nondrinkable

Nondrinkable is an adjective describing water or liquids that are not suitable for human consumption. In practice, this label is used when contaminants or conditions make the liquid unsafe to drink, even though it may be usable for other purposes.

Common reasons for nondrinkability include pathogenic microorganisms (bacteria, viruses, parasites), chemical pollutants (lead, arsenic, pesticides), elevated salinity, high turbidity, or radioactivity. The determination of nondrinkability is typically based on health-based guidelines or regulatory standards that specify allowable concentrations and exposure limits.

Applications of the designation include public water advisories, labeling on containers, and disaster or environmental reporting. Nondrinkable water may still be suitable for non-consumptive uses such as irrigation, industrial processes, firefighting, or toilet flushing, depending on local guidelines and safety considerations.

Regulatory language often prefers terms such as non-potable or not potable for labeling and signage. The form nondrinkable may appear in informal instructions, emergency kits, or educational materials.

See also: potable water, non-potable water, water quality, contamination.