Walking through a smog-filled downtown could lead to more than just a nasty cough — it could also harm your cognitive ability, making it harder to verbalize ideas, work through complicated problems, and more, according to a new study published in the Proceedings of the National Academy of Sciences.
After examining 32,000 people over the age of 10 in China between 2010 and 2014, researchers at the International Food Policy Research Institute found that increasing levels of air pollution correlate with lower verbal and math scores.
The effect was especially pronounced among older men, suggesting that long-term exposure to air pollution has a cumulative effect and it could also lead to Alzheimer’s later in life.
These mental consequences are taking a toll on both quality of life and financial stability, according to the authors. When factoring for an entire population, the impact on a country’s economy could be steep.
"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 told CNN.
The authors looked at three pollutants in particular: sulfur dioxide, nitrogen dioxide, and particulate matter smaller than 10 micrometers in diameter.
The implications of the study are widespread — around 95% of the global population breathes polluted air.
Some countries, however, are worse off than others. India, for example, has the world’s 14 most polluted cities, with pollution levels sometimes 20 times higher than recommended limits.
Finland, on the other end of the extreme, has the world’s cleanest air.
Each year, air pollution causes more than 7 million premature deaths, the vast majority of which occur in poor countries, according to the World Health Organization (WHO). The hazards of air pollution build up over time, exacerbating existing health conditions.
Fine particulate matter from pollutants seep into the lungs and cause “stroke, heart disease, lung cancer, chronic obstructive pulmonary diseases and respiratory infections, including pneumonia,” according to WHO.
With so much harm being done by air pollution, the need to address it on a global scale has never been more urgent.