Nickel is an invisible danger and very often triggers allergies. The skin reacts, itches, burns and turns red. But very high concentrations can also cause intestinal problems or even trigger brain damage.
Nickel usually enters the human body through contact with nickel-containing materials (e.g. jewellery) or through drinking water and food.
Allergists estimate that in Germany about 11% of women and 6% of men suffer from nickel sensitivity. About one in 5 nickel allergy sufferers are estimated to be so sensitive that they also react to nickel in food and drinking water.
Drinking water is life!
Therefore, it must be of such a nature that no harm to human health is to be feared.
Nickel (Ni) also occurs naturally in water and plants as a chemical component in minimal concentrations. However, the nickel concentration in drinking water can be greatly increased by nickel alloys, e.g. in sanitary fittings, pipes or connecting hoses.
The nickel content of the water is also influenced by the pH value of the water, the water temperature, but above all by the length of time the water stands in chrome-plated fittings. Thus, the nickel concentration often increases in the drinking water pipes of a building, especially when the water is stagnant (standstill of the water e.g. during the night, a holiday, etc.) The higher the flow rate, the lower the concentration of nickel in the water.
In the chrome-plating of fittings, nickel is contained as an alloying element, which is responsible for the nickel release in the end product. Depending on the duration of water stagnation in the pipe or in the fitting, nickel can dissolve and thus significantly increase the concentration in drinking water. According to the Drinking Water Ordinance, a limit value of 0.02 milligrams/litre (after long-term use, 3 months) based on an average consumption per week applies today. This means that drinking water and outlet fittings are to be credited with a proportion value of 0.01 milligrams/litre.
The Drinking Water Ordinance as well as the Federal Environment Agency stipulate that certain limit values for chemical substances must be complied with in addition to sterility. In apartment buildings and public buildings, the water quality must therefore be regularly tested chemically and microbiologically. If there is an increased concentration of traces of metal or bacteria, the health authority is informed and the building owner or operator must take appropriate countermeasures at their own expense. However, private house or flat owners can also contact the respective health authority if they suspect an elevated nickel concentration in order to obtain information and advice on the possibility of possible sample analyses.
There is no need for a nickel-chrome coating on a fitting for hygienic reasons. According to DVGW DIN 50930-6, a limit of 20% of the total contact area with drinking water was previously considered permissible. This is no longer tenable today.
This is why, for example, our appliance connection fittings are no longer nickel-plated or chrome-plated on the internal and therefore invisible surfaces. This means that nickel can no longer be released into the drinking water, even when the water is stagnant, and compliance with the limit values is guaranteed.
In accordance with drinking water regulations.
According to the Drinking Water Ordinance, the plumber is also obliged to ensure the safe supply of drinking water. He may only install components that enable compliance with the chemical and microbiological limit values. Otherwise, the installation company can be held liable.
Sources: DVGW/ UBA; HSK Health Department; info sheet Schlösser Armaturen/10-2013