Motorcycles emit 'disproportionately high' amounts of air pollutants

Dec 19, 2005

Motorcycles collectively emit 16 times more hydrocarbons, three times more carbon monoxide and a “disproportionately high” amount of other air pollutants compared to passenger cars, according to a Swiss study to be published in the Jan. 1 issue of the American Chemical Society’s journal Environmental Science & Technology.

The study, by Ana-Marija Vasic and Martin Weilenmann of the Swiss Federal Laboratories for Materials Testing and Research, found both two- and four-cycle motorcycle engines emitted significantly more of these pollutants than automobile engines.

Particularly worrisome are the high levels of hydrocarbons emitted by Japanese, German and Italian two-wheelers, according to the study. Some hydrocarbons have been linked to global warming, while others are suspected of being carcinogenic. Motorcycles aren’t a primary means of transport in most developed countries, the authors note. As a consequence, they say, “the importance of [motorcycle] emissions has been underestimated in legislation, giving manufacturers little motivation to improve aftertreatment systems.”

Until recently, for instance, U.S. emission standards for highway motorcycles hadn’t been updated in 25 years, despite the fact that these vehicles produced more harmful exhaust emissions per mile than cars or even large sports utility vehicles, according to the Environmental Protection Agency. However, a new EPA rule, which goes into effect in January, will require manufacturers to reduce combined emissions of hydrocarbons and nitrogen oxides in motorcycle exhausts by 60 percent. When the rule takes full effect in 2010, the EPA estimates it will reduce emissions of these pollutants by about 54,000 tons a year, and save approximately 12 million gallons of fuel annually by preventing it from evaporating from fuel hoses and tanks.

Source: American Chemical Society

Explore further: Mapping the world's linguistic diversity—scientists discover links between your genes and the language you speak

Related Stories

Sunfire, Audi en route to synthetic fuel of future

Apr 28, 2015

How are scientific minds doing in coming up with a synthetic fuel as a viable alternative to petroleum? For some engineers, this is a long-held dream they refuse to dismiss. A Dresden-based company, sunfire, ...

Fracking may affect air quality and human health

May 13, 2015

People living or working near active natural gas wells may be exposed to certain pollutants at higher levels than the Environmental Protection Agency considers safe for lifetime exposure, according to scientists ...

Recommended for you

Lady, you're on the money

20 hours ago

So far, women whose portraits appear on U.S. money have been a party of three. Excluding commemorative currency, only Sacagawea, Susan B. Anthony and Helen Keller appear on coins in general circulation, according ...

Old World monkey had tiny, complex brain

22 hours ago

The brain hidden inside the oldest known Old World monkey skull has been visualized for the first time. The creature's tiny but remarkably wrinkled brain supports the idea that brain complexity can evolve ...

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.