According to the study published Tuesday in the Proceedings of the National Academy of Sciences, breathing polluted air causes a "steep reduction in verbal and math tests scores."
Researchers at the International Food Policy Research Institute (IFPRI) examined data from the national China Family Panel Studies longitudinal survey, mapping the cognitive test scores of nearly 32,000 people between 2010 and 2014 against their exposure to short and long-term air pollution.
Researchers found that both verbal and math scores "decreased with increasing cumulative air pollution exposure," with the decline in verbal scores being particularly pronounced among older, less educated men.
"The damage air pollution has on aging brains likely imposes substantial health and economic cost, considering that cognitive functioning is critical for the elderly to both running daily errands and making high-stakes economic decisions," study author Xiaobo Zhang of Peking University said.
Cognitive decline or impairment, which could be caused by air pollution according to the study, are also potential risk factors in developing Alzheimer's disease or other forms of dementia.