> and measuring the atmosphere in China, which is home to 16 of the 20 most polluted cities in the world. I wonder what the source is on this. I only spent a

> and measuring the atmosphere in China, which is home to 16 of the 20 most polluted cities in the world. I wonder what the source is on this. I only spent a minute Google searching, but the numbers I'm seeing put China WAY below 16 of the top 20.