Modern diesel cars emit less pollution generally than cars that run on gasoline, says a new six-nation study published today in Scientific Reports whose groundwork was laid in part by an American chemist now working at Université de Montréal.
And since diesel is so much cleaner than before, environmental regulators should increasingly shift their focus to dirtier gasoline-powered cars and other sources of air pollution, says the UdeM scientist, Patrick Hayes.
“Diesel has a bad reputation because you can see the pollution, but it’s actually the invisible pollution that comes from gasoline in cars that’s worse,” said Hayes, 36, an assistant professor at UdeM.
“The next step should be to focus on gasoline or removing old diesel vehicles from the road. Modern diesel vehicles have adopted new standards and are now very clean, so attention needs to now turn to regulating on-road and off-road gasoline engines more. That’s really the next target.”
The study, led by researchers in Switzerland and Norway with help from Hayes and colleagues in Italy, France and the U.S., looked at carbonaceous particulate matter (PM) emitted from the tailpipes of cars.
Carbonaceous PM is made up of black carbon, primary organic aerosol (POA) and, especially, secondary organic aerosol (SOA), which is known to contain harmful reactive oxygen species and can damage lung tissue.