提供一篇科技文章的摘要，摘要不超过100个词。
New study suggests that air pollution from cars and trucks may be responsible for the loss of intelligence among millions of people worldwide. Researchers found that high levels of air pollutants called particulate matter, including tiny particles called PM2.5, led to significant drops in test scores in language and arithmetic, with the impact being most pronounced among elderly men. The study underlines the growing evidence that air pollution not only harms our health but also influences our cognitive abilities.