Water is essential to sustain life, and an adequate, safe and accessible supply must be
available to all. According to the World Health Organization (WHO), “About 2.6 billion people
– half the developing world – lack basic sanitation and 1.1 billion people have no access to any
type of improved drinking source of water.” This results in 1.6 million people dying every year
from diseases attributable to lack of access to safe drinking water and basic sanitation and 90%
of these are children under 5, mostly in developing countries[1]. Microbial contamination of
drinking water contributes to disease outbreaks and background rates of disease in both
developed and developing countries worldwide. Control of waterborne disease is an essential
element of public health policy and an objective of water suppliers[1]. Disinfection is of absolute
importance in the supply of safe drinking water. The destruction of pathogenic microorganisms
is essential and very commonly involves the use of reactive chemical agents such as chlorine,
which is most versatile chemicals used in water and wastewater treatment.
