Your car is exposing you to dangerous chemicals

By Naveed Saleh, MD, MS | Fact-checked by Barbara Bekiesz
Published May 23, 2024

Key Takeaways

  • You might want to rethink your summer road trip: Foam used throughout the interior of cars and other vehicles represents an understudied health risk for drivers and passengers.

  • Flame retardants in vehicles, while legally required, increase reproductive harm and the risk of cancer; these risks increase with time spent inside the car—and as temperatures warm.

  • Furniture surfaces, dashboards, and other such areas should be cleaned regularly to decrease health risks—especially if you have children.

More than 75% of Americans are planning a road trip this summer. Nearly 87 million people will travel more than 250 miles from home, and 15 million people will travel more than 1,000 miles from home.[] This translates to a lot of time spent in cars. 

Flame-retardant chemicals are added to various consumer products, including electronics, furnishings, and cushions in cars.[]

For summer road trippers, the presence of flame-retardant chemicals poses a health risk, which is exacerbated by increasing summer temperatures and more time spent behind the wheel. 

Even when they’re not taking a long road trip, the vast majority of Americans spend a lot of time in their car: 91% travel to work in a personal vehicle, with the average driver spending 55 minutes a day in vehicles. They also transport their children in cars, making the environment dangerous for an especially vulnerable population.

Flame retardants

Researchers writing in Environmental Science & Technology explain that most of the flame-retardant chemicals are added—and not chemically bound—to the foam seating in cars and other goods to meet flammability standards.[] They are present in both a gas and a condensed phase (ie, adherent to car surfaces) depending on the ambient environment.

The release of flame retardants into the environment in dust results from vapor pressure and thermodynamic partitioning. Greater release occurs in warmer temperatures, affecting drivers and passengers in the summer, in particular.

In one recent study, researchers found that, among 51 foam samples from separate vehicles, organophosphate esters were the most commonly collected class of flame retardant.[] The detection frequency for tris(1-chloro-isopropyl) phosphate (TCIPP) was 99%. The concentrations of TCIPP in foam varied by the season and temperature, ranging from 4-times higher in winter vs 9-times higher in summer.

Potential health risks

Organophosphate esters are linked to reproductive harm, adverse birth outcomes, and carcinogenicity. Animal studies indicate that early life exposure is of particular detriment to the developing brain and reproductive system.[]

In rats, exposure to tris(1,3-dichloro-2-propyl) phosphate (TDCPP), another ubiquitous flame retardant, correlated with increased numbers of benign, malignant, and combined malignant and benign liver tumors. Rates of benign kidney tumors were also increased in both species, and male rats experienced a higher rate of testes tumors.

Another organophosphate ester, tris(1,3-dichloro-2-propyl) phosphate (TDCIPP), has been linked to lowered, disturbed thyroid hormone function and cancer; it was added to the California EPA Prop 65 list in 2011.[]

Based on the research, the Harvard TH Chan School of Public Health cites the following as risks from exposure to flame retardants in people who are pregnant:[]

  • 10% lower chance of fertilization leading to pregnancy

  • 31% decreased chance of the embryo implanting in the uterus

  • 38% fewer live births

At the same time, exposure to polybrominated diphenyl esters (PBDEs) increased the risk of thyroid disease, by two-fold in post-menopausal vs younger women.

“Common flame retardant chemicals can have dramatic effects on health, especially for pregnant or post-menopausal women,” authors of the Harvard report stated. “Couples undergoing IVF, or otherwise trying to conceive, may want to limit exposure by buying products that are flame-retardant free.” 

What can be done

Flame retardants are not necessary to prevent fire risk. The Environmental Protection Agency (EPA) recognizes that due to higher exposure levels, children are at particular risk from flame retardants.[]

They recommend the following steps to decrease exposure:

  • Wash your hands after being inside a vehicle

  • Dust vehicle surfaces frequently using a damp cloth

  • Mend tears in upholstery

  • Prevent young children from chewing on products that contain flame retardants

  • Regularly wipe and vacuum vehicle interiors, such as seats and dashboards

  • Purchase products that are free of flame retardants

Fortunately, the EPA is actively exploring regulatory options for these agents. 

What this means for you

Foam found in furniture and car seats poses health risks due to the presence of flame retardants. These agents are linked to reproductive harm, including adverse birth outcomes, as well as different types of cancer. Risks are highest in children due to higher levels of exposure. Physicians should advise their patients to clean furniture and car surfaces regularly and mend any tears in upholstery to help reduce their risk.

Read Next: Your cicada survival guide
Share with emailShare to FacebookShare to LinkedInShare to Twitter