Red Tide Effects

Aerosols from red tides can produce respiratory ailments, such as coughing, sneezing or tearing. This occurs when Karenia brevis is present along the coast and the winds blow its toxic aerosol on shore.  These effects are generally temporary and should vanish within a few hours of leaving the beach, thus ending the exposure.  Studies show that people with severe respiratory conditions (such as emphysema or asthma) should be especially careful.  If you do go near the beach, be sure to have your short acting inhaler with you at all times.  If you experience uncomfortable symptoms, leave the beach and surrounding area immediately.

Studies currently investigating are if there are long-term effects from inhaling Karenia brevis toxins.  However, no studies have been done to determine if there are long-term consequences from inhaling potent neurotoxins from algae.

To find out what the respiratory conditions are at your favorite beach, check the beach forecast.

Yes, swimming is safe for most people.  However, skin irritation and burning eyes has been reported by some people.  As with respiratory irritation, common sense is important.  If you have particularly sensitive skin that is easily irritated, avoid red tide water.  If you experience skin irritation while swimming, leave the water and thoroughly rinse off with fresh water.  Swimming near dead fish is not recommended, as they can be associated with harmful bacteria.

Commercially caught seafood (including seafood at local restaurants and grocery stores) is safe to eat because it is closely monitored for Karenia brevis toxins.  The state of Florida closes shellfish beds in red tide areas quickly and will not re-open them until the shellfish are safe to eat.   

For recreationally caught seafood, it is important to follow a few guidelines.  Finfish are safe to eat if they are caught live and filleted.  Crabs and shrimp are also okay to eat because the toxins are not absorbed into the edible tissues of these animals.  It is not safe to eat bivalves (clams, mussels, or oysters) from areas with red tide.  To check the status of shellfish beds, check the Florida Department of Agriculture and Consumer Services.  Cooking does not destroy red tide toxins!

Do not eat distressed or dead animals, regardless of whether red tide is in the area. 

Consumption of shellfish that are contaminated by K. brevis toxins can cause Neurotoxic Shellfish Poisoning (NSP).  NSP symptoms usually appear within a couple of hours of eating contaminated shellfish and last a few days.  Symptoms can include: gastro-intestinal distress, reversal of hot and cold sensations, headache, chills, and generalized muscle weakness.