Does polyurethane foam in couches and mattresses release formaldehyde and other toxic gases?

What's actually in it

Polyurethane foam is everywhere in your home. It's the cushioning in your couch, the padding in your mattress, the stuffing in throw pillows, and the core of many children's play mats. Over time, the foam doesn't just compress and wear out. It undergoes a slow chemical reaction with oxygen called autoxidation.

This reaction breaks down the foam's polymer structure and releases volatile organic compounds (VOCs) into the air. You breathe these gases in every time you sit on the couch or sleep on the mattress. The "new furniture smell" is these chemicals off-gassing at their peak, but the process continues for years.

What the research says

A 2026 study in Polymers analyzed the specific VOCs released by polyurethane soft foam as it oxidizes. The researchers identified three particularly concerning chemicals: formaldehyde, acetaldehyde, and acrolein.

Formaldehyde is classified as a known human carcinogen. It irritates the eyes, nose, and throat, and long-term exposure increases the risk of nasopharyngeal cancer and leukemia. Acetaldehyde is a probable carcinogen. Acrolein is a potent respiratory irritant that damages lung tissue.

The study measured the rate at which these chemicals form over time. The release didn't stop after the initial off-gassing period. The foam continued to break down and emit VOCs for the entire duration of the study. Higher temperatures sped up the reaction, which means foam in sun-facing rooms or near heaters releases more chemicals.

The amounts released from a single cushion may be small. But think about how much foam is in a typical home: a couch, a mattress, bed pillows, armchairs. The cumulative emissions from all that foam add up, especially in poorly ventilated rooms.

When buying new furniture, air it out in a well-ventilated room or garage for several days before regular use. Look for mattresses and couches with CertiPUR-US or GREENGUARD Gold certification, which cap VOC emissions. Natural latex, wool, and organic cotton are lower-emission alternatives.