AUSTIN—Cars are no longer the top contributor to urban air pollution. That’s the conclusion of a new study presented here at the annual meeting of AAAS, which publishes Science, that finds pesticides, paints, adhesives, and other consumer and industrial products add about as much to air pollution as transportation does. For the new work, researchers examined volatile organic compounds (VOCs). VOCs react with air to create ozone and, separately, produce fine particulate matter, which contributes to haze. Both of these air pollutants are health hazards and contribute to respiratory diseases, particularly in urban areas where emissions tend to be highest. Emissions from cars and other automobiles have long been considered the major contributor to these kinds of air pollutants. But the new work, which examined the chemical productions statistics from industrial and government agencies, found pesticides, coatings, inks, adhesives, and personal care products such as perfumes produce more than double the emissions of cars. That means U.S. inventories underestimate VOC emissions from these products by as much as a factor of three while overestimating car VOC emissions by 40%, researchers also report today in Science. Because most people use the products that make VOCs indoors, the researchers also compared emissions from residential and commercial buildings to outdoor measurements in Los Angeles, California. They found the concentration of emission compounds indoors was seven times higher than in ambient air. That means air pollution is increasingly from consumer and industrial products rather than from the transportation sector. These products are used indoors where people spend most of their time, which means their use poses a health risk that requires updated regulations, the researchers say.
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