New chemicals may have a longer-lasting impact on the environment. (File)
Paris:
Remnants of industrial chemicals in the air have the potential to transform into new substances that are more toxic and persistent than the original pollution levels, according to a global study published Wednesday.
Using samples collected around the world, research published in the journal Nature shows that these previously unidentified products are present in the atmospheres of 18 major cities including Lagos, New York, Tokyo and Warsaw.
Regulatory guidelines such as those listed in the Stockholm Convention assess the hazard levels of various chemical pollutants based on how long they remain in the environment, how toxic they are, and how degree they contaminate living organisms.
However, the study notes, this approach is limited to the list of known substances and does not take into account how they might change as they decompose.
The study proposes a new framework that uses laboratory tests and computer simulations to predict what chemicals are released when products interact with the air and how toxic they are.
Study lead author John Liggio, a research scientist with Environment Canada, worked with a team to test a framework for nine of the most commonly found flame retardant chemicals in the atmosphere.
“They are chemicals that are added to various materials to delay the outbreak of a fire,” Liggio told AFP.
In a laboratory, they observed how these chemicals changed over time when exposed to an oxidant in the air and found that they produced 186 different substances.
Comparing these new substances with field samples, they found 19 substances derived from five of the most common flame retardants. None of the 19 have ever been identified in ambient air before.
The team then used computer simulations to evaluate the durability, toxicity and bioaccumulation of the derived chemicals.
They found that the new chemicals could have a longer-lasting impact on the environment and could be more toxic than their parent chemicals – in some cases, 10 times more.
The framework should provide a new avenue to include transformative products in routine air monitoring programs, and favor high-concern variable products for scrutiny, the study said. than”.
While the study looked at nine common chemical pollutants and their 19 sub-chemicals found in urban air samples, Liggio says these results are just the tip of the iceberg.
“There could be thousands of different chemicals in existence,” he said, adding that future tests will look at tire chemicals, antioxidants and other plastic additives. .
Another goal is to test the toxicity of pollutants in real-world studies, beyond the computer model used for this study.
(This story has not been edited by NDTV staff and was automatically generated from the feed provided.)
