Water is life – and life on earth is linked to water. Our existence is dependent on water, or the lack of it, in many ways, and one could say that our whole civilization is built on the use of water. This article examines the influence of water on public health throughout history. Farming and the development of settlements lead to the beginning of the problem that faces mankind  today – how to get drinkable water for humans and cattle and how to manage the waste we produce. The availability of water in large quantities has been considered an essential part of civilization throughout the different periods: Roman baths needed a lot of water, as do the water closets and showers used in current Western civilization. The importance of good quality drinking water has been established for years. However, the importance of proper sanitation was not understood until the 19th century.

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. 

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).