Cyanide in Drinking Water Information:

Properties:

Cyanide is a molecule that consists of one carbon atom triple bonded to a nitrogen atom. This chemical group is present in inorganic compounds like hydrocyanic acid (HCN), forms complexes with a wide range of metal species, and is found in organic molecules referred to as nitriles. Some cyanide-containing species can be identified by their appearance, colouration, or faint, bitter, almond-like odour.1 However, these characteristics are not consistent between species and therefore cannot always be used as reliable indicators of cyanide in drinking water.

Sources:

Cyanide compounds are used in wide range of applications, yet the main route for contamination is through industrial discharge. Mining operations, production of dyes, herbicides, and nylon, electroplating, manufacturing of plastics and metals, and disposal of cyanide-containing effluent can all contribute to increased levels of cyanide in drinking water.2     

Regulations:

The limit for cyanide in drinking water is 50 micrograms per litre (µg/L) in drinking water.

Health/Environmental Concerns:

Ingesting high concentrations of cyanide can cause vitamin B12 deficiencies, lead to thyroid problems, or negatively impact the nervous system.3 Additionally, many cyanide-containing compounds are toxic to humans and are extremely dangerous at elevated concentrations.

Action:

Since cyanide exceedances in drinking water are primarily due to industrial effluent and waste production, it is important that such sources are regulated and monitored. Contact your Water Services Authority if levels of cyanide are above the allowed limit or if you suspect that your water is contaminated. If drinking water makes you ill, contact a doctor right away.

1Toxicological Profile for Cyanide; Agency for Toxic Substances and Disease Registry, U.S. Department of Health and Human Services: Atlanta, GA,

 2Guide to the Parameters in the European Communities. What’s in your water?; S. I. No. 278 of 2007; National Federation of Group Water Schemes: Ireland.

 3Guidelines for Drinking Water Quality. Cyanide in Drinking Water; Vol. 2; World Health Organisation: Switzerland, 1996.