Water pollution is one of the biggest dangers to human health in developing countries like Pakistan. So many people in Pakistan especially in rural areas have poor access to pure and clean water. Thousands of deaths occur due to water borne diseases each year. Common water borne disease include typhoid, cholera, diarrhea, intestinal diseases, hepatitis, malaria and dengue.
In rural areas major sources of water pollution includes organic sources like human and animal waste while in urban areas in addition to organic waste industrial waste is a major contributor to water pollution.
All over the world, different strategies are being adopted to overcome the problem of water pollution such as use of water filters, UV radiations, distillation and by the use of certain chemicals e.g iodine and chlorine in a process called chlorination. Another important way to purify water is by the use of microorganisms. Microorganisms like bacteria and protozoan are usually considered as harmful and there are many microbes that pollutes to water but at the same time, there are some microorganisms, which can be used for the purpose of water purification.
Microorganisms decompose the water-dissolved contaminants like organic matter and remove the phosphates, nitrates and ammonium particles. For the removal of these contaminants, microorganisms are either mixed with the water or kept near the water distribution source. Most commonly used microorganisms for purification of water include Nitrosomonas bacteria, nitrobacter, bacillus, pseudomonas and Acinetobacter. Elimination of nitrates and ammonium from water is done through the process of nitrification and denitrification by nitrosomonas and other bacteria. Acinetobacter stores phosphate into their cell tissues as polyphosphates and use it as energy source in the absence of oxygen. It is an aerobic bacterium, needs oxygen for its survival and in the oxygen deficient circumstances stored phosphate helps it to survive.
In some countries latest membrane filter are in use containing one celled microorganism attached on their pores. These microorganisms eat the contaminants in water when water is passed through the filter; as a result, water becomes purified. This process of purification by microorganism is called bioremediation.
Like bacteria, fungi can also be used for degradation of pollutants. Fungi produce certain enzymes that are extremely helpful in the degradation of environmental pollutants.
Purification of water by microorganism must be a major area of research for microbiologists in developing countries. Microorganisms can be easily extracted from our surrounding environment therefore, it is a very cheap source for water purification.