Lots of bad air blows in from elsewhere

Preliminary data show unhealthy soup of PM2.5 circulating freely

A majority of China's provinces experienced air pollution that blew in from neighboring regions in 2015, but in Hainan, the island province, it amounted to as much as 72 percent of pollutants, according to preliminary results from a national think tank on environmental issues.

Last year, Hainan only generated 28 percent of its own PM2.5, fine particulate matter hazardous to human health. The bulk of it came from neighboring provinces - 20 percent from Guangdong, for instance - a report from the Chinese Academy for Environmental Planning found.