Scientists have revealed that air pollution may be for a significant reduction in intelligence. Research conducted for the World Health Organization (WHO) in China showed that air pollution was responsible for falls in student scores for languages and . The Chinese study is called, "The of exposure to air pollution on cognitive ". It was published in a journal called, "Proceedings of the National Academy of Sciences". The took place over a of four years. Researchers analyzed verbal and arithmetic tests taken by 20,000 people of all . They said: "Polluted air may impede cognitive ability as people become ."
Researchers say their study is a to the rest of the world, especially to those who live in . The WHO says over 91 per cent of the world population live in with toxic air. Air pollution is the fourth highest cause of deaths worldwide. The researchers discovered that the people were exposed to polluted air, the greater was the to their intelligence. They equated the impact of air pollution to losing a year's of education. For those aged over 60, this could be the of several years of lost education. Researcher Dr Xi Chen warned: "There is no to solve this issue. Governments really need to take measures to reduce air pollution."