Florida has experienced numerous harmful algal blooms in recent years, including blue-green algae and their toxins in 2016 and 2018. Despite their intensity and frequency, there is scant data on human exposure to these blooms and concentrations of the toxins they produce in tissues of exposed individuals. The most common routes of human exposure to these toxins include direct contact, ingestion and inhalation. Little is known about airborne exposure to these toxins in recreationally and occupationally exposed humans.
A study led by researchers at Florida Atlantic University’s Harbor Branch Oceanographic Institute in collaboration with FAU’s Christine E. Lynn College of Nursing and Colorado State University, was recently published in the journal Harmful Algae . The results provide evidence of aerosol exposure to microcystins among coastal residents.
Researchers detected microcystin, the main class of cyanotoxins produced by blue-green algae species, in the nasal passages of 95 percent of the participants. Some of these individuals reported no direct contact with impacted water. Therefore, these findings may be due to the aerosolization of cyanobacteria and transport in the air as has previously been hypothesized.
“Aerosolized cyanotoxins represent an important potential route of exposure and should be included in risk assessments for human populations,” said Adam Schaefer, M.P.H., lead author and an epidemiologist at FAU’s Harbor Branch. “Our study represents an essential first step in assessing and mitigating the potentially harmful effects of cyanobacteria blooms. We have a lot of unanswered questions to address regarding absorption of toxins, the minimum safe distance for persons from blooms, and potential health effects of exposure.”
Read more at Florida Atlantic University
Image: Nancy Harris, D.N.P., an assistant professor with FAU's Christine E. Lynn College of Nursing (left) speaks with a study participant as Adam Schaefer, M.P.H., lead author and an epidemiologist at FAU's Harbor Branch, reviews the chart. (Credit: Florida Atlantic University)