Air pollution is often associated with huge plumes of fumes spewed by grey power plants or refineries. But we shouldn't ignore the contribution household activities have on air pollution, researchers warn. Cooking and cleaning, for instance, generate significant amounts of volatile chemicals and particulate matter inside homes, which eventually escape into the atmosphere. According to researchers at the University of Colorado at Boulder, indoor air quality levels can be on par with that of a polluted major city during household activities.
"Homes have never been considered an important source of outdoor air pollution and the moment is right to start exploring that," said Marina Vance, an assistant professor of mechanical engineering at CU Boulder. We wanted to know: How do basic activities like cooking and cleaning change the chemistry of a house?
Vance and colleagues built a 1,200-square-foot home from a scratch on the University of Texas Austin campus, which they equipped with sensors and cameras. Over the course of a month, the researchers monitored air quality inside the manufactured home as they performed all sorts of household activities, including preparing a Thanksgiving dinner in the middle of summer.
Although the experiment, called HOMEChem, is not completed yet, the preliminary results suggest that homes can be a significant source of indoor pollution, such as volatile organic compounds (VOCs). Even basic tasks like boiling water over a stovetop flame can contribute to high levels of air pollutants and suspended particles, negatively affecting our health. In fact, the indoor concentrations measured by the researchers were so high that sensors had to be recalibrated almost immediately after the experiment started.
"Even the simple act of making toast raised particle levels far higher than expected," Vance said. "We had to go adjust many of the instruments."
The public and policymakers are well aware that emissions from transportation can damage our health and the environment. This awareness has been translated into public measures that have led to considerable reductions in emissions. Meanwhile, levels of household chemical pollutants have gone up.
The full effects of household activities on air pollution are not yet understood, so it's much too early to make recommendations on policy or consumer behavior. However, the authors believe there is enough evidence to warrant more research. In the future, perhaps we should be as diligent about how much pollution appliances and cleaning products generate as we are now with our vehicle emissions.
"There was originally skepticism about whether or not these products actually contributed to air pollution in a meaningful way, but no longer," said Joost de Gouw, a CIRES Visiting Professor. "Moving forward, we need to re-focus research efforts on these sources and give them the same attention we have given to fossil fuels. The picture that we have in our heads about the atmosphere should now include a house."
If you're looking for a quick and eco-friendly fix to some of your home's indoor pollution, look no further than potted plants. A study performed by the National Research Council of Italy found that indoor plants absorb carbon dioxide and release oxygen through photosynthesis, absorb pollutants and store them in the soil-root system, and also increase humidity in the room by transpiring water vapor through their pores. Check out our list of 7 potted plants that are especially efficient at removing volatile chemicals from inside your home.
The results were published in the journal Science and presented at the 2019 AAAS Annual Meeting in Washington, D.C, happening this week.