VOA标准英语2011-Pollution Might Cloud Minds of Older Men

（单词翻译）

New research finds a link between vehicle emissions² and cognitive³ function in older people.

People who live in polluted cities can see the grit⁴ and dirt produced from vehicle engines but some of the most damaging emissions are only now starting to be understood. They're ultrafine particles that are way too small to be seen. Hundreds of these particles, placed side by side, match the width of a human hair and are primarily produced by combustion⁵ in diesel⁶ engines.

Harvard doctoral researcher Melinda Power says we now understand that ultrafines are a more significant problem than emission¹ gasses or those large particles that make your skin dirty.

"They can actually get absorbed in through the surface of the lung, into your body, or they can travel straight up the olfactory⁷ nerves into your brain," says Power. "And so these particulates⁸ because they are so small have the potential to not only enter the body but then interact with the cellular⁹ machinery¹⁰ of the body as well."

To study the effects of this pollution on seniors and their cognition, Power took data from a study of older men who live in and around the Boston area. In addition to collecting health information, researchers gave the men tests that measured their thinking.

Then Power matched the data about the men to their addresses.

"People who live next to major roads are going to have much higher exposure to traffic related particulates than people who live further away," says Power. "The largest determinant of indoor air quality is outdoor air quality. So all of our houses have some exchange of air with the outside and what's outside will end up inside."

Power found that a doubling of traffic pollution was associated with having a lower scores on cognition tests, even lower than what would be expected with normal aging.

She says there are only one or two other studies that look at the association between cognition and pollution. But she says she feels confident she's identified an important phenomenon that needs to be examined more thoroughly¹¹. She plans several more studies to do that.

Power's paper is published in the journal Environmental Health Perspectives