A disturbing image has revealed a toxin has been detected leaking into the air that could cause paralysis and even death.
The dangerous toxin, which is released from pond scum known as algal bloom that sits on still water across the world, is known as anatoxin-a (ATX), or the "Very Fast Death Factor".
A study published in scientific journal Lake and Reservoir Management said the toxin had been detected in the air near a pond in the US state of Massachusetts for the very first time, and could be lethal to wildlife and humans.
According to the study, ATX can lead to a number of horrific symptoms if breathed in by humans, including paralysis.
"ATX can cause a range of symptoms at acute doses, including loss of coordination, muscular twitching and respiratory paralysis, and has been linked to the deaths of livestock, waterfowl and dogs from drinking contaminated water," according to the study.
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Researchers believe the deadly toxin is produced when fertiliser run-off enters the water source from nearby fields or wastewater that has been treated improperly.
The study suggests if it mixes with pond scum in high water temperatures it can have dire consequences.
"ATX is one of the most dangerous cyanotoxins produced by harmful algal blooms, which are becoming more predominant in lakes and ponds worldwide due to global warming and climate change," Dr James Sutherland, from the Nantucket Land Council and lead author of the study, said in a statement.
Stern warning to people across the world
Researchers are still unsure how the deadly toxin came to be leaked into the air from the pond and are speculating it could have been within small water droplets attached to aerosol particles or inside cyanobacteria blown into the air.
Dr Sutherland suspected the toxin leaks into the air under certain environmental conditions as the detection in the air occurred on a foggy September day after a windy night.
Researchers believe the ATX had been blown off the surface of the water by strong winds and then protected by the fog.
"The fact that there is exposure is clearly a cause of concern and requires further research," the study said.
While the toxin has only been detected in the air so far at one pond, the researchers are urging people across the world to be cautious when around still water with algal blooms.
"People often recreate around these lakes and ponds with algal blooms without any awareness of the potential problems," Dr Sutherland said in the statement.
"Direct contact or inhalation of these cyanotoxins can present health risks for individuals, and we have reported a potential human health exposure not previously examined."