Air pollution makes people less happy. Literally

If you live in a city with high levels of air pollution, you may well be unhappy about it. Turns out that you may be unhappy in a very literal sense too.

According to a team of researchers at the Massachusetts Institute of Technology in the United States, people in China, which has some of the worst air pollution levels in the world, chronic levels of air pollution adversely impact people’s level of happiness.

“Pollution has an emotional cost,” stresses Siqi Zheng, an associate professor in MIT’s Department of Urban Studies. “People are unhappy, and that means they may make irrational decisions.”

Even as China’s economy is booming with more and more people leading more prosperous lives, levels of happiness have not been keeping up, Zheng’s team explains in a paper.

One reason is that economic growth has come with chronic social and environmental problems in teeming urban metropolises, including constant air pollution. To protect themselves, locals try to spend less time outdoors and resort to stratagems like wearing cumbersome face masks.

On especially polluted days, the researchers say, many people tend to engage in more impulsive and risky behavior perhaps because of anxiety of depression triggered by their discontent with their toxic environment.

To try and quantify people’s perception of their happiness levels in the face of bad air, the researchers relied on real-time data gleaned from social media with the aim of tracking how daily levels of airborne ultrafine particulate matter impacted people’s happiness in 144 Chinese cities. “Social media gives a real-time measure of people’s happiness levels and also provides a huge amount of data, across a lot of different cities,” Zheng explains.

High concentrations of tiny airborne particulate matter, such as micro-size PM2.5 particles, are exceedingly dangerous to people’s health during longer exposure to them. The researchers then set out to see how people generally reacted on days with especially high levels of toxic air based on 210 million geotagged tweets gathered from China’s largest microblogging platform called Sina Weibo.

What they found was “a significantly negative correlation between pollution and happiness levels.” Women were especially sensitive to higher pollution levels, and so were people with higher incomes, because they may well be more concerned about their health.

In general, when the air is particularly toxic, people’s subjective sense of wellbeing diminishes, the experts say. Perhaps that should not come as a surprise, however, to many of us who have been forced to endure chronically high levels of noxious airborne pollutants.