caught crab along the southern Oregon coast, from south of Coos Bay to California. Officials warned people to remove the viscera, or guts, before eating crab meat.

Last month, Washington shellfish managers postponed the fall start of razor clam digging on ocean beaches, and all razor clamming remains closed along the Oregon coast because of high level of domoic acid.