Potassium is the English name for this element as opposed to the German 'kalium' that was eventually dropped, hence why the chemical symbol is K. Originating from potash, potassium was isolated by Sir Humphry Davy using electrolysis in 1807 and is very chemically similar to sodium, the previous element in group 1 of the periodic table.
Potassium is very reactive, even in air, and reacts to produce potassium peroxide without much exposure time. Potassium is not found in its elemental state since it reacts with water and is only found as a salt in the environment, occurring naturally in minerals and igneous rocks. 95% of global potassium manufacture goes into making fertilizers, useful for increasing the amount of potassium in the soil following crop production.
| Age | Daily Intake (g) | |
|---|---|---|
| 1-3 | 3 | |
| 4-8 | 3.8 | |
| 9-13 | 4.5 | |
| 14+ | 4.7 | |
| World Health Organisation Dietary Recommendations | ||
Potassium is a common element found in the human body, appearing in many different proteins and enzymes. Potassium levels are vital to several bodily functions such as hormone action as well as glucose and insulin metabolism. Potassium is an essential nutrient so recommended daily intake values are provided by the NHS. Insufficient potassium intake is common in EU countries such as Germany and Italy and can lead to hypertension (high blood pressure) as well as other symptoms.
Potassium can be found in all fruits, vegetables, meat, and fish, with some foods such as potatoes and nuts having high concentrations. Eating 11 bananas would provide the potassium intake for one day. Despite being an essential nutrient, excess potassium can stomach pain and diarrhoea.
Potassium is very common in natural waters due to its occurrence in minerals and can occur in drinking water from the use of potassium permanganate as an oxidant in water treatment. It is also sometimes used in home ion exchange filters to exchange calcium and magnesium ions for sodium and potassium, softening the water.
Potassium is rarely found at levels that pose a health risk and the primary source of potassium is in the diet, not drinking water. Potassium used for water treatment causes concentrations relatively low in comparison to water softeners in the home.
Potassium in your drinking water can be detected by the following tests.
Potassium can be reduced or removed from your drinking water using the following methods.
