San Diego County health officials are warning residents not to eat recreationally harvested shellfish unless it came from a state-certified commercial harvester or dealer, according to Patch and county health officials.

The annual California Department of Public Health quarantine on sport-harvested mussels began May 1 and remains in effect through Oct. 31 along the California coast, including bays and estuaries. The warning also applies to clams, scallops and oysters that were not purchased through approved commercial channels.

Health officials said toxins such as domoic acid and saxitoxin can build up in shellfish during warmer months. Symptoms can begin within 30 minutes to 24 hours and may include vomiting, diarrhea, dizziness, confusion, seizures or worse in severe cases.

For Santee residents, the advisory is most relevant during beach trips, tidepool visits and summer gatherings where recreational harvesting might be tempting. Store-bought and restaurant shellfish remain subject to commercial testing and are not part of the warning.

More information is available from San Diego County environmental health officials and the California Department of Public Health Shellfish Information Line at 800-553-4133.