Car Seat Foam Could Emit Cancer-Causing Chemicals, Study Says

Operating a motor vehicle certainly comes with a level of risk, but simply breathing while driving usually isn't among them. That may not be the case, according to a recent study published by the American Chemical Society. It points to a specific flame-retardant chemical used on vehicle seats discovered in the air of car cabins. And it could increase your risk of cancer if you breathe it in.

The chemical in question is tris (1-chloro-isopropyl) phosphate, known simply as TCIPP. It's a flame-retardant additive commonly used in polyurethane foam, which is commonly used for seats in pretty much every car on the road today. The study included 155 participants driving vehicles from 2015 or newer. To determine potential changes relating to temperatures, 101 tests were conducted in winter and 54 took place in the summer.

The results were fairly straightforward. A full 99 percent of vehicles showed traces of TCIPP in the air, matching samples of seat foam in which the additive was present. In warm temperatures, the concentration of airborne TCIPP was between two and five times higher. In short, the heat promotes outgassing from the seats, putting more of the chemical in the air.

Exactly how much TCIPP are we talking about? The study found 0.2 to 11,600 nanograms per gram. One nanogram is a billionth of a gram, so it's an exceedingly small quantity. But, a 2023 toxicology report found possible carcinogenic connections between TCIPP and rats. So even a small exposure could be problematic.

That's partly what the study seeks to determine. The effects of flame retardant chemicals have been evaluated in various situations, but researchers say the automotive realm is an "understudied source." AAA says the average American driver spends an hour every day in a car, and the concentrated environment can be made worse by warmer temperatures. The study recommends opening windows if parked outside to both reduce interior temperatures and promote better airflow. Using air conditioning and avoiding the interior recirculation setting may also help.

Ultimately, the study concludes by saying more evaluation is needed to fully understand the scope of potential danger regarding TCIPP in