The 2011 Mitsubishi Outlander Sport had the highest levels of toxic chemicals.

That new car smell can be appealing. You can even buy air fresheners in a new car scent. But researchers say that you’re actually breathing in toxic materials that can be harmful to your health.

A recent study by the Ecology Center, an Ann Arbor, Mich.-based nonprofit environmental organization, says that chemicals like lead and chlorine are found in many new vehicle interior materials and parts, like on the armrests, steering wheel, dashboard and seats.

CNET says, “These chemicals are used to make plastics flexible, make fabrics fire-resistant, and contribute to that ‘new car smell.’ But they're also associated with birth defects, impaired learning, liver toxicity, and cancer.”

Jeff Gearhart, research director at the Ecology Center, says in a statement, “Research shows that vehicle interiors contain a unique cocktail of hundreds of toxic chemicals that off-gas in small, confined spaces.” And when the interior of the vehicle heats up while it’s parked in the sun, for example, the high temperatures break down those chemicals. “Automobiles function as chemical reactors, creating one of the most hazardous environments we spend time in,” Gearhart says.

Some new vehicles have more toxic materials than others. The Ecology Center tested more than 200 new vehicles from the 2011 and 2012 model year and found that the 2011 Mitsubishi Outlander Sport had the highest amount of toxic chemicals. The 2011 Chrysler 200 SC and Kia Soul also ranked at the bottom for having high amounts of chemicals. The 2012 Honda Civic had the lowest amount of toxic chemicals, followed by the 2011 Toyota Prius and 2011 Honda CR-Z.

“The good news is overall vehicle ratings are improving,” the Ecology Center says. “The best vehicles today have eliminated hazardous flame retardants and PVC. Today, 17 percent of new vehicles have PVC-free interiors and 60 percent are produced without BFRs.”

If eco-friendly new car interior materials are important to you when shopping for your next new car, the Ecology Center says to look at cars like the Civic. The Civic doesn’t use any bromine-based flame retardants in any of its interior materials and uses PVC-free interior fabrics and trim. Additionally, the Civic also has low levels of heavy metals.

“Overall, Ecology Center has rated Honda as the top automaker with respect to healthy car interiors every year since 2007, while Hyundai-Kia was ranked the lowest during the last two years, according to the study,” MSNBC reports.

Many car shoppers aren’t likely to ask the dealer how much lead is in the seat materials, but studies like this can help you choose a new vehicle that’s more eco-friendly and less toxic than others.

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