The annual California Department of Public Health (CDPH) shellfish safety warning is set to take effect on May 1. This warning, which will remain in place until October 31, advises consumers not to consume sport-harvested mussels along the state’s coastline. However, commercially harvested shellfish are exempt from this warning as they undergo strict testing requirements and are certified by the CDPH. Therefore, mussels available for commercial consumption are safe to eat.

The aim of this annual mussel warning is to prevent two illnesses – paralytic shellfish poisoning (PSP) and domoic acid poisoning, also known as amnesic shellfish poisoning. These diseases are caused by naturally occurring toxins that can be present in shellfish such as mussels and clams. Cooking does not eliminate these toxins, and early symptoms of poisoning can include tingling of the lips and tongue followed by more severe symptoms like loss of balance, slurred speech, and difficulty swallowing.

In severe cases, poisoning can lead to trouble breathing, confusion, and disorientation requiring immediate medical attention. To reduce health risks during the summer months starting on May 1st, sport harvesters are advised not to consume recreationally harvested mussels. More information about the quarantine PSP and domoic acid poisoning can be found on the CDPH website or by calling the CDPH Biotoxin Information Line at (800) 553-4133. Additionally, Santa Barbara County Public Health Department is providing information on this matter for public safety awareness during this period.