What is Water Pollution
Water pollution takes place when bodies of water, such as rivers and streams, becomes contaminated from a single source. Some of these sources include waste water treatment plants and oil tankers. Water pollution introduces dangerous chemical, physical or biological agents into the water that adulterates and degrades the quality of the water, thus affecting the organisms that depend on the water for survival. In many developing countries, clean drinking water is not readily available. Contaminated drinking water causes about 80% of the diseases in developing countries and kills about 10 million people annually, with the majority of them under the age of 5. A good indicator of the quality of drinking water is the number of coliform bacteria colonies that are present in the water. The World Health Organization recommends zero colonies of coliform bacteria per 100 milliliters of water that is suitable for drinking.
Common Disease Transmitted to Humans from Contaminated Drinking Water
Because of the dearth of clean drinking water in many developing countries, there are many diseases that are commonly transmitted to humans through this affected drinking water. These diseases are transmitted through bacteria, viruses, parasitic protozoa and parasitic worms. These are all considered pathogens, disease-causing agents.
Diseases that can be caused by bacteria in contaminated drinking water include typhoid fever, cholera, bacterial dysentery and enteritis. Typhoid fever can cause diarrhea, severe vomiting, an enlarged spleen, and inflamed intestines and is often fatal if left untreated. Cholera can result in diarrhea, severe vomiting, and dehydration and is also fatal if left untreated. Bacterial dysentery results in much more severe diarrhea, however is rarely fatal except in young children. Enteritis can cause severe stomach pains, vomiting, and nausea, however is very rarely fatal.
The only viral disease that can result is Infectious hepatitis. It can cause permanent liver damage and an enlarged liver but is rarely fatal. Some symptoms include fever, loss of appetite and abdominal pains.
Parasitic protozoa can cause amoebic dysentery. Amoebic dysentery can result in severe diarrhea, headaches, chills and fever. This is probably the most deadly of diseases from polluted drinking water; and if left untreated, it can cause live bowel perforation, abscess or even death.
Parasitic worms can cause schistosamiasis. This can result in abdominal pains, skin rashes, chronic fatigue and anemia.
Pollution of Streams and Lakes
Streams and larger rivers are able to quickly recover from polluting events because of their continuous flow. This continuous flow is able to continually dilute the pollutants that result from surface runoff. However, this is only effective when the flow is continuous, not reduced or diverted, and as long as they are not overloaded with pollutants. However, this process is not effective against slowly degradable and non-degradable pollutants and can then pose as dangers to organisms living there or to those who drink this polluted water.
Lakes are very vulnerable to pollution because of the stratified layers that they have. They undergo very little mixing that ultimately results in the accumulation and magnification of pollutants as well as a reduction in dissolved oxygen. Because of this, lakes receive large amounts of inputs of nutrients that are unable to be diluted. This is called eutrophication. Human activities can accelerate the input of nutrients into a lake, called cultural eutrophication. This is very prevalent in urban and agricultural areas.
In conclusion, the dangers of water pollution associated with lakes, streams, rivers, and other contaminated bodies of water, ultimately affect our drinking water, causing several life-threatening diseases that we need to be aware of.