Alteration in physical, chemical or biological characteristic of water, making it unsuitable for designated use in its natural state, is ________.
Water pollution can be defined as alteration in physical, chemical or biological characteristics of water, making it unsuitable for designated best use in its natural state.
World Health Organization (WHO) has defined water pollution as inclusion of any foreign material either from natural or other sources into a water body, thereby changing the natural qualities of water and making it unusable for its intended purpose.