aIR pollution is easy to ignore on a day-to-day basis, but in recent decades researchers have amassed a compelling list of evidence that it can pose a major threat to human health, from mental health and child development to heart disease. Recent events, such as the East Palestine, Ohio, train disaster that released toxic chemicals into the air in early February, have put such risks in the spotlight, causing many in America to reconsider the safety of the air they breathe.
While home is where many people feel safest, that may not be entirely true when it comes to air pollution. The walls that keep the world out can also contain dangerous toxins. There are some things you can do as an individual to protect your family from the effects of air pollution at home.
When should I consider air quality tests in my home?
In most cases, some experts recommend testing air quality if you’re concerned about specific pollutants, rather than assessing overall air quality. According to Geoffrey Siegel, a professor of civil engineering at the University of Toronto who studies indoor air, more general home tests usually don’t justify the cost because the air is constantly changing and the tests can easily become contaminated. “The reason we measure indoor air is often because of a problem we know is there, rather than finding some new problem,” he says.
If you know there’s a chance your home has been exposed to a potential source of pollution, such as the East Palestine train disaster, that’s an obvious, if fairly rare, situation where more extensive air quality testing makes a lot of sense. More typically, you’ll want to test after you’ve found the source of the contamination—for example, if you’ve had asbestos remediation done in your home, you might want to test to make sure it’s been removed, says Stuart Butterman. Professor of Environmental Health Sciences at the University of Michigan. In those cases, Butterman recommends testing for specific toxins. If your home feels “stuffy or damp,” Batterman also suggests testing CO2 levels and humidity to make sure your home is properly ventilated.
Another toxin to be aware of is radon. According to the US Centers for Disease Control and Prevention, the odorless gas is the primary environmental cause of any cancer and is responsible for 21,000 lung cancer deaths in the US annually, according to the Environmental Protection Agency. Radon occurs naturally in rocks and soil and can leak into a home from anywhere it comes into contact with the ground, especially through foundation cracks, French drains, or sump pumps. The EPA recommends testing for radon if someone is going to spend a significant amount of time in the lower level of the home (for example, if the basement will be used as a bedroom), or if you are buying a new home. Because radon levels vary geographically, Siegel also recommends checking a map provided by your state or local health department to see if you live with high radon levels.
Another concern is carbon monoxide, an odorless, flammable and toxic gas that can leak from various places in your home, including gas furnaces, heaters, and cars (if they’re in an attached garage, say). The CDC recommends having Have your heating systems and gas appliances serviced annually and battery-operated carbon monoxide detectors installed.
How much do air quality tests cost?
The cost of air quality tests can vary based on many factors, including the number of toxins you’re testing for, how common the test is, and the sensitivity of the test. Some tests, such as a radon home test, can cost $10 to $30, according to HomeAdvisor. Depending on where you live, state and local health departments may even provide free radon tests. A professional radon inspection, however, can cost up to $800, says Home Advisor. Air quality testing for asbestos, meanwhile, can cost about $287 to $585, while professional testing for volatile organic compounds such as formaldehyde can cost $200 to $300 per sample.
The public can also get free air quality testing after a disaster. Since the disaster in East Palestine, the EPA told TIME it has helped with air quality testing in 600 homes paid for by Norfolk Southern, the railroad company that operated the train.
Why is air quality testing so expensive?
Air testing, especially for less common chemicals, requires three expensive things: specialized equipment, expertise, and time.
Advanced air quality testing requires hiring an expert, and collecting samples, testing them and analyzing the data is a lot of work, said John Durant, a professor of civil and environmental engineering at Tufts University. Additionally, after an incident like the disaster in East Palestine, testing must be conducted multiple times for the same group of chemicals. Ideally, Durant says, samples should be collected in different parts of the house, in different weather conditions, and during different seasons. In the spring, for example, chemicals can be released as the soil becomes softer.
What should I do if I detect air toxins in my home?
Once you’ve identified an airborne poison in your home, the next step will likely depend on whether the contaminant is coming from outside or from some internal source. In the event of a disaster where contaminants may be outside, Siegel recommends sealing off your home with plastic sheeting and tape, especially on lower floors and in the winter. At least keep your doors and windows closed as much as you can. For radon contamination, the EPA recommends sealing foundation cracks and installing vents and vents.
For more high-tech solutions, Siegel suggests using heating and air conditioning systems to create “positive pressure”; this means placing such systems in a position that filters the air as it enters and creates a greater pressure inside than outside. If such a system isn’t already installed, adding this option may be easier in more modern homes, which tend to be more airtight, Siegel says; the first step is to ask the contractor if it is possible.
A portable, connected air filtration system can also help remove particulate matter (dust or soot that comes from wildfires, motor vehicles, and construction tools) from your air “continuously and quietly.” Some systems can be purchased or modified with filters that can absorb more pollutants from the air. For example, activated carbon can absorb gases.
What about internal pollution sources? Cooking on a gas stove, spritzing on beauty products, or buying a new sofa may seem harmless, but it can add toxins to the air in your home. If you’re concerned about the air quality in your home, Butterman suggests three steps: eliminate or control it, use ventilation and filters if necessary.”
One of the main pollutants is combustion, the process of burning something. For example, cooking on a gas stove can release a variety of toxins, including nitrous oxide, methane and carbon dioxide, so Durant recommends using a fan during and after cooking. Otherwise, avoid burning things inside your home, especially if someone has breathing problems such as asthma or COPD. This includes lighting candles or incense. Just because something smells good doesn’t mean it’s safe, and foul odors aren’t necessarily dangerous, Siegel says. “Smell is not a good indicator of anything,” he says. (Notably, however, gas companies add mercaptan to natural gas so you can smell it. If you smell gas, you should get out of your home and call your gas company or 911.)
Everyone should consider installing portable air filtration systems around their home and replacing filters regularly, Siegel says. They can be especially useful for removing particles, he says, that are not safe at any level. “The lower the concentration, the safer we are,” Siegel says.
The CDC offers a wide range of resources on how to protect your family, including information on lead, asbestos and other toxins. And if you’re concerned that you or a loved one is in immediate danger, the National Poison Hotline (1-800-222-1222) can be a helpful resource in the United States.
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