You have doubtless heard the expression “Your home is your castle.” For many, though, it is the car that is a kind of castle. That because people spend a lot of time in their cars. Many have to commute to and from work. Others spend hours shuttling kids to and from activities. And then there is shopping! Oh, let’s not forget vacations. That can represent many hours cooped up in a car. New research (Environmental Science & Technology, May 7, 2024) suggests that your car seat may pose a greater risk than anyone could have imagined.
What’s the Problem with Your Car Seat?
Do you remember the controversy surrounding flame retardant chemicals in mattresses and foam cushions found in couches and chairs? It was a very big deal a few years ago. We interviewed some of the country’s leading toxicologists about this problem over the last decade. If you would like to refresh your memory, here are two radio shows/podcasts:
Here is an article that addresses one specific common health concern:
Because consumers became concerned about the health hazards of flame retardant chemicals, most mattresses, foam cushions and other home furnishings no longer contain these chemicals. But most cars do. That’s because the National Highway and Transportation Safety Administration (NHTSA) enforces the Federal Motor Vehicle Safety Standard 302 that has required flame retardant chemicals in cars since the 1970s.
What Are the Health Concerns Associated with Flame Retardants?
Let’s start with the big one: cancer. One of the chemicals found inside cars is TCIPP tris(1-chloro-isopropyl) phosphate. It is known as an OPE (organophosphate ester). Concerns have been raised that this and related chemicals may be carcinogenic. In addition, there is concern that these OPEs could be toxic to the thyroid and the brain.
The authors of the new research conclude:
“The results of this study suggest that personal vehicles are an important microenvironment to consider for understanding human exposure to FRs [flame retardants]. In particular, the results showed the extensive use of organophosphate esters (OPEs) by the vehicle industry today. TCIPP was detectable in 99% of vehicles, and vehicle foam was identified as a source of this compound. To the authors’ knowledge, this is the first study to explore the potential associations between FR applications in car seat foam and indoor air levels. The frequent detection of TCIPP in vehicles is particularly concerning given that a 2023 United States National Toxicology Report found evidence of carcinogenic activity in male and female rats and mice exposed to TCIPP, with observed increases in liver adenomas, liver carcinomas, and uterine adenomas or adenocarcinomas. Carcinogenic potential of other OPEs has led to restrictions on their use, such as TDCIPP, which was added to the California Proposition 65 (Prop 65) List in 2011 and has been banned from certain products such as children’s pajamas and mattresses.”
Air Pollution Inside Cars:
Most of us have had the experience of driving through air pollution. It might have been a truck in front of us belching foul-smelling exhaust fumes. Or perhaps you have driven through an area where factories were polluting the air with nasty odors. And if you have driven in the country you might have encountered the smell of skunk. You probably rolled up your windows and tried to escape as quickly as possible.
Chances are you never imagined that your car’s indoor air quality could be contaminated with chemicals you can’t see or smell. Scan back to the quote above. TCIPPP has a 99% detection frequency. In other words, it was discovered in virtually all the vehicles tested.
These were not old jalopies. The 101 vehicles sampled mostly ranged from 2015 to 2022. There were hybrids, electric and gas-powered cars in the study.
The investigators discovered:
“A total of 17 different FRs [flame retardants] were identified in at least one silicone sampler, suggesting that a wide range of FRs are present in vehicle cabin air…Most detections were organophosphate esters (OPEs), with 12 OPE compounds detected in at least one sampler.”
One fascinating discovery was that summer air samples differed significantly from winter air samples. Just think about how hot your car can get if you leave it in a parking lot for an hour or two.
The researchers reported:
“Summer concentrations of TEP, TIBP, TNBP, and TCIPP were significantly higher than winter concentrations…Among these paired samples, the median TCIPP concentration was 56 ng/g in the winter, which increased ∼4-fold to 231 ng/g in the summer. Similar increases from winter to summer were observed for TEP, TIBP, and TNBP, with median summer concentrations being 1.6, 4.9, and 5.3 fold higher, respectively.”
One might reasonably conclude that car seat foam breaks down and liberates flame retardant chemicals faster when temperatures climb.
Do We Need Flame Retardant Chemicals in Car Seat Foam?
Here is the paradox. These chemicals, required by Federal Motor Vehicle Safety Standard 302 may be causing more harm than go0d. Patrick Morrison is director of health, safety, and medicine for the International Association of Fire Fighters.
He is quoted in the in the Free Press Journal (May 9, 2024):
“Firefighters are concerned that flame retardants contribute to their very high cancer rates. Filling products with these harmful chemicals does little to prevent fires for most uses and instead makes the blazes smokier and more toxic for victims, and especially for first responders.“‘I urge NHTSA (US National Highway Traffic Safety Administration) to update their flammability standard to be met without flame retardant chemicals inside vehicles,’ he added.”
But Wait…There’s More: Stain Resistant Chemicals in Your Car Seat?
Perhaps you have heard about PFAS (per- and polyfluoroalkyl substances) in water. These “forever” chemicals have been used in non-stick cookware for years. They are also employed in food packaging, carpets and clothes. What makes them so popular is their ability to resist water and stains. That is why they can be found in water-resistant boots and rain gear.
PFAS compounds can also be found in automobiles. People love to snack in their cars. They drop food and spill beverages on car seats. Not surprisingly, car manufacturers may sometimes include PFAS chemicals in their car seat fabrics to prevent stains. It seems sensible…until you realize that these compounds can also break down and potentially contaminate the air inside your car.
What Can You Do To Reduce Exposure?
- Get Flame Retardants OUT of Cars! The most important thing we can all do is to encourage the NHTSA (National Highway Traffic Safety Administration) to get rid of flame retardants in our car seats and any place else they might show up in our vehicles. The feds should also get PFAS chemicals out of cars and other products.;
- Bring Outside Air into Your car. Most modern vehicles have an option to recirculate air or bring in outside air. Opt for fresh air whenever possible. It may not be as energy efficient, but you can reduce the amount of pollution inside your car by bringing in fresh air.
- Open Your Windows. If your car has been sitting in the hot sun and is sweltering inside, open the windows and let in some fresh air for a few minutes before turning on the AC.
- Improve Your Air Filter Efficiency. Your car should have an air filter. Most people rarely think twice about changing it. Ask your dealer or garage if your model vehicle can accept a high-efficiency particulate air (HEPA) filter.
- Use a Sunshade on the Dashboard and Park in the Shade! Try not to let your car bake in the sun. The higher the inside temperature, the greater the likelihood you will have particles of unwanted chemical compounds floating around the inside of your car.
The Law of Unintended Consequences:
We are always impressed by the law of unintended consequences. Regulators at the NHTSA thought they were doing something good when they required car manufacturers to put flame retardants in car seat cushions. Now that they have been informed that this might have been a very bad idea, they should immediately take action and get those chemicals out.
While they are at it, they should also encourage car makers to get rid of PFAS chemicals in cars. Cutting back on plastic might also be a good idea.
What do you think? Please share your thoughts about car-interior air quality in the comment section below.
