Nitrate and nitrite are nutrients for plants, which have been used for many years as a fertilizer in agriculture, and also in small gardens, etc. Nitrate and nitrite are convertible with one other, depending on the oxygen content in the water. The cause of health risks is the risk of a reduction of nitrate to nitrite. Such a conversion takes place in the intestines through certain bacteria. Secondly, the salivary glands can, via the blood vessels, reduce stranded nitrate. The current limit for NO3-in drinking water is, according to German drinking water regulations, at 50 mg / l, and according to the Swiss Water Protection Regulations, at 25 mg / l, waters that exceed this limit are, often mixed with low-nitrate water in order to reach this limit. Recently, the first water treatment systems have been built using reverse osmosis or nanofiltration in order for the lower partial demineralization of the nitrate level in drinking water.
