AAAR 37th Annual Conference October 14 - October 18, 2019 Oregon Convention Center Portland, Oregon, USA
Abstract View
The Influence of Temperature on Microcystin Concentration in Bubble-Generated Lake Spray Aerosols
HALEY PLAAS, Kimberly Popendorf, Cassandra Gaston, Larry Brand, University of Miami
Abstract Number: 166 Working Group: Health-Related Aerosols
Abstract Cyanobacteria, or blue-green algae, are planktonic phototrophs that flourish in aquatic environments of every continent. Under eutrophic conditions, cyanobacteria can dominate as dense blooms, negatively impacting water quality. Anthropogenic activity, such as nutrient-loading and climate change, have been demonstrated to intensify cyanobacterial blooms in recent decades. Harmful cyanobacterial blooms (CyanoHABs) are particularly problematic as several genera produce toxins, some including microcystin, a known hepatotoxin. While numerous studies regarding CyanoHABs have investigated the consumption of contaminated food stuffs or water, little research has been conducted to assess the health risks of exposure to cyanotoxins found in aerosols. This study quantified microcystin in bubble-generated lake spray aerosol and investigated the influence of increased water temperatures on the aerosolization of microcystin. Cyanobacteria samples were collected from Lake Okeechobee, Florida during bloom episodes that occurred in the late summer of 2018, then maintained in culture. To simulate the bursting of primary aerosols at the lake-air interface, dilute culture was placed in a bubbling apparatus and resultant aerosols were collected on a filter. Three temperature treatments were chosen to investigate the relationship between water temperature and microcystin concentration in aerosols: room temperature (23C), a typical summer lake surface temperature in Lake Okeechobee (30C), and an elevated lake surface temperature based upon projected climate models (31.5C). Each treatment was run in triplicate on three separate trial days. There is no statistical evidence presented to suggest that temperature plays a role in altering the concentration of aerosolized microcystin compounds. Interestingly, we did not observe a consistent relationship between chlorophyll concentration and microcystin concentration in the water or aerosols. However, this pilot study confirms the ability of microcystin to become airborne and highlights the potential of respiratory exposure to microcystin, along with other cyanotoxins, as a worthy public health concern.