Florida Red Tides: Environmental Exposures and Human Health Effects
Lora Fleming, School of Medicine, University of Miami
3 Feb 2006
The marine and freshwater toxins are potent natural toxins elaborated by phytoplankton and associated with acute and chronic disease in human and other animals. Florida red tide is associated with blooms of the dinoflagellate, Karenia brevis, and production of potent neurotoxins, brevetoxins. In addition to health effects associated with the ingestion of contaminated shellfish (i.e., neurotoxic shellfish poisoning), there have been multiple anecdotal reports of respiratory irritation and possibly immunologic effects associated with inhalation of aerosolized Florida Red Tides. To investigate human health effects from environmental exposure to red tide toxins, we have formed an inter-disciplinary team of scientists. When a red tide moves onshore, the team rapidly assembles to collect environmental samples (air, water, particulates) and epidemiologic data (pre/post-exposure questionnaires, pulmonary function tests, and personal monitoring). To assess more long-term effects, the epidemiologic studies involve sensitive populations (including asthmatics) who live in endemic areas. Acute and chronic respiratory effects of red tides and brevetoxin are also evaluated in rat and asthmatic sheep models, as well as toxin exploration (including natural antagonists). These models are being used to refine and validate biomarkers of brevetoxin exposure and effect, as well as explore the pathophysiology of health effects from aerosolized brevetoxins. This inter-disciplinary scientific team is exploring acute and chronic exposures and health effects, as well as prevention and treatment, of aerosolized Florida Red Tides in animal models and various human populations.