DISCOVERY BAY, Calif. -- Harmful blue-green algae was detected in in Eastern Contra Costa County's Discovery Bay in samples taken nearly two weeks ago, Contra Costa Health Services' Environmental Health Division said Monday.
Inspectors began sampling the waters of Discovery Bay in mid-June because of multiple complaints, and tests of a sample collected June 29 indicates that the algae is present, according to health officials.
Exposure can result in serious illness or death at higher levels, but typically just causes rash, skin and eye irritation or allergic reactions.
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Still, it may be safe to go in the water, depending on where and whether advisory signs are posted nearby.
"Caution" signs mean do not swim or wade near algae, keep children and dogs away from it in the water or on the shore, do not drink the water or cook with it and don't eat shellfish from the water.
"Warning" signs mean all of the above, but no swimming at all is allowed and fishermen should throw away the guts of any fish caught there, cleaning the fillets with tap or bottled water before cooking.
"Danger" signs mean to stay out of the water until further notice, do not eat fish or shellfish caught in those waters and don't use the water for drinking or cooking. It can't be made safe by boiling or filtering.
Anyone showing signs of blue-green algae poisoning can call the California Poison Center Help Hotline at (800) 222-1222.
Health officials warn of blue-green algae in Discovery Bay