Waterborne diseases are caused by pathogenic microorganisms which are directly transmitted when contaminated fresh water is consumed. Contaminated fresh water, used in the preparation of food, can be the source of foodborne disease through consumption of the same microorganisms. According to the World Health Organization, diarrheal disease accounts for an estimated 4.1% of the total DALY (diability-adjusted life year) global burden of disease and is responsible for the deaths of 1.8 million people every year. It was estimated that 88% of that burden is attributable to unsafe water supply, sanitation and hygiene, and is mostly concentrated in children in developing countries.
Simple Options to Remove Turbidity
The health consequences of inadequate water and sanitation services include an estimated 4 billion cases of diarrhea and 1.9 million deaths each year, mostly among young children in developing countries. Diarrheal diseases lead to decreased food intake and nutrient absorption, malnutrition, reduced resistance to infection, and impaired physical growth and cognitive development. Since 1996, a large body of published work has proven the effectiveness of interventions to improve water quality through household water treatment and safe storage (HWTS) at reducing diarrheal disease. However, not all of these interventions remove the turbidity that causes water to look dirty. Although the following options are not proven to reduce diarrheal disease incidence on their own, they can be used to pre-treat water to reduce turbidity before the use of household water treatment products. These options mechanically (through filtration) or chemically (through flocculation and settling of suspended material) remove particles and reduce turbidity. These pre-treatment methods may also increase the efficacy of household water treatment products by removing contaminants that interfere with disinfection and physical filtration processes.
Helminth eggs are the infective agents for the types of worm diseases known globally as helminthiases. Although helminths are pluricellular animals their eggs are microscopic (around 20 to 80 μm for those that are important in the sanitary field) and are contained in variable amounts in wastewater, sludge and excreta. Helminth eggs infect humans through: (1) the ingestion of food crops polluted with wastewater sludge or excreta, (2) direct contact with polluted sludge or faecal material, and (3) the ingestion of polluted meat or fish.
Distillation Treatment and Removal of Contaminants from Drinking Water
Distillation treatment typically removes most of the dissolved materials. In addition, the boiling process kills biological contaminants. Nevertheless, there are certain volatile and semi-volatile organic compounds that may not be removed by distillation (CDPH 2009). Organic compounds that boil at temperatures greater than the boiling point of water (some pesticides) can be effectively removed from the water (MSUE 2003). Organic compounds that boil at temperatures lower than the boiling point of water (ex., benzene and toluene) will be vaporized along with the water. If these harmful compounds are not removed prior to condensation, they will remain in the purified product (MSUE 2003).
Arsenic Contamination In Groundwater In Bangladesh: An Environmental And Social Disaster
Before 1971 (Year of independence from Pakisthan), thousand of people died each year due to water born diseases in Bangladesh. To provide safe water, with help of UNECEF, the Government of Bangladesh (GoB) installed millions of tubewell which ensured safe drinking water to 97% population of Bangladesh. When the people are habituated with tubewell water, then in 1993, the people of Bangladesh discover the silent killer, the Arsenic. It becomes a challenge to an excellent public health success story. This paper has reviewed environmental and social implication of Arsenic in Bangladesh