by Holly Rizzo
vehix.com Ah, that new-car smell. Some people have suggested it should be bottled and sold. If it were, what would the ingredients be?
They would include formaldehyde, naphthalene, carbon disulfide and other tongue-twisting compounds – chemicals linked with cancer, endocrine-system disruptions, and neurologic, immunity and reproductive-system disorders.
Don’t panic. Drivers and passengers will continue emerging intact from new cars. But researchers also continue studying in-car pollutants, manufacturers have begun addressing them, and consumer groups offer guidelines for avoiding them.
Studies of pollution inside cars have been conducted since at least the early 1990s. Early research attempted to find how much exterior pollution, such as tailpipe emissions, made it into the cabin during traffic jams. Roads in Los Angeles and Sacramento, Calif., provided excellent laboratories, with concentrations of pollutants lower inside vehicles driving in carpool lanes but still four times higher than in the air outside the car.
It’s natural that these pollutants would be drawn into the car. But what about substances arising from the materials used to carpet and upholster the interior – the contributors to new-car smell?
An early study found more than 100 volatile organic compounds, or VOCs; polybrominated diphenyl esters from flame retardants; and phthalic acid esters, or phthalates – the vapors arising from carpet, vinyl, foam and adhesive -- inside a 1995 Lincoln Continental. The substances can incite asthma and allergy symptoms, and can lead to cough, headache and even to skin irritation. “The concentrations dropped substantially over a two-month period, but still were readily detectable, and continued to increase from morning to midday as temperatures rose in the car,” according to Environmental Health Perspectives, the journal of the U.S. National Institute of Environmental Health Sciences.
Not much has changed. In 2006, a Japanese study of 101 cars found that each one contained 241 airborne toxins; a 2007 study in Taiwan of 20 new vehicles noted that one sedan contained more than 200 times the level of toxic compounds than is safe to inhale. However, a 2003 study at the University of California, comparing new and old vehicles, found that old cars contained about half the level of VOCs in new cars because emissions fade over time.
What about the interim between brand-new and less-new? The United States doesn’t regulate materials used in car interiors or the emissions from them, but the Japanese Automobile Manufacturers Association agreed to reduce VOCs to those set by the Japanese Ministry of Health, Labor and Welfare rules for homes. Toyota is developing a plastic made from sugar cane or corn to reduce in-cabin VOCs; and Nissan has changed seats, carpets and other interior finishes for its Japan-built vehicles. Ford is certifying some of its vehicles for interior air quality, has developed a soy-based foam and plans to use a natural-based upholstery fabric; Chrysler has incorporated the use of flax and abaca fiber. Many manufacturers are working on replacing parts with alternatives to polyvinyl chloride.
Air flow while driving reduces the levels of organic compounds but introduces more of other pollutants: dust, pollen and mold. To counteract them, DuPont now offers interior air filters that the company claims capture 96 percent of pollutants. Volvo took filtering a step further by pairing a filter with a sensor that detects hydrocarbons and other substances, shutting the air intake when necessary.
How can consumers reduce their exposure to interior pollutants? Here are some tips from the Ecology Center in Ann Arbor, Mich.:
- Buy a model that has sat on the lot for a few months, allowing interior materials to release toxins.
- Park the car out of the sun, because heat releases pollutants from plastics and adhesives.
- Use a sun screen in the car’s windows to reduce the interior temperature.
- Use a HEPA air filter.
The nonprofit center rates vehicles based on the materials they contain. To see how your car stacks up, visit
www.heathycar.org.
What does it all mean for the future of new-car scent? Perhaps less of the aroma a newly minted vinyl and more sweet whiffs of fresh air.