The average American spends 1.5 hours a day in the car. According to a new report released by the Michigan-based Ecology Center, that's 1.5 hours spent possibly inhaling flame retardants, hormone-disrupting plasticizers, and lead. In its annual automotive test, the group tested dozens of cars for those chemicals and found that, though automakers are slowly catching on to the fact that these materials are harmful, many cars still pose an unnecessary threat.
"Many of the chemicals we found exist in products people are exposed to in homes and offices—electronics, furniture, building materials," says Jeff Gearhart, research director at HealthyStuff.org, a project of the Ecology Center. "But vehicles account for over 30 percent of our exposure to these chemicals. It's a very significant exposure source."
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The Best & Worst Cars
The group tested the plastic, fabrics, and foams in 200 top-selling 2011 and 2012 model-year cars for the presence of four things: bromine, which is used to make flame retardants that have been linked to learning disabilities and infertility; chlorine, which indicates the presence of polyvinyl chloride, or PVC, and a hormone-disrupting type of plasticizer used in PVC called phthalates; lead, which is used as a UV stabilizer in many plastics; and neurotoxic heavy metals such as cadmium and mercury.
The 10 most polluted cars were:
1. 2011 Mitsubishi Outlander SP
2. 2011 Chrysler 200 S
3. 2011 Kia Soul
4. 2011 Nissan Versa
5. 2011 Mazda CX-7
6. 2012 Hyundai Accent
7. 2011 Chevy Aveo5
8. 2011 Kia Sportage
9. 2012 VW Eos
10. 2012 Mini Cooper S. Clubman
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The 10 cleanest cars were:
1. 2012 Honda Civic
2. 2011 Toyota Prius
3. 2011 Honda CR-Z
4. 2011 Nissan cube
5. 2012 Acura RDX
6. 2012 Acura ZDX
7. 2012 Audi S5
8. 2011 Smart Coupe
9. 2011 Toyota Venza
10. 2011 Smart Passion
What's Wrong with That New Car Smell
"In general, indoor air is more contaminated than outside air," says Gearhart, "and that's true whether it's offices, homes, or vehicles. Multiple studies have shown that in built environments, whether cars or homes, the primary source of emissions is all our stuff." In cars, that usually means plastics. That "new car smell" we're all so fond of is really just the sweet odor of off-gassing chemicals from plastics, the use of which has increased tenfold since 1960. As the use of plastics in everything from dashboards to seat fabrics has grown, so has the use of plastic additives such as plasticizers, flame retardants, antimicrobials, and antioxidants to protect the plastics from weather extremes and sunlight.
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"Many of these additives are not chemically bonded to plastic, so over time, they're released from it and they bind to dust," he says—and to your windshield. If you've ever wondered how polluted your own car is, just pay attention to the film that shows up on the inside of your windshield. That film is made up of hydrocarbons and petrochemicals that are released by plastic materials, as well as vehicle exhaust, particulate matter from tires and brake pads, and other chemicals that are oily in nature and condense on the glass.
"Cars function as little chemical reactors," Gearhart says, "and our hope is to get safer materials in place and reduce the overall chemical hazards in the base materials in cars." That's happening, sort of. They started doing these tests in 2006, and at that point, no cars were free of PVC and brominated flame retardants, but this report revealed that 17 percent of new vehicles have PVC-free interiors and 60 percent are produced without brominated flame retardants in the car's interior; 8 percent were free of both. "The design cycle on a car can be four to six years," he says. "We started testing in 2006, and now that we have data trends over six years, we're starting to see different shifts in fleets."
The report called out Honda, Ford, and Volvo for leading the way in eliminating toxic materials, and Gearhart says he hopes these companies start making their efforts more visible to the public, so indoor air quality can start to be a factor in buying a car.
Save Your Lungs on the Road
If you aren't in the market for a new Honda Civic, you can still protect yourself from plasticizers and flame retardants while driving.
• Dust and vacuum frequently. Most of the chemicals that off-gas from plastics and foam bind to dust. To keep airborne dust to a minimum, give your car a weekly damp-mopping, and vacuum it out every few weeks.
• Change your air filter. All cars have two to three air filters, including an in-dash filter for your A/C and heating vents. That filter is usually made from cloth or paper, Gearhart says, but you can ask your mechanic to install (or buy for yourself) an activated carbon filter. "If it's just paper or fabric, the filter will just catch particles, but carbon absorbs VOCs," he says, such as phthalates from vinyl materials.
• Recirculate your air. Once you've changed the air filter, use recirculated air when you can and keep the windows rolled up. It may sound counterintuitive, but, "In urban environments, where there are a lot of particulates, driving with the windows closed and the recirculation fan going can reduce particulates in cabins by 2.5 times," he says.
• Use solar shades, or park in the shade. Chemicals are released from plastics and foam more rapidly when they're exposed to heat and UV radiation. Those cause the plastics to break down, and, says Gearhart, "based on some of the chemicals we've studied, we think that some of the breakdown products of the chemicals are more hazardous than chemicals themselves."
• Ventilate your car. Particularly on hot days, before you crank up the engine for your long commute home, open the windows and let the heat escape.