Smog is heavy in Hong Kong
A blanket of smog enveloped central Hong Kong on Thursday as air pollution hit a record high for 1999. The roadside air pollution index, which tracks nitrogen dioxide levels, registered 134, a level
A blanket of smog enveloped central Hong Kong on Thursday as air pollution hit a record high for 1999. The roadside air pollution index, which tracks nitrogen dioxide levels, registered 134, a level