Answer:
On Humans.
People exposed to high enough levels of
certain air pollutants may experience:
Irritation of the eyes, nose, and throat
Wheezing, coughing, chest tightness, and breathing difficulties
Worsening of existing lung and heart problems, such as asthma
Increased risk of heart attack
<u>On </u><u>Environment</u>
<em>Acid rain </em>
<em>Eutrophication</em>
<em>Haze</em>
Space that's my best guess
