PITTSBURGH -- Carnegie Mellon University researchers say government officials need to adopt new ways of measuring and regulating the fine particles of smoke and soot so endemic to serious health problems and the global warming crisis.
In a March 2 article published in the journal Science, professors Allen L. Robinson and Neil M. Donahue report a new conceptual model for how microscopic particles behave in the atmosphere that raises new questions about current regulations.
The research found new chemical processes that occur after soot and gaseous pollutants are emitted from cars and trucks, changing the chemical and physical properties of the soot particles and creating new particulate matter. These new particles are potentially more toxic and may have a stronger influence on cloud formation that can alter the global climate.
"One of our key findings is that this chemical processing leads to more particulate matter in the air, meaning that regulators are likely underestimating how sources such as cars and trucks contribute to pollution," said Robinson, an associate professor of mechanical engineering and engineering and public policy. "We need to take a holistic approach to regulating these sources that account for all emissions." Accounting for these new processes improves the predictions of the models federal and state governments use to develop regulations.
"A second important finding is that the properties of this new particulate matter are different than we previously thought and potentially more toxic," added Donahue, an associate professor of chemical engineering and chemistry.
Particulate matter poses a serious health problem. Fifty thousand Americans are thought to die prematurely each year due to particle exposure, and almost 70 million Americans live in areas that violate the federal standard. That standard was strengthened in September after scientists, armed with years of studies showing that these particles can damag
Contact: Chriss Swaney
Carnegie Mellon University