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 causes 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 so many chemical compounds when rocks are 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 lots of water becomes stagnant in ponds and shallow wells face the problems caused by water contamination. Due to poverty and lack of resources, people are forced 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, there is lot of arsenic dissolved in water.
Similarly when such water is used to irrigate the paddy, the rice is contaminated with arsenic and finds its way to the stomachs because the rice is the staple food of Asia. When Hussam discovered that his own relatives—who live in a district of more than half a million people in a part of Bangladesh called kushtia—had been drinking arsenic laced water, he decided to find a solution. in 1997, he started measuring the water’s arsenic content 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. Water is first poured into the topmost bucket, and then 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 which is placed on the tuebwell and the output water is free from arsenic. The arsenic poisoning cases have reduced and many patients been cured and regained the health by eating more protein rich food along with arsenic free water.