WHO GUIDELINES AND NATIONAL STANDARDS FOR REUSE AND WATER-QUALITY

Guidelines for reuse and drinking water quality are based on scientific research and epidemiological findings, and as such provide guidance for making risk management decisions related to the protection of public health and the preservation of the environment. Water quality standards are legal impositions enacted by means of laws, regulations or technical procedures, which are established by countries by adapting guidelines to their national priorities and taking in account their technical, economical, social, cultural and political characteristics and constraints. Several examples are presented with the objective of differentiating standards from guidelines, and to show how countries have been adapting WHO guidelines to their situations in order to produce national standards on drinking water quality, and for the use of treated wastewater for crop irrigation.