Exposure to Aerosolized Algal Toxins in South Florida Increases Short- and Long-Term Health Risk in Drosophila Model of Aging

Abstract

Harmful algal blooms (HABs) are a rising health and environmental concern in the United States, particularly in South Florida. Skin contact and the ingestion of contaminated water or fish and other seafood have been proven to have severe toxicity to humans in some cases. However, the impact of aerosolized HAB toxins is poorly understood. In particular, knowledge regarding either the immediate or long-term effects of exposure to aerosolized cyanotoxins produced by freshwater blue-green algae does not exist. The aim of this study was to probe the toxicity of aerosolized cyanobacterial blooms using Drosophila melanogaster as an animal model. The exposure of aerosolized HABs at an early age leads to the most severe long-term impact on health and longevity among all age groups. Young groups and old males showed a strong acute response to HAB exposure. In addition, brain morphological analysis using fluorescence imaging reveals significant indications of brain degeneration in females exposed to aerosolized HABs in early or late stages. These results indicate that one-time exposure to aerosolized HAB particles causes a significant health risk, both immediately and in the long-term. Interestingly, age at the time of exposure plays an important role in the specific nature of the impact of aerosol HABs. As BMAA and microcystin have been found to be the significant toxins in cyanobacteria, the concentration of both toxins in the water and aerosols was examined. BMAA and microcystin are consistently detected in HAB waters, although their concentrations do not always correlate with the severity of the health impact, suggesting the potential contribution from additional toxins present in the aerosolized HAB. This study demonstrates, for the first time, the health risk of exposure to aerosolized HAB, and further highlights the critical need and importance of understanding the toxicity of aerosolized cyanobacteria HAB particles and determining the immediate and long-term health impacts of HAB exposure.

Drone-based particle monitoring above two harmful algal blooms (HABs) in the USA

“…5–7 The exposure of HAB associated aerosols has been shown to pose health threats using Drosophila melanogaster as an animal model. 8 Furthermore, HABs appear to be increasing in freshwater bodies around the world. 4,9…”

“…[5][6][7] The exposure of HAB associated aerosols has been shown to pose health threats using Drosophila melanogaster as an animal model. 8 Furthermore, HABs appear to be increasing in freshwater bodies around the world. 4,9 Research is needed to mitigate HABs, including the development of new low-cost and turn-key technologies to capture, detect, and quantify HAB cells and toxins in water and air.…”

Increasing Freshwater Salinity Impacts Aerosolized Bacteria

“…24,26,43 However, recent microbial aerosolization studies focused exclusively on saltwater 24,26,43,46 although aerosolized microorganisms were also detected above freshwater. 47,48 While some studies examined the incorporation of harmful cyanobacteria strains in lake spray aerosols (LSAs), 16,49,50 no previous studies investigated freshwater bacterial community aerosolization from a holistic perspective. Furthermore, the effect of increases in salinity on the aerosolization of freshwater bacterial communities is not well understood.…”

“…More recently, DNA-based approaches, including targeted amplicon sequencing, have become the standard approach for analyzing microbial diversity and community structure . Modern sequence-based community analysis has been recently applied to investigate microbial aerosolization from saltwater, uncovering taxon-specific transfer potential to the aerosol phase. ,, However, recent microbial aerosolization studies focused exclusively on saltwater ,,, although aerosolized microorganisms were also detected above freshwater. , While some studies examined the incorporation of harmful cyanobacteria strains in lake spray aerosols (LSAs), ,, no previous studies investigated freshwater bacterial community aerosolization from a holistic perspective. Furthermore, the effect of increases in salinity on the aerosolization of freshwater bacterial communities is not well understood.…”

Filtration Efficiency of Air Conditioner Filters and Face Masks to Limit Exposure to Aerosolized Algal Toxins

“…experiments with M. aeruginosa: FM2 (disposable surgical mask), AF4 (FPR 10), and AF5 (FPR 4). Two experimental runs using FM2 were performed including an exposure to a model animal, the fruit fly Drosophila melanogaster, which is the subject of a companion paper (Hu et al, 2020).…”