How does Cyanide get into your water?
A Cyanide is a chemical compound that contains the group C≡N.
This group, known as the Cyano group, consists of a Carbon atom triple-bonded to a Nitrogen atom.
Cyanide is a Carbon-Nitrogen molecule which combines with many organic and inorganic compounds.
Cyanides are produced by certain Bacteria, Fungi, and Algae and are found in a number of plants.
Cyanides are found in substantial amounts in certain seeds and fruit stones, e.g., those of bitter Almonds, Apricots, Apples, and Peaches.
Chemical compounds that can release Cyanide are known as Cyanogenic compounds.
In plants, Cyanides are usually bound to sugar molecules in the form of Cyanogenic Glycosides and defend the plant against herbivores.
Cassava roots (also called Manioc), an important potato-like food grown in tropical countries (and the base from which Tapioca is made), also contains Cyanogenic Glycosides.
The most commonly used form, Hydrogen Cyanide, is mainly used to make the compounds needed to make nylon and other synthetic fibers and resins.
Cyanides are used as herbicides.
Cyanides are occasionally found in drinking water, primarily as a consequence of industrial contamination.
Cyanides are generally not persistent when released to water or soil, and are not likely to accumulate in aquatic life.
Some ways to be exposed to cyanide include:
- Eating Cassava, Lima beans, Yucca, bamboo shoots, Sorghum, or Almonds.
- Eating apple seeds, cherry stones, apricot pits, or peach pits.
- Smoking cigarettes.
- Burning plastic.
- Burning coal.
- Inhaling smoke from a house fire.
- Ingesting Acetonitrile-based products are used to remove artificial nails.
- Drinking water, eating food, touching soil, or inhaling air that has been contaminated.
- Exposure to rodenticide or other Cyanide-containing pesticides and herbicides.
Cyanides rapidly evaporate and are broken down by microbes.
Cyanides do not bind to soils and may leach to ground water.
The Health Implications of Cyanide
Short-term: Cyanide has the potential to cause the following health effects when people are exposed to it for relatively short periods of time: rapid breathing, tremors and other neurological effects.
Long-term: Cyanide has the potential to cause the following effects from a lifetime exposure: weight loss, Thyroid effects, nerve damage.
Cyanide may lower vitamin B12 levels and hence exacerbate vitamin B12 deficiency. It has also been linked to an increased incidence of Goitre (Cretinism) in Zaire through effects on Iodine uptake by the Thyroid.
Those with nutritional inadequacy or inborn metabolic errors are particularly vulnerable.
Removal of Cyanide from Cassava in Nigeria.
Chronic effects on the Thyroid and particularly on the nervous system were observed in some populations as a consequence of the consumption of inadequately processed Cassava containing high levels of Cyanide.
This problem seems to have decreased significantly in the West African populations in which it was widely reported following a change in processing methods and a general improvement in nutritional status.
An allocation of 20% of the TDI to drinking-water is made because exposure to Cyanide from other sources is normally small and because exposure from water is only intermittent.
This results in a guideline value of 0.07 mg / Litre (rounded figure), which is considered to be protective for both acute and long-term exposure.
