The ecological phenomenon, known as Florida red tide, can be harmful for people with asthma. Florida red tides, an annual event in areas along the Gulf of Mexico, are blooms of the ocean organism, Karenia brevis (K brevis), that are concentrated along shorelines and produce highly potent aerosolized toxins. New research reported in the January issue of CHEST, the peer-reviewed journal of the American College of Chest Physicians (ACCP), shows that Florida red tide toxins (known as brevetoxins) can impact respiratory function and increase respiratory symptoms in patients with asthma.
“In the normal population, inhaled aerosolized red tide toxins can lead to eye irritation, rhinorrhea, nonproductive cough, and wheezing. However, these symptoms usually subside after leaving beach areas,” said study author Lora E. Fleming, MD, PhD, University of Miami Rosenstiel School of Marine and Atmospheric Science, Miami, FL. “Our study shows that Florida red tide toxins may have a greater impact on patients with asthma, who experienced respiratory problems and decreased lung function after just one hour of beach exposure to the toxins.”
Dr. Fleming and a team of researchers from seven academic, environmental, and government institutions evaluated the exposures and effects of aerosolized Florida red tide brevetoxins in 97 subjects with asthma. Participants, who were all residents of Sarasota, FL, spent at least one hour at Sarasota?s Siesta Beach during active K brevis bloom (exposure period) and during a period when there was no bloom (nonexposure period). Detailed baseline information was collected, and all participants underwent pre- and post-beach evaluations, including medical history questionnaires, nasal swab sampling, and lung function testing (spirometry). Each participant also carried a personal air monitor while at the beach. Throughout exposure and nonexposure periods, researchers collected water and air samples and monitored air temperature, relative humidity, and wind speed and direction.