River pollution
Pathogenic pollution
Water pollution is a major global problem which is the leading cause of worldwide deaths and diseases. An estimated 580 people in India die of water pollution related illness every day. Water is typically referred to as polluted when it is impaired by anthropogenic contaminants and does not support a human use.
Pathogenic water pollution is usually caused by microorganisms. Many types of microorganisms are found in sewage water that is let out into the rivers. Microorganisms such as bacteria, viruses, protozoa, cause serious diseases such as cholera and typhoid.
Industrial and agricultural work involves the use of many different chemicals that can run-off into water and pollute it.
Metals and solvents from industrial work can pollute rivers and lakes. These are poisonous to many forms of aquatic life and may slow their development, make them infertile or even result in death.
Pesticides are used in farming to control weeds, insects and fungi. Run-offs of these pesticides can cause water pollution and poison aquatic life. Subsequently, birds, humans and other animals may be poisoned if they eat infected fish.
Petroleum is another important form of chemical pollution that usually contaminates water through oil spills when a ship ruptures. While oil spills usually have only a localised affect, it can spread for miles. The oil can
cause the death of many fish and stick to the feathers of seabirds causing them to lose the ability to fly.
Chemical pollution
