Answer:
Air pollution
Positive: China will be carbon neutral by 2060 requires global cooperation.
Negative: Reduced annual emissions by as much as 1.8 billion tons of carbon dioxide and other gases.
Crime
Positive: These behavioral impacts explain a further, smaller portion of the increase in crime. (There's really nothing positive about crime.. but that's the most positive thing I found)
Negative: The male-heavy environment affects boys' behavior.