In the USA, the Environmental Protection Agency (EPA) has drinking water regulations for more than 90 contaminants. The Safe Drinking Water Act (SDWA) includes a process that EPA must follow to identify and list unregulated contaminants.

This process may lead to the development of a national primary drinking water regulation (NPDWR) in the future. EPA must periodically publish this list of contaminants (the Contaminant Candidate List, CCL), and decide whether to regulate at least five or more contaminants on the list (regulatory determination). A regulatory determination is a formal decision on whether EPA should initiate a rule making process to develop a NPDWR for a specific contaminant. EPA considers three criteria when making a determination to regulate:

• The contaminant may have an adverse effect on the health of people.
• The contaminant is known to occur or there is a high chance that the contaminant will occur in public water systems often enough, and at levels of public health concern.
• In the sole judgment of the Administrator, regulation of the contaminant presents a meaningful opportunity for health risk reductions for persons served by public water systems.

In the United States, the Agency for Toxic Substances and Disease Registry (ATSDR) is a federal public health agency that forms part of the Department of Health and Human Services, and its function is to protect communities from health hazards related to the exposure to dangerous substances, and to conduct studies on water consumption. In accordance with its public information strategy, the agency publishes information sheets regarding exposure to hazardous substances and their effects on health.

In Colombia, the Ministry of Health elaborated the ABECÉ document on water and basic sanitation, which outlines the risks of consuming contaminated water; likewise, the document ‘Towards a Healthy Household, a Living Home,’ the Ministries of Social Protection, National Education, the Environment, Housing and Territorial development and the Ministry of Agriculture included a chapter called ‘Sips of Life. Water for Consumption at Home,’ which explains the risks of using contaminated water.

In the UK, the work of the Drinking Water Inspectorate (DWI) is wide-ranging, covering all aspects of the quality of public water supplies. Closely aligned with its statutory duties, the DWI has responsibility for many other functions.

• Dealing with queries relating to drinking water quality from consumers, organizations, and businesses.
• Provision of advice to ministers and officials on drinking water supply issues, and on parliamentary questions and other queries arising.
• Provision of advice to ministers on private water supplies (i.e. those not supplied by a water company), and related issues.
• Management of Defra’s Water Quality and Health research programme.

Related to these non-statutory duties, the DWI provides information and advice to consumers on the quality of drinking water, including priority contaminants of public health concern, including the following:

• Chlorine
• Cryptosporidium and cryptosporidiosis
• Fluoride
• Lead
• Nitrate
• Pesticides
• Pharmaceuticals
• Taste and odour