Face masks protect against aerosolized toxins from algal blooms, study finds

MIAMI—Intense blooms of poisonous algae have gotten frequent occurrences alongside the coast of Florida and elsewhere. Outcomes from a brand new examine led by College of Miami (UM) scientists discovered that sporting the face masks everybody has turn into accustomed to throughout the COVID-19 pandemic could assist defend in opposition to these airborne toxins too.

The UM Rosenstiel College of Marine and Atmospheric Science researchers designed an experiment to grasp how efficient generally out there air conditioner filters and face masks are at filtrating out the toxins emitted throughout dangerous algal bloom occasions.

“We discovered that face masks and air conditioner filters with excessive filter efficiency scores can cut back the chance of publicity by filtering out small, toxin-containing particles,” mentioned the examine’s lead creator Cassandra Gaston, an assistant professor of atmospheric sciences on the UM Rosenstiel College. 

“These filter supplies will also be efficient at filtering out other forms of small particles as effectively,” mentioned Haley Royer, a co-first creator of the examine and Ph.D. scholar on the UM Rosenstiel College’s Division of Atmospheric Sciences. “As everyone knows by now, face masks are important in stopping the transmission of COVID-19 from individual to individual.”

Dangerous algal blooms, sometimes called purple tides and blue-green algae, are exacerbated by nutrient-rich runoff from agriculture and industrial waste that find yourself in waterways. Noxious particles enter the air principally from the breaking of waves, leading to airborne toxins that trigger critical well being issues to people and marine life. Airborne toxins can even have an effect on indoor air high quality significantly for companies and houses close to contaminated waterways.

To conduct the experiment, the researchers created a effervescent gadget to supply airborne toxin-containing particles within the lab by effervescent air into the liquid containing cultures of a toxic-producing blue-green algae, Microcystis aeruginosa. Cutouts of three sorts of face masks and 6 sorts of AC filters bought from dwelling enchancment shops had been positioned in-line with generated particles to find out how effectively the masks and filters blocked particles of various sizes. The researchers used N95, disposable surgical masks and medical-grade, odor-filtering carbon fiber masks. For AC filters, the researchers used filters for window models and central air con models with completely different filter efficiency scores. 

They discovered that AC filters filtered out 20-90% of the airborne particles with particle filtration growing with growing filter efficiency score. Face masks filtered out over 90% of toxin-containing particles. The findings counsel that low-cost, commercially out there face masks and AC filters with excessive filtration effectivity scores can assist keep away from each indoor and outside publicity to dangerous algal bloom toxins within the air.

Dangerous algal blooms are anticipated to turn into extra prevalent worldwide attributable to local weather change and elevated nutrient runoff from a rising human inhabitants.

In response to the researchers, the examine additionally has relevance for the transmission of SARS-CoV-2, the virus liable for the present COVID-19 pandemic. The virus has a median dimension of 60-140 nanometers, which is inside the dimension of particles investigated on this examine.