Research has shown that sunlight intensifies the toxicity of smoke by changing its chemical composition. This explains why the air remains harmful days and kilometers after a wildfire.
A new study published in the journal Science Advances revealed that sunlight can turn wildfire smoke into an even more toxic mixture. Under the influence of ultraviolet (UV) radiation, smoke particles change their chemical composition, making them more dangerous to health even after the fire has been put out.
Scientists discovered that solar rays initiate a chain of reactions in which organic compounds in the smoke are converted into aggressive toxic substances. Particularly dangerous are fine particulate matter (PM2.5), which can persist in the atmosphere for weeks and penetrate deep into the human respiratory system.
According to the researchers, this finding explains why the air can remain harmful hundreds of kilometers away from the fire’s epicenter. Exposure to “aged” smoke that has been subjected to solar radiation can cause inflammatory processes and seriously affect the respiratory organs.
Specialists stress that the study’s results should change the approach to assessing the consequences of fires. Air quality monitoring and public health recommendations must now account not only for immediate smoke pollution but also for the chemical changes in particles caused by the sun.
Given the increase in the number and scale of wildfires due to climate change, this data will help develop new strategies for protecting human health and minimizing environmental damage.
