What type of vehicle is the most polluting?

In the car field, BMW performs the best emissions test. Honda and Volvo are more likely to pass the test than others, but are not regular. The bottom is Hyundai, Mitsubishi, Chrysler and GM.

The researchers obtained this result after analyzing data from nearly 4 million cars and trucks that underwent government emissions tests in Illinois, Maryland and Massachusetts (USA).

Accordingly, the structure of the car largely determines the ability to cause environmental pollution.

In the field of trucks, Honda, Toyota and Nissan lead the leaderboard. Ford cautiously ranked fourth. Chrysler and Mitsubishi often fell to the bottom of the table.

"There are a few factors that determine the level of pollution of trucks and cars, and manufacturers are a significant factor," said co-author of Ohio State University Jean-Michel Guldmann. "Some car manufacturers are cleaner than others."

Researchers also recognize the following trends:

• Poorly maintained cars are more "broken" .
• Increasing fuel efficiency in both cars and trucks helps reduce emissions.
• The longer the distance traveled, the greater the emission rate.
• The older the car, the easier it will be to slide the test because the rate of equipment and engine damage is much higher, making the emission increase.
• On average, spring and summer cars discharge pollutants less, possibly due to changing atmospheric conditions, and changes in fuel rates of oil refining facilities.

Life expectancy is also a major determinant of emissions. On average, a car produced in 1985 released 38 times more CO than life in 2001. Toyota has the least difference between new and old models, because of its old cars themselves. This has also been less polluting. Other companies such as Honda, Nissan and Hyundai have significant differences between generations, with older cars emitting more and more emissions.

T. An (according to LiveScience)