Lora E. Fleming, MD PhD MPH MSc¹, Barbara Kirkpatrick, EdD², Lorraine C. Backer, PhD, MPH³, Judy A. Bean, PhD⁴, Adam Wanner, MD⁵, Dana Dalpra, BS², Robert Tamer, BS⁶, Julia Zaias, DVM⁷, Yung-Sung Cheng, PhD⁸, Richard H. Pierce, PhD², Jerome Naar, PhD⁹, William Abraham, PhD⁵, Richard Clark, MS¹⁰, Yue Zhou, PhD⁸, Michael Henry, MS², David Johnson, MD¹¹, Gayl Van De Bogart, BA¹², Gregory D. Bossart, VMD, PhD¹³, Mark Harrington¹⁴, and Daniel G. Baden, PhD¹⁵. (1) Epidemiology & Public Health, University of Miami School of Medicine, 1801 NW 9th Avenue Suite 200, Miami, FL 33149, 305-243-5912, lfleming@med.miami.edu, (2) Ecotoxicology and Human Health, Mote Marine Laboratory, 1600 Ken Thompson Parkway, Sarasota, FL 34236, (3) National Center for Environmental Health, Centers for Disease Control and Prevention, 4770 Buford Highway NE, MS F-46, Chamblee, GA 30341, (4) Biostatics Division, Childrens Hospital of Cincinnati, 3333 Burnet Avenue, Cincinnati, OH 45229, (5) Division of Pulmonary Medicine, University of Miami School of Medicine, PO Box 016069, Miami, FL 33101, (6) School of Medicine, Department of Epidemiology & Public Health, University of Miami, P.O. Box 016069 (R669), Miami, FL 33101, (7) Division of Comparative Pathology, University of Miami School of Medicine, 1600 NW 10th Ave., Room 7101A, Miami, FL 33136, (8) Dosimetry Program, Loveless Respiratory Research Institute, P.O. Box 5890, Albuquerque, NM 87185, (9) Center for Marine Research, 1 Marvin Moss Lane, Wilmington, NC 28409, (10) Environmental Epidemiology, Florida Dept of Public Health, 4052 Bald Cypress Way, Tallahassee, FL 32399, (11) Florida Department of Health, 4052 Bald Cypress Way, Tallahassee, FL 32399, (12) NIEHS Marine and Freshwater Biomedical Sciences Center, University of Miami Rosenstiel School of Marine and Atmospheric Sciences, 4600 Rickenbacker Causeway, Miami, FL 33149, (13) Harbor Branch Oceanographic Institution, 5600 US 1 North, Fort Pierce, FL 34946, (14) Twin Cities Hospital, 2190 HIghway 85 North, Niceville, FL 32578, (15) Center for Marine Science Research, University of North Carolina at Wilmington, 1 Marvin K. Ross Lane, Wilmington, NC 28409

Florida red tides annually occur in the Gulf of Mexico, resulting from blooms of the marine dinoflagellate, Karenia brevis. K. brevis produces highly potent natural polyether toxins, brevetoxins, that activate voltage sensitive sodium channels. In experimental animals, brevetoxins cause significant bronchoconstriction. A study of persons who visited the beach recreationally found significant increase in self-reported respiratory symptoms after exposure to aerosolized Florida red tides. Anecdotal reports indicate that persons with underlying respiratory diseases may be particularly susceptible to adverse health effects from these aerosolized toxins.

Fifty-nine persons with physician-diagnosed asthma were evaluated for 1 hour before and after going to the beach on days with and without Florida red tide. Study participants were evaluated with a brief symptom questionnaire, nose and throat swabs, and NIOSH-approved spirometry. Environmental monitoring, water and air (i.e., K. brevis, brevetoxins and particulate size distribution) sampling, and personal monitoring (for toxins) were performed. Brevetoxin concentrations were measured by LCMS, HPLC, and a newly developed brevetoxin ELISA. Participants were significantly more likely to report respiratory symptoms after Florida red tide exposure. Participants demonstrated small but statistically significant decreases in FEV1, FEF25-75, and PEF after exposure, particularly among those using regular asthma medications. Similar evaluation during non exposure periods did not significantly differ.

This is the first study to show objectively measurable adverse health effects from exposure to aerosolized Florida red tide toxins in persons with asthma. Future studies will examine the possible chronic effects of these toxins among persons with asthma and with other chronic respiratory impairment.

Learning Objectives:

• Describe the known epidemiology of the major diseases in humans and other animals from harmful algal blooms.
• Identify the association between environmental and personel toxin monitoring with human health effects
• Identify the objective human health effects measured in susceptible subpopulations (asthmatics) from exposure to Florida red tide toxins (brevetoxins)

Keywords: Environmental Exposures, Asthma

Related Web page: www.mote.org/niehsredtidestudy/

Presenting author's disclosure statement:
I do not have any significant financial interest/arrangement or affiliation with any organization/institution whose products or services are being discussed in this session.