The New Science of Smog

April 8, 2018

Liberals are claiming that the Trump Administration’s plans to roll back the Obama fuel-mileage rules will increase pollution. Perhaps they should read up on the latest scientific evidence about the sources of air pollution.

A recent study in the journal Science traced and measured volatile organic compounds (VOCs) in Los Angeles. In the presence of sunlight, these compounds react with NOx to form ozone and smog. Car exhaust was once a greater relative contributor of VOCs and NOx, but engines are now much cleaner.

Researchers at the University of Colorado found that petroleum-based chemicals such as those found in deodorant, soap, hair spray, household cleaners, pesticides and other commercial products account for about half of VOCs emissions in industrial cities. Gasoline fuel and exhaust make up about 32%.

Environmentalists have long blamed L.A.’s car-driving culture for its smog. But even if most gas-burning vehicles were replaced by electric cars, L.A. would still have a smog problem because...

Read the entire article at The Wall Street Journal (subscription may be required).