Not put pollutants in in the first place....
On a more serious note: bacteria that will feed off the pollutants is usually your best bet. It is infinitely harder to remove pollutants than it is to put them in.
Probably, awareness and regulations, legislation, perhaps fines for people that don't behave themselves.
YES BECAUSE some pollutants are evaporated with water
Dispersing pollutants in larger volumes of water is called dilution.
no, but it might make it die
Global warming may loft additional water vapor, and might increase temperature in the tropopause. Both increase the rate of decay of ozone. Air pollution usually follows with a decrease in ambient oxygen, and ozone is made from oxygen. Additionally some water vapor, and compounds that are not fully oxidized are added to the atmosphere. Some small portion of these will make it to the tropopause, and reduce ozone a bit. Sunlight will make more, if it can.
Precipitation can carry pollutants in water whereby when moisture rises and mixes with gases from industries thereby condensing and falling back as acid rain may carry the pollutants into water.
Industry, Animals, Agriculture, and Runoff from roads
There are many types of pollutants, and they are classified by the parts of the environment they pollute. The most common are water pollutants and air pollutants.
Pollutants
pollutants
Different pollutants may harm the water cycle. It can make the water acidic.
Detection of pollutants in drinking water spreading awareness about air pollution through posters survey about pesticides and other agrochemicals