VOCs and Indoor Air: The Chemicals You Breathe at Home

VOCs, or volatile organic compounds, are chemicals that turn into gas at room temperature. They come off paint, cleaners, air fresheners, glues, new furniture and gas stoves, and they build up indoors. The EPA says levels of many VOCs are consistently higher inside homes than outside, up to 10 times higher. Most cause short-term irritation, but a few, including benzene and formaldehyde, cause cancer.

Some activities cause big spikes. The EPA says that during and for several hours after jobs like paint stripping, levels can reach 1,000 times outdoor background levels.

In the short term, VOCs can cause eye, nose and throat irritation, headaches, nausea and loss of coordination. Some can damage the liver, kidneys and nervous system, and some cause cancer.

Two VOCs stand out.

Long-term exposure to high levels can cause leukemia. Indoors, benzene comes from tobacco smoke, stored fuels, paint supplies and attached garages. A Stanford study found that gas stoves can raise indoor benzene above levels found in secondhand smoke. In 2022, after Unilever and Procter & Gamble recalled dry shampoos, the testing lab Valisure found benzene in 70 percent of the dry shampoo batches it tested, some far above the FDA's limit. Aerosol propellants were reported as the source in the recalled products.

Formaldehyde is classified as a known human carcinogen, and scientists have tied it to nose and throat cancers and leukemia. It comes off pressed-wood products, some fabrics, glues and some hair-smoothing treatments, and from gas stoves. Levels are usually highest in new homes and around new furniture.

VOCs weren't among the seven chemical groups the MAHA Commission's 2025 report named, though its September strategy calls for evaluating how air quality affects children. The flashpoint for the movement has been formaldehyde.

In December 2024, the EPA concluded that formaldehyde poses an unreasonable risk to health. A year later, the Trump EPA proposed revising that analysis to assume a safe threshold below which formaldehyde doesn't raise cancer risk, a break from how the agency has long treated cancer-causing chemicals that damage DNA. Scientists and a group of state attorneys general, including California's, opposed the change. In April 2026, MAHA activists pointed to it as one of several EPA decisions they say contradict the movement's goals.

The EPA says it still considers formaldehyde an unreasonable risk and is writing a rule to manage it.

There are no federal limits on VOCs in the air inside homes. Instead, rules target specific products. Federal law limits formaldehyde emissions from composite wood such as plywood and particleboard, and the FDA uses a 2 parts-per-million benzene limit when deciding whether products are contaminated.

The biggest pending federal decision is the formaldehyde rule. Public comment on the EPA's revised analysis closed in February 2026, and states have been passing their own limits on formaldehyde in products.

Open windows when cleaning, painting or cooking, and run a range hood that vents outdoors whenever you use a gas stove.

Skip plug-ins and heavily scented candles too. Open a window instead, and pick pump sprays over aerosols.

Paint when you can keep the windows open, and air out new furniture, mattresses and flooring before they go in bedrooms.

More ways to cut exposure:

Yes. The EPA says levels of many VOCs are consistently higher inside homes than outside, up to 10 times higher, and can reach 1,000 times outdoor background levels during and after jobs like paint stripping.

A Stanford study found that gas stoves can raise indoor benzene above levels found in secondhand smoke. Run a range hood that vents outdoors whenever you cook with gas.

Formaldehyde is classified as a known human carcinogen, and it comes off pressed-wood products and glues. Levels are usually highest around new furniture, so air new pieces out and look for "TSCA Title VI" or "CARB Phase 2" compliance on the label.

Healthy, Again. is health news, not medical advice. Talk to your doctor about any health concern.