more than one-tenth of the global population (780 million) still
relied on sub-standard drinking water sources in 2010. Lack of
sanitation is an even larger concern. An estimated 2.5 billion people
are still without improved sanitation, and sanitation coverage is
below 50% in many countries of Sub-Saharan Africa and Southern
Asia. Consequently, millions of people die annually (3900 children
per day) from diseases transmitted through unsafe water or human
excreta (Shannon et al., 2008).