South China Morning Post
> You're choking: Where particulate matter comes from
You're choking: Where particulate matter comes from
PUBLISHED : Monday, 24 March, 2014, 2:39pm
UPDATED : Monday, 31 March, 2014, 7:46am
Air pollution has long been a problem in Hong Kong, particularly the heavy smog that always seems to linger in the winter months. Here we examine how the tiny pollutants affect our health.