28
Feb
Pesticides and Other Household Chemicals Cause as Much Air Pollution as Vehicles
(Beyond Pesticides, February 27, 2018) As stricter regulations and technological changes begin to 
decrease air pollution from cars and other vehicles, scientists are finding that the use of pesticides and other household chemicals represent an increasing proportion of smog-forming pollution in the U.S. Research published in the journal Science this month indicates that personal care products, cleaning agents, perfumes, paints, printing ink, and pesticides warrant greater attention from regulators for their ability to form toxic fine particulate matter (PM2.5) and tropospheric ozone (O3). “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,” said Brian McDonald, PhD, the study’s lead author and air-pollution researcher at the U.S. National Oceanic and Atmospheric Administration (NOAA) in Boulder, Colorado to Nature. “I think that’s what surprises a lot of people.”
Recognizing a gap in emission data as pollution from cars and other mobile sources of fossil fuel has waned over the past several decades, researchers set out to determine what chemicals were contributing to smog that continues to plague cities throughout the U.S. Using data from energy and chemical manufacturing, combined with roadway pollution and laboratory measurements, scientists created a “mass balance” of all compounds produced by the fossil fuel industry in the U.S. Through this process, it was discovered that emissions of volatile organic chemicals (VOCs), which eventually turn into pollution once released into the air, from household products are “one to two orders of magnitude higher than from vehicle exhaust,” according to the study.
When broken down, scientists attributed between 15 to 42% of VOC emissions to vehicle use, and 39 to 62% to the use of household products, with the remainder being associated with the production of fossil fuels.
The study authors then hypothesize that these chemicals must also be showing up in high concentrations in indoor air. Using a model that took data from measurements of indoor air in commercial and residential buildings, compounds associated with personal care products are roughly seven times higher indoors than amounts found in ambient air.
However, it is when these chemicals make their way outside that they become a significant pollution problem, as they oxidize in the presence of nitrogen oxides to form ozone or nuclearize in the presence of sunlight to form PM2.5. “Say somebody is inside using perfume, cologne,” explains Chris Cappa, PhD, a co-author of the study and researcher at the University of California at Davis to The Washington Post. “That smell eventually dissipates. And the question is, where did it go. And there’s air exchange with the outside. Those odors dissipate because it’s basically getting moved outside. It’s just taking that indoor air and exchanging it with the outdoor air. It’s not that hard to get things from the indoor environment outside.”
To confirm their emissions estimates based on the mass balance data, observed VOC emissions from Los Angeles were compared to their model, and when personal care products were accounted for, authors found the results in line with their assessment.
Chemical dependency in agriculture is also contributing to air pollution. A study published earlier this year in Science Advances by researchers at University of California, Davis finds that California regulators may be drastically underestimating chemical-intensive agriculture’s contribution to nitrogen oxide (NOx) caused air pollution, acid rain, and respiratory illness in the state. While NOx pollution is usually associated with energy production and vehicle emissions, fertilizer use on crop fields is contributing to significant air pollution problems. Advocates say that the study is an urgent call for farmers to eliminate dependency on soluble, synthetic, nitrogen-based fertilizers and adopt the use of insoluble soil amendments that support soil biology that provide plants with nutrients. See Daily News on this.
Beyond Pesticides has long warned consumers about the volatility of pesticides used in and outside the home. Many insect baiting stations are labeled “nonvolatile” but may still off-gas noxious poisons into one’s home. The propensity for herbicides such as dicamba to volatilize after use has led to a rash of nontarget drift and damage to neighboring crop fields. The present study adds another layer of concern to these already toxic products, and indicates that the U.S. Environmental Protection Agency must more seriously consider secondary effects like volatilization-caused air pollution when considering whether to continue allowed uses of a pesticide.
All unattributed positions and opinions in this piece are those of Beyond Pesticides.
Source: Nature, Washington Post, Science
