The actual study is linked early in the article here: (http://www.pnas.org/content/early/2018/08/21/1809474115 http://www.pnas.org/content/early/2018/08/21/1809

The actual study is linked early in the article here: (http://www.pnas.org/content/early/2018/08/21/1809474115 http://www.pnas.org/content/early/2018/08/21/1809474115) Quoting: > ... Cutting annual mean concentration of particulate matter smaller than 10 μm (PM10) in China to the Environmental Protection Agency’s standard (50 μg/m3) would move people from the median to the 63rd percentile (verbal test scores) and the 58th percentile (math test scores), respectively. The damage on the aging brain by air pollution likely imposes substantial health and economic costs, considering that cognitive functioning is critical for the elderly for both running daily errands and making high-stake decisions.