Inland transport of aerosolized Florida red tide toxins

Abstract

Florida red tides, an annual event off the west coast of Florida, are caused by the toxic dinoflagellate, Karenia brevis. K. brevis produces a suite of potent neurotoxins, brevetoxins, which kill fish, sea birds, and marine mammals, as well as sickening humans who consume contaminated shellfish. These toxins become part of the marine aerosol, and can also be inhaled by humans and other animals. Recent studies have demonstrated a significant increase in symptoms and decrease lung function in asthmatics after only one hour of beach exposure during an onshore Florida red tide bloom. This study constructed a transect line placing high volume air samplers to measure brevetoxins at sites beginning at the beach, moving approximately 6.4 km inland. One non-exposure and 2 exposure studies, each of 5 days duration, were conducted. No toxins were measured in the air during the non-exposure period. During the 2 exposure periods, the amount of brevetoxins varied considerably by site and by date. Nevertheless, brevetoxins were measured at least 4.2 kilometers from the beach and/or 1.6 km from the coastal shoreline. Therefore, populations sensitive to brevetoxins (such as asthmatics) need to know that leaving the beach may not discontinue their environmental exposure to brevetoxin aerosols.

Establishing the link between <em>Ostreopsis</em> cf.<em>ovata</em> blooms and human health impacts using ecology and epidemiology

“…In particular, landward winds should favour the transport of aerosolized compounds from the seawater to the beach and the nearby inhabited areas, and be involved in the health impacts (Vila et al 2008, Kirkpatrick et al 2010. However, no relevant differences concerning the landward wind component during the two affect periods and the days between them were found (Table 3).…”

“…Multidisciplinary research and monitoring are required to prevent or mitigate adverse health effects from exposure to complex aerosolized biotoxins produced by microalgae. In the case of the Karenia brevis, for outbreaks in the coasts of Florida and Gulf of Mexico (Kirkpatrick et al 2010, 2011) this approach was addressed over several years and allowed progress to be made towards the development of early warning systems. Information about the presence of a Florida red tide is now available from the Gulf of Mexico HAB Forecast (NOAA Harmful Algal Bloom Operational Forecast System, https:// tidesandcurrents.noaa.gov/hab/) in conjunction with a local Beach Condition Reporting System.…”

Karenia: The biology and ecology of a toxic genus

“…Photodegradation (Hardman et al, 2004) and other physical/chemical processes alter the suite of brevetoxin congeners such that a different mix is observed in the air (Pierce et al, 2003Cheng et al, 2005Cheng et al, , 2010. Brevetoxin aerosols can be found at least 1.6 km inland (Kirkpatrick et al, 2010b).…”

Repeated exposure to aerosolized brevetoxin-3 induces prolonged airway hyperresponsiveness and lung inflammation in sheep

“…This level of exposure would be in the lower range of that seen in the field. Thus, the prolonged development of AHR in these animals seen under controlled conditions may help explain reports of prolonged airway symptoms by individuals after a beach red tide exposure (Fleming, 2007;Kirkpatrick, 2006Kirkpatrick, , 2010b.…”