Name three major types of water pollutants, and provide an example of each. explain which classes of pollutants you think are most important in your local area.

Unwanted substances present in water are called water pollutants that cause water pollution. Water pollutants can be of various types such as:
1. Suspended matter pollutants: These are the water pollutants present on the surface of water. These pollutants do not dissolve in water and are found suspended in water. For example, Plastic bags and other plastic products.
2. Chemical pollutants: Metals and solvents from the industries and factories flow in the water bodies and pollute them.For example, pesticides, etc.
3. Microbiological pollutants: These pollutants include bacteria, fungi, algae, etc. Some of these microflora are naturally present in the water and do not cause harm but if their number increases dramatically it affects human health if drunk without treatment.

I think, in my area due to the presence of industries, chemical pollutants are more profound that also leads to the depletion of oxygen in water by increasing the Chemical oxygen Demand (COD). It adversely affects the aquatic living organisms. 

Bacteria have complex internal structures.