Uncontaminated drinking water is hardly available to most of the poor population in the developing or under-developed countries. Water contaminated with bacteria, virus and dissolved ions in excessive amounts cause so many disease.
Contamination of water can be natural or man induced. The reason for the contamination of water is that water is a universal solvent. It leaches away so many chemical compounds from the rocks exposed to it.
Secondly, water makes up more than 70% of the area available on the Earth surface. Life began in the water. So many reactions necessary for the growth and reproduction of life use water as the medium. So it is host to so many bacteria and viruses responsible for diseases.
Countries like Bangladesh and many parts of India where water becomes stagnant in open ponds and shallow wells face the problems caused by water contamination. Due to poverty and lack of resources, people have to drink the water from open ponds and contract the life threatening diseases.
Administration then dug deep wells in search of germ free water. But this gave rise to another even more serious problem: the problem of arsenic poisoning. In the Bangladesh and parts of West Bengal adjacent to Bangladesh, underground water contains a lot of arsenic.
Similarly irrigation of paddy with such water produces rice contaminated with arsenic. It finds its way to the stomachs because the rice is the staple food of Asia.
Innovative Solution to tackle Arsenic Problems
Dr. Abul Hussam, a chemist in Bangladesh, discovered that his own relatives were drinking poisoned water. They live in a district of more than half a million people in a part of Bangladesh called Kushtia. He decided to find a solution.
In 1997, he started measuring the arsenic content of water and developing a filtration system that could remove the toxic arsenic species pumped from tube wells.
Hussam and colleagues made a prototype filter that uses two buckets piled on top of each other. Contaminated water is first poured into the topmost bucket. It passes through a special material called a composite iron matrix, which is a mixture of iron and iron hydroxide. Manganese in the matrix catalyzes the transformation of the more toxic arsenite to arsenate ions. these ions bind to the surface of iron hydroxide particles.
Now this contraption has been made into a filter called SONO FILTER. It is placed on the tuebwell. The output water is free from arsenic. Since then cases of arsenic poisoning have reduced. Many patients have been cured and regained the health by eating more protein rich food along with arsenic free water.