Researchers from Florida Atlantic University fear a pathogen could be breeding amid the rising levels of seaweed known as sargassum found washing up on some Florida beaches.
Masses of the sargassum seaweed have grown larger in recent years. This year, the seaweed bloom reached record size, and experts said “major beaching events are inevitable.”
“It impacts tourism, it impacts some of the health of some people living by the beaches,” said Dr. Frank Muller-Kager, an oceanographer at the University of South Florida.
In newly-released research, scientists expressed a new concern: the increased presence of plastics in our waters, plus blooming sargassumn, could provide a breeding ground for vibrio, a bacteria found in oceans and other waterways.
Vibrio bacteria “are the dominant cause of death in humans from the marine environment,” explains a summary of the FAU findings. “Vibrio vulnificus, one of more than 100 species of Vibrio, sometimes referred to as flesh-eating bacteria, can cause life-threatening foodborne illnesses from seafood consumption as well as disease and death from open wound infections.”
The Centers for Disease Control and Prevention explain a person can become infected with this type of vibrio bacteria through an open wound, or by eating raw oysters and other undercooked seafood.
“Many people with Vibrio vulnificus infection require intensive care or limb amputations, and about 1 in 5 people with this infection die, sometimes within a day or two of becoming ill,” warns the CDC.
Now, researchers at FAU are concerned the bacteria is adapting to our oceans and waterways that are increasingly filled with micro-plastics.
“Our lab work showed that these Vibrio are extremely aggressive and can seek out and stick to plastic within minutes. We also found that there are attachment factors that microbes use to stick to plastics, and it is the same kind of mechanism that pathogens use,” said Tracy Mincer, Ph.D., one of the lead authors on the study.
The researchers also say there’s some data showing sargassum that has washed up on beaches appears to “harbor high amounts of Vibrio bacteria.”
The trifecta “creates the perfect ‘pathogen storm’ that has implications for both marine life and public health,” according to a summary of the FAU findings.
Muller-Kager hopes it will encourage people to think more carefully about how they interact with their environment.
“I think the most important thing for people is to look out, open your eyes, and understand what you’re seeing around you in terms of nature and how we fit into it. We depend on it, if we take care of it, we can make it better for ourselves,” he added.
Public health experts advise staying away from sargassum if you see it washing up on beaches. When the seaweed comes on land it starts to rot, letting off hydrogen sulfide and smelling like rotten eggs, explains the Florida Department of Health. It can irritate people’s eyes, nose and throat, and trigger breathing issues for people with asthma.
“Sargassum is also known to often contain heavy metals that can be toxic to humans and animals,” NOAA explains.
Brief exposure isn’t enough to make people sick, but prolonged exposure — especially for those with respiratory issues — can be dangerous, scientists say.
Scientists estimate there’s more than 10 million metric tons of sargassum in the belt this year. Rick Lumpkin, director of the Physical Oceanography Division at NOAA, called it “one of the strongest years, but not the strongest” since scientists began closely observing the biomass via satellite imagery in 2011.