House and buildings with lead-based paint can cause lead poisoning that can make you anemic, weak, and lose your appetite.

(a)  

When there is little wind, and high traffic congestion, a combination of smoke and fog called smog is likely to develop that causes breathing problems.

(a)  

Dirty hand can lead to parasitic worm infections.

(a)  

When you eat fish that came from polluted water it can cause diarrhea.

(a)