Air pollution 'makes people feel unhappy'
Air pollution is not just bad for health - it also makes people unhappy, a new study has shown.
Researchers at MIT in the US and the University of Beijing in China discovered a direct link between the amount of particulates in the air and happiness.
Research has previously shown air pollution is damaging to health, cognitive performance, labour productivity and educational outcomes.
But air pollution also has a broader impact on people's social lives and behaviour, according Siqi Zheng, associate professor in MIT's Department of Urban Studies.
"Pollution also has an emotional cost," said Dr Zheng. "People are unhappy, and that means they may make irrational decisions."
Researchers used pollution data from 144 Chinese cities and monitored general happiness of urban dwellers by looking at the mood using 210 million messages from China's largest microblogging site, Sina Weibo. Every increase in pollution above a healthy level brought happiness down by 0.04 points out of 100.