Even the tiniest of the particulate matter in the air can cause big adverse impacts. Especially dense urban areas with their vehicle emissions in combination with urban heat provide excellent conditions for chemical reactions. While some of the pollutants are emitted directly into the air, others are formed within the atmosphere as a result of gaseous oxidation. This chemical alteration of pollutants is part of the research work of the MIT associate professor Jesse Kroll.
Don’t underestimate the chemical alteration of pollutants
Specialized in the fields of civil, environmental and chemical engineering, he has based his research on investigating the role of organic compounds in the air. They consist of combustible substances and natural emissions from plants. The diameter of the emitted particles is less than a micron. But when we talk about the environmental effects, it is quite simply wrong to say that they are negligible.
Once in the atmosphere, chemical compounds are able to form 10 or 100 more chemical products
It is not just the health hazard. Moreover, they also play a big role in climate change. “If you inhale them, they can cause adverse health effects, and they also can affect the Earth’s climate by affecting the amount of sunlight that comes through,” Kroll says.
He goes on to explain further, “It’s not just that there are a lot of different compounds. Once in the atmosphere, they oxidize, and each one can form 10 or 100 more chemical products, which in turn can form many others. It’s a deeply complex system, so from a chemist’s perspective, it’s a really fascinating field.”
Chemical alteration of pollutants takes place with many different reactions and a variety of molecules
However, Kroll is not only doing researches with reactors or tubes in his laboratory, where he performs exact measurements. Atmospheric investigations on the ground and so-called multi-institution field studies are also part of his research. Additionally, he and his students are participating in large-scale lab projects – huge controlled environments where they simulate wildfires.
Kroll, a native of Austin, Texas, developed a liking for chemistry when he was in high school. He completed his Ph.D. in this field at Harvard after graduating from there with a major in chemistry, earth, and planetary sciences. He went on to take up a postdoc position at Caltech and joined MIT faculty in 2009.
According to him, the organic aerosols play a major role in adversely affecting the atmosphere. He says, “there are so many different reactions and so many different molecules involved, we can’t hope to measure them all. The ultimate objective is to understand what policies could help, and what changes policymakers could make to minimize the negative health and climate effects of particulate pollution.”