You’ve read about the dangers of outdoor pollution, seen pictures of heavy smog over New Delhi and acid rain in Los Angeles. These threats to our health have been well-researched and, in many cases, mitigation is underway. But, did you know that the worst pollutants may not be in the skies of New Delhi or Los Angeles…. but right here, lurking inside your own home? What’s even more concerning is that scientists have just now begun to study them.
What is Homechem?
A modest twelve-hundred-square-foot prefabricated house sits on the grounds of the University of Texas at Austin. From the outside, it may seem like an ordinary home, unworthy of attention, but indoors, extraordinary things are happening… most of them in the kitchen.
Homechem (House Observations of Microbial and Environmental Chemistry) is an initiative to develop new instruments and databases for the study of indoor atmospheric chemistry run by twenty research groups from thirteen universities. The house at UT, known as UTest House is where the study is based. Last year 60 scientists spent 4 weeks at the home cooking, cleaning, and measuring emissions to determine what exactly is in the air we’re breathing indoors.
Delphine Farmer, a chemist based at Colorado State University, is one of the scientists leading the study. She was dismayed by how little research had previously been done on indoor air.
“I realized that we know nothing about indoors from a chemistry perspective,” she said. “It was very clear that it was an area that was ripe for study, and that the indoor community just hadn’t had the resources we have in outdoor atmospheric chemistry.”
Outdoor atmospheric chemistry has received a lot of attention…and for good reason. Globally, outdoor air pollution kills around 4.2 million people a year. But, humans only spend about 10% of our time indoors. What if those same chemicals that are killing people outside are present in even higher concentrations inside?
What happened in UTest House?
Each day of the month-long study, scientists gathered in UTest House to cook, clean, and eat together. The culminating event of the study was the preparation of two Thanksgiving dinners.
While the scientists went about daily activities, they used high-level equipment to measure how their behavior changed the air quality. What they found was that the instruments, which were designed to measure outdoor pollutants, had to be recalibrated to measure the significantly higher concentrations that build up indoors.
What did they discover?
Scientists were alarmed at how much their activities affected the air quality. Something as simple as toasting bread resulted in a huge increase in the presence of VOCs, or volatile organic compounds. While some VOCs such as benzene and toluene, are already known to be harmful when inhaled, there is a lot scientists still don’t understand about how VOCs impact health.
It wasn’t just the toaster that impacted air quality. Stovetop cooking, baking, and even peeling fruit all put pollutants into the air. In fact, as the scientists prepped for their Thanksgiving dinner, they noticed something alarming…. fine particulate matter rose to a range that the Environmental Protection Agency’s Air Quality Index defines as “very unhealthy.”
Of all the dangerous pollutants in the air, the most hazardous to your health are fine particulate matter, also known as PM 2.5, and ultrafine particles. PM2.5 are composed of a mixture of solid and liquid particles that are suspended in the air. They’re easily inhaled and are able to penetrate deep into your respiratory system.
Long term exposure to PM2.5 can cause permanent respiratory problems such as asthma, chronic bronchitis, and heart disease. PM2.5 particles also elevate the likelihood of premature birth and infant mortality.
One recent study called PM 2.5 “the largest environmental risk factor worldwide,” responsible for many more deaths than alcohol use, physical inactivity or high sodium intake. Another study showed that air pollution in the form of PM2.5 reduces global life expectancy by more than a year.
Because of the dangers of PM2.5, when outdoor air reaches these levels, an alert is signaled to warn people (even those without underlying conditions) of the serious risk of heart and lung damage.
In the US, these alerts have become rare. After the passage of the Clean Air Act in 1963, and the creation of the Environmental Protection Agency, in 1970, strict regulations have been put on outdoor air, with heavy penalties for rule-breakers. But, unlike outdoor air, the air inside our homes is largely unregulated and mostly ignored by researchers… until now.
What are the long term implications?
We are still at the beginning of understanding indoor air. Homechem was the world’s first large-scale collaborative investigation into the chemistry of indoor air. Dissecting and understanding the data from the study will take years, and unfortunately, even when they discover what is in indoor air, they still won’t know how it affects human health. Years of research and additional studies will be needed to understand the medical impact. But, preliminary data from Homechem makes it clear that indoor air is a lot more complicated and possibly lethal than we ever would have imagined.
How can we protect ourselves?
There are no alarms that go off in our home when dangerous levels of pollutants are present, and yet, it seems likely that every day we surpass the EPA’s limits for air quality indoors. What that means for our health is not yet known. But, until more research is done, the best thing we can do is to protect ourselves. Fortunately, there are a number of things we can do to lower indoor pollutants.
Buy an electric stove. The best way to keep pollutants down in your kitchen is to opt for an electric stove. But, if you already have a gas stove, there are some things you can do to make it safer to use.
Make sure that your stove has been properly installed with a hood or fan that leads outside. Because stoves are the only major indoor gas appliance not required to be vented outdoors, it’s important to be specific when having your stove installed or adjusted.
Use your fan when you cook. While fans may be noisy or bothersome to remember, they can be helpful in reducing pollutants, as long as they are vented outside.
Open windows. Because few stoves are properly installed with adequate ventilation, it may be best to open a window while you’re cooking, especially if the air gets smoky or has strong smells.
Reduce the use of harsh cleaners and scented products. While VOCs are almost impossible to eliminate in your home, you can reduce them by using natural cleaning products and avoiding anything scented.