This post will go through the techniques used to help promote offgassing of the volatile organic compounds (VOCs) in a new car.
That “new car smell” is made up of VOCs and we can speed up their release or mitigate them with a number of hacks.
Not all toxins in new vehicles are gasses (VOCs) however. We will also look at avoiding, cleaning, and sealing nonvolatile toxins like metals and flame retardants.
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1. Pick a Less Toxic Car
Makes and Models
The most recent study that compares the toxicity of vehicles across brands was in 2012. The study revealed the top picks to be the Honda Civic, Toyota Prius, and Honda CR-Z.
The worst of the bunch were Mitsubishi Outlander Sport, Chrysler 200, and Kia Soul. Though things could have changed with these brands since 2012.
Toxins of Concern in Cars
The most worrisome toxins are metals, flame retardants, and PVC followed by VOCs.
A number of cars are now free of PVC and some have cut out brominated flame retardants (though replaced with flame retardants that are just as worrisome).
Some models contain more metals than others. Metals and flame retardants are not VOCs and they have no odor. They also do not dissipate the way VOCs do. Flame retardants will continue to come out of the foam for the lifetime of the foam. Metals also are rubbed off or released over time.
Honda is still popular in 2021 amongst those sensitive to chemicals. The company puts out an environmental report every year which shows that most Honda and Acura models are PVC-free and they use low-VOC adhesives, tapes, foams, and coating materials inside the vehicles (source).
Ford has also made a big effort recently to reduce offgassing (source 1, 2).
Volvo eliminated chrome from their leather (source).
See Them in Person
If you are sensitive to offgassing you will likely want to look at a few different makes and models in person to see how you feel in them.
A 2007 study showed that interior VOC emissions varied greatly between makes models and trims and even within the same make/model/trim. (Source)
You may also want to consider a car that has been on the lot for longer and may have partially offgassed already.
Certifications for Less Toxic Cars
There isn’t a universal or widespread certification for indoor toxicity of vehicles.
TUV Toxproof certifies levels of interior vehicle toxins including heavy metals. They have not released publically what levels they are allowing. And without being able to compare that to vehicles that have not applied for this certification, it makes it hard to make much use of it. Brands that are certified include Mercedes, Volvo, Renault, Land Rover, and Jaguar.
I think this is a good idea and I look forward to having a certification like this become more transparent and more widespread.
Some fabrics in interior cars are certified by Oko-Tex Standard 100. Volvo has this certification. However, the fabric is not my biggest concern in the vehicle.
How Long Does a New Car Take to Offgas?
In terms of the chemicals that are volatile and produce that new car offgassing odor, this study found a lot of variability between brands. However, after one year the VOCs were down to 1/10th the original level.
The offgassing of VOCs is not a linear process, it’s on an exponential curve. There is a sevenfold decrease in the first month of use, or about 20% per week (source). To facilitate offgassing there needs to be air movement (and heat helps a lot too).
2. Heat it and Air it Out
Heat and Air While Parked
Heat, air, and time are certainly the main ways to offgas a vehicle. You can heat it by putting it in the sun, by running the heating system, or even with space heaters (very carefully in a small space).
When you are heating materials you are releasing the VOCs and also creating new VOCs (this study explains), so make sure when you are heating up the new vehicle you are airing it out substantially at the same time so that the gasses have somewhere to go.
Windows should be open while you are heating the vehicle. Windows can also be left open anytime it’s safe to do so.
When it’s raining or otherwise unsafe to leave the windows down, I would reduce the temperature by using window sunscreens because the VOCs being released have nowhere to go.
Aim for a substantial amount of airing out with heat in the first six months.
Temperature Control and Air While Driving
When you are driving you will want to keep the HVAC on fresh air intake which reduces VOCs by diluting the air, or open the windows.
While you are driving, lower the temperature to reduce the release of VOCs inside the vehicle.
3. Deep Clean your Vehicle
Deep Clean the Seats
If you have cloth seats I would have the seats cleaned with a shampoo extraction, or possibly steam cleaned.
AFM Safecoat makes a carpet shampoo that can be used for this purpose in lieu of the more toxic products that car detailers use.
You want to use an extractor that pulls some of the chemical coatings off the fabric as well as toxins that got absorbed by the fabric when the car was brand new. You can use that on carpet floors as well.
Make sure the upholstery can dry out quickly and thoroughly to prevent mold growth. My post on preventing mold in cars goes into more detail.
To capture flame retardants (FR) you want to use a HEPA vacuum (add the HEPA filter and bags) as often as is reasonable for you. FR are constantly coming out of the foam for the lifetime of the product. They are not gasses.
Wipe Down Surfaces
Phthalates and metals are other chemicals that live in dust. Wiping down all hard surfaces alongside vacuuming is a good way to mop up these chemicals.
While other websites recommend microfibers clothes because they are particularly good at grabbing on to dust where many of these chemicals live, I would also be concerned with bringing those back into the house carrying heavy metals, phthalates, and flame retardants, and I therefore might opt for more disposable clothes, like these ones.
Although it might seem excessive to some, when cleaning up dust that contains heavy metals and flame retardants, I would wear an N95 mask. These toxins are much harder for the body to process and much more fundamental in terms of the cause of illnesses.
You can use a gentle cleaner like AFM Super Clean or any gentle soap that you do well with. Here is my list of cleaning products.
Clean Up Oil Residue
If there is excessive oil residue left on any car parts, you can clean that up with TSP mixed in water. Be careful not to remove lubricants that are needed for the functioning of all the door parts (and other parts of the vehicle).
3. Use Absorption Materials
There are a number of materials that absorb VOCs that can be placed around the vehicle. These are especially useful when the vehicle has to be closed up due to rain, humidity, or for security reasons.
Carbon/Charcoal. My go-to would be carbon/charcoal because it’s relatively cheap and it is effective. These bags from Amazon do help. You can also use activated carbon fabric to cover seats.
Zeolite and Minerals. You can also use zeolite, and the EnvironKlenze odor eliminating pads, which are made of minerals.
Baking Soda or Vinegar. Some articles have suggested putting out bowels or trays of baking soda or vinegar. Those can help. If you have them handy you can put them out for 24 hours and discard them when they are saturated. But they are not as effective as the charcoal.
Absorptive Powder for Seats. You can use the same strategy to absorb VOCs coming out of seats. You can sprinkle baking soda or zeolite powder on the seats, let it sit for 12 hours and then vacuum it up. The challenge with this strategy is that the particles like baking soda particles can get stuck in some fabrics.
Air Purifier with Carbon. While you are storing the vehicle you can also run a full-sized high carbon air purifier. Run it on an extension cord. Here is my list of the best air purifiers for high offgassing. Austin Air is my top pick.
4. Use Sealants to Block Toxins
A less common strategy in a vehicle is to use sealants. In general, you want to offgas anything with heat and air first. As sealing will by definition slow down the offgassing, meaning it actually goes on for longer.
In a car that you cannot heat and air out for any reason, this strategy can be used.
Seal the Fabric Seats. AFM makes a product for sealing in offgassing in carpet which can also be used on car seat fabric. The product AFM Lock Out is spray applied to the seats.
Seal Vinyl. AFM also makes a product called Hard Seal which can be used to seal hard vinyl components. Use three thin coats applied with a sponge. So many new make and models are vinyl free so unless you must go with one that has vinyl, I would look at those other options. I would also be sure of what the material is before going ahead to seal it.
Seal other Plastics. AFM Acrilacq can be used to seal plastic in some vehicles (and is used in Hyundai to seal in some of their plastics). Talk to Green Design Center if you are not sure which product would work best.
The idea to seal surfaces in a car came from the Non Toxic Environments Podcast.
If the plastic components contain heavy metals, which they do according to the Ecology Center report, I would use this sealing strategy.
Use Seat Covers. Plastic seat covers will block flame retardants and metals in the seals.
5. Use Air Purifiers/Filters
There are small air purifiers made for cars but you can also put a full-sized air purifier in the back seat. I will go through both options.
Air Purifiers Made for the Car
Many companies that make air purifiers make a smaller model for vehicles. These plug into the cigarette lighter:
- EL Foust car air purifier has a 60 CFM fan and 3 lbs of carbon. The CFM (the amount of air it’s cycling through it) is good for a car.
- Air Oasis Mobile Unit uses PCO and generates ions. They claim the mobile unit does not give off any ozone. The fan size is not important as this machine puts out ions. The post on PCO explains in more detail.
- IQ Air Atem Car 18 CFM, less than 1 lb of carbon.
- Other popular models are similar, the Aireox Automobile model has 75 CFM fan and 2.5 lbs carbon.
- The Amaircare Roomaid is 32 CFM with half a pound of carbon.
Using a Full-Sized Air Purifier in a Vehicle
I mentioned above that you can use a full-sized air purifier on an extension cord while the vehicle is parked. But you can also use a full-sized air purifier like Austin Air while driving.
These inverters can run an appliance up to 300 watts. Air purifiers are usually around 150 watts. You can put an Austin Air, or another air purifier on this list, on the front seat or backseat. Just make sure it’s secured down really well so it is not a flying missile in a car crash. Use the inverter to run it off the cigarette lighter.
You can buy Austin Air through Amazon and Green Design Center.
The HEPA component can be useful for capturing flame retardants and particulates, but it’s the carbon (or other sorbent materials like potassium permanganate or zeolite) that is going to make the difference in terms of reducing VOCs.
If you are incredibly sensitive, a full-sized air purifier is the way to go.
6. Should You Use Ozone to Offgas a Car?
I would be very cautious before using ozone to reduce the offgassing of a new vehicle.
Ozone works well on specific odors – smoke and fragrance residue most notably. It helps to kill and denature mold. And I did find it useful in offgassing the new glue smell of metal trailers.
But ozone interacts with many VOCs to create some unknowns. Especially in a car where the mix of VOCs can change from vehicle to vehicle new VOCs that we can’t predict can be created.
It also leaves behind oxidation of materials, which smells horrible and can worsen things.
I have heard from folks who have had success using ozone to offgas new cars. If that works for you, carry on. But for folks new to using ozone for VOCs, I would discourage that experiment. See my post on ozone for precautions.
Myths About Offgassing Cars
Masking odors – Other websites are promoting odor masking agents to get rid of that new car smell. Please don’t add more toxic chemicals to cover up toxic chemicals.
Using the car’s cabin filter – This gets mentioned a lot too. The cabin air filter is mainly to protect the HVAC system and keep dust out.
You can add a filter with charcoal or even a HEPA filter. This minimal amount of carbon is not going to make a dent in the offgassing, and would only help when it’s on recirculate.
When you are driving the vehicle during the initial offgassing phase you want to keep outdoor air coming in as much as possible, not on recirculate.
Though it’s still a good way to help keep your HVAC system clean and keep some particulates out if you have high air pollution outside.
For those sensitive to outdoor pollutants, I would use a HEPA cabin filter. This can be especially useful if interior offgassing is forcing you to keep the air on fresh air intake and you are sensitive to outdoor pollution.
Corinne Segura is a Building Biologist with 8 years of experience helping others create healthy homes.
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We are purchasing a 2023 Toyota Corolla and have the option to have the interior ProTech (ceramic coating) applied. Should we get it?
Alex Coleman says
Seriously I hate this smell of the new car it makes me discomfort when I smell it I will try this method lets see if this smell goes away.
we just bought a Volvo XC90 hybrid. At the dealership I had no big issues with the smell of their newly arrived cars. However when I took delivery of my new vehicle it smelt quite strong, in spite of Volvo’s care to use environmentally friendly materials where possible. We are airing it out daily outside, have the carbon bags inside when closed up, and will soon try an air purifier inside. A potentially bigger health problem for me is the amount of EMFs created with all the new tech in the car for which I am feeling some ill effects. I am deactivating as much radio frequency tech as possible to help and will try some shielding fabric on drivers seat/floor as well! Any other ideas for this make and model re. smell and EMFs are appreciated 🙂
I am a potential VolVo XC90 buyer and also has EMF hypersensitivity. I contacted Volvo multiple times about EMF concerns.
To reduce the EMF. Turn of the WIfi and Bluetooth as you did. That is easy. Volvo on call/emergency system is basically a cellular phone. Although it supposed to be active only when pushed, never trust what they say unless you have a device that can measure this EMF signals. I talked with Volvo and it seems that you can get this internal cell phone also turned off/removed by the dealership service center.
Last one but more depressing is the sensors. Most car makers are proud about their blind spot sensors/collusion prevention sensors…. but nobody mentions what it is. These sensors actually use radar/microwave signals similar to 5G, as far as I can tell they operate anywhere between 20GHz to 80GHz. Most EMF detector on market including my device can measure 0.2-8 Ghz. So there is no device available to public to measure how much radiation coming from these sensors. I reached out to volvo about it ad they declined to comment on even what GHz/frequency these radar signals operated.
If you are keeping your cell phone on in the car that is probably producing more EMF that your car.
I spend alot of time on EMFs and still sleep in faraday cage, wifi off at home …etc I can say confidently and strongly to stay away from shielding products unless you can make it 360 degree like a faraday cage. if it is less than faraday cage it may actually may increase EMF exposure in dynamic environments like a car. that is also the reason that cell pone EMF shields may increase EMF exposure rather that protect. They only work in 2 settings, as in faraday cage (360 wrap) and in static environments that EMF is only coming from one direction and is not changing.
There are other types of EMFs like regular electric fields that also may cause problems
I am in between, subaru ascend/Ford forester and Volvo XC90. I am surprised that your volvo had strong smell despite their focus on low VOCs. Subaru had very intense smell but it seems it may be an ventilation issue.
Great article. Thanks for the information.
Leslie Vergara says
Thank you for your wonderful work. <3
I have two questions. Are leatherette seats preferred over cloth? I figured the leatherette at least traps the flame retardants in.
I’m looking for a windshield shade that doesn’t have a prop 65 warning and I haven’t had any luck, they all lost DEHP. Any suggestions?
If the faux leather is polyurethane that is better in my opinion.
Theresa Diaz says
I had a hard time getting in my husband’s car (Mazda CX5.) After about two years of owning it with me not getting in the car, he left it outside for two days with the windows down in the sun and that took care of the problem. I also ran an air purifier inside it but that didn’t help. I had a major problem with five rooms of new carpet in our home. It all had to be torn out and replaced with hard wood. Now we have a new cabinent for a bathroom remodel and I can’t breath near it. I imagine this is alos VOC’s offgasing but this problem is very annoying since I don’t know what the car, the carpet and the wood cabinent have in common so that I can avoid it. I have asthma but walk four miles every day and my asthma is very controlled unless I get around things like this.
The car, cabinets and carpet all offgas VOCs. It’s not just one that we become sensitive to, that’s why it’s called MCS.
Hello. I have a new car that makes me sick every time I get in it. It is 5 months old now and the dealer thinks I am making things up. I did have it tested for VOC and it came back with severe levels. Do you have any sources that you can share that I can send to the dealer. Appreciate your work you have done in this area.
Hi Liz i have the same problem with my new corsa. it makes me sick and dizzy every time i get in it and Vauxhall and the dealer think it’s me making a fuss. Every day i drive it the toxins build up until im so dizzy i can’t stand up. they had my car back and i drove another corsa a month older with no problem . they say put charcoal in .i’ve tried airing it out every evening but it still doesn’t help
Deniz Strenski says
How do Honda Pilots rate 2018-2019? Thank you, D
Thanks Corinne! My partner is thinking of getting a Subaru Forester 22 Wilderness (we live in the mountains, and on a steep mountain road that gets icy), but I won’t have to get in it for 2 years. She said Subaru phased out PVC recently. Are Subaru’s much worse than Hondas for offgassing (it took 2 years for me to tolerate a Honda Pilot 2020, and wondering if the Subaru would take a lot longer than that or be similar). Thanks!
I don’t know about the Forester, but we just purchased the 2022 Outback. In my opinion, the outgassing is very bad. My wife is very sensitive to odors, and she is having a hard time with it. It even bothers me. Fortunately, we only use the car two or three times a week. Right now I’m going to leave the car out in the sun when I can, and take it for a daily ride with the heat on high and windows slightly open so that the interior heats up and gets blown out. We are talking about getting it detailed, however I’m concerned about the chemicals that hey would use and that a lot of people do not get it when it comes to being sensitive to odors or chemicals, so even if the detailer says that they know what they are doing in this regard, I question if they really know what they are doing.
Thank you for this. I purchased anew car this summer. It had low VOC and I was able to air it out well with the windows down the first few months. However, now that I am using the heater, there is a scent coming from the vents. It is like a dryer sheet scent. Is there something you or your readers would recommend to filter the scent as it comes out of the HVAC vents? .Thank you!
interesting i havent seen that before. they might have added a scented spray in the vents. You might try spraying hydrogen peroxide through from the air intake. See the post on decon mold from car for how to do it.
Change the cabin air filter. A lot of cabin air filters are now made with/by Febreeze. (!!!) You’ll have to search for a non-Febreeze cabin air filter. Or, perhaps DIY with another filter.
Nice article. Thought-provoking and valuable Information. You do have some incomplete sentences (fragments) and never explained what the initials “VOC” indicate (customarily done when initials/abbreviations are first used in a writing). Nonetheless, your article covered a lot of good ground. Thanks!
VOC – volatile outgassing chemicals
poisonous toxic chemicals and gassed from materials outgassing and breaking down. look up plastic shower curtain outgassing for a really good understanding and explanation.
Hello! I am desperate for a little insight here as we have to make a decision on the car we are purchasing in the next couple of days. I am careful about what chemicals I expose my son to as he has asthma and I really don’t want to make it worse, plus we try to avoid toxic chemicals. We are in the market for a used vehicle we can use for off-roading and family trips. We currently are considering a 2011 Land Rover. The ecology website says that cars made in Europe have higher amounts of PVC but lower amounts of flame retardants. So I’m guessing the Land Rover has more PVC in it. Is this a concern after this many years? Would the PVC be off gassed by now? I could switch gears and look at the Honda Pilot however they are not a great fit for what we need. I guess what I’m asking is if you think the possibly higher amount of PVC in the Land Rover would be a concern after this many years? Thanks so very much for any help you can offer me!
Martinique Edwards says
Hi Corinne. I love reading your articles; they integrate a lot of good information! May I ask how do you research these topics, via Google searches and/or through particular databases? I too am beginning to review the literature about these topics. Thank you!
Thank you. This article has a lot of the sources listed throughout. There is more information here on what kind of information I use https://www.mychemicalfreehouse.net/about-this-blog
Thank you for this excellent article. I have difficulty breathing when I’m in hot cars. During the summer months it requires me to use an inhaler. We are currently in the market for a new SUV. Do you have a current list of cars having the least amount of interior toxins? I have seen the 2012 study but nothing more current.
Thank you for any help you can give me on this matter.
I don’t believe anyone has done a study more recently.
Ralph Morewitz says
Thank you for your recommendations. Both my wife and I are very sensitive to chemical smells. Last week we test drove a 2021 Hyundai Santa Fe. Afterwards my wife got the spins and could barely stand. Saturday (12/26/2020), we test drove an Acura RDX and I felt nauseous afterwards. Yesterday, test sat an Audi and I felt “off”. Today, we both sat in a VW Tiguan and were sort of OK, but the smell coming from inside an Atlas crossover was so bad, I could not get in. I got a mild but enduring sinus headache from it. As they say “results may vary,” So far in our car search, we have not had problems with either a Mercedes GLC or a Toyota Venza. My next step is to order the E. L. Foust aircleaner (we have used their big ones for years in our house).
Thank you for the report!
Hi! Did you ever find a car that works for you?
Thanks for the post, it helps review what we will be doing soon to off gas our new car. We were extremely lucky to get one of Canada’s last 2019 models that was at the Subaru Headquarters as a demo in their parking lot but not one people with scented clothes sat in. That big detail was a win as I did not have to worry any clothes’ detergent was transferred, even if the seats were covered with plastics, I know I would still detect it. Worth asking which car wasn’t a demo and just sat on a lot. We were pleasantly surprised at how little it smelled. Those 2019 were first out in the Fall of 2018, we got the last one in the country Jan 2020 to give you a timeframe. Those were an exception because usually they were sold out by July.
Other tips we used during the buying process that I would suggest to help speed up the off gassing: we wanted beige seats as black dyes are especially harsher for me and many black dyes never off gassed either. Also, it turns out light interiors are less sought after so that’s a win for us!. We had them put on the contract that no detailing would be done to the car. I had printed a big friendly yellow reminder inside that we left on the dash for anyone just in case the note not to use any products or vacuum was not communicated to all staff. My husband called back to make sure directions were followed and didn’t sign the final papers until he smelled the car again.
For off gassing now that we have it: on nice days without wood smoke, we off gas it with the windows down, fully in the sun. The sunroof is also another good way to let air out. All carpets are outside for now, except the driver’s including the summer ones. We put an alarm to make sure we don’t forget it overnight. When my husband goes in town, he airs it out and uses recirculate only when there are diesel trucks around. When bug season is here, we will put the AllerAir MCS air purifier in there, too.
I hope those extra tips will help someone. We were lucky to work with a dealership who is used to people like us and such requests as we are in a rural community where fragrances aren’t liked.
thank you for sharing!