LITERATURE REVIEW
2.1 WATER AND WATER SAFETY
Water is essential for the existence of humans and all living things and hence a satisfactory (adequate, safe and accessible) supply must be available to all. Water used for domestic purposes must be clean and not contain any microorganism, parasites and other substances which can pose danger to human health. Safe water supply and sufficient sanitation to secure health are among the essential human rights. However, many people do not have access to safe drinking water and risk to waterborne diseases is a critical public health problem in many developing countries. So securing safe drinking water for all is one of the significant difficulties of the 21st century. In a recent report, close to a billion people mostly living in the developing world do not have access to adequate and safe drinking water (Adedeji et al., 2017; Bekuretsion et al., 2018).