Household chemicals cause as much smog as cars now?

Nature gets a little provocative with research that seems to show that as much air pollution comes from our houses as our cars:

Volatile organic compounds contribute to the formation of ozone and the fine airborne particulates that make up smog, which is linked to health problems from asthma to heart disease. Cars and trucks have historically pumped out most of these compounds, along with other pollutants such as nitrogen oxides. But significant levels of volatile organic compounds also escape from household and commercial products, according to a study published on 15 February in Science.

“The things I use in the morning to get ready for work are comparable to emissions that come out of the tailpipe of my car,” says Brian McDonald, an air-pollution researcher at the US National Oceanic and Atmospheric Administration (NOAA) in Boulder, Colorado, who led the work. “I think that’s what surprises a lot of people.”

The team drew on information compiled by the California Air Resources Board on the chemical composition of everyday items such as household cleaners, dry-cleaning fluids, nail-varnish removers and printing inks. They then analysed their air samples for a wide range of compounds that probably originated in these products. The researchers also estimated the proportion of volatile organic compounds from products such as soaps and cleaners that ends up in the air, as opposed to being washed down the drain.

The offending chemical products differ from vehicle emissions in an important way, says study co-author Jessica Gilman, a chemist at NOAA in Boulder. “They’re designed to evaporate,” she says. Once in the air, the compounds can escape outdoors, where a series of reactions transforms them into ozone and fine particles, she says.

You can check out the study at Science here.