Shungite application for treatment of drinking water – is it the right choice?

Shungite is a natural carbon containing material that is widely used in water treatment. Scientific research shows that shungite has good adsorption properties towards various organic compounds and heavy metals, as well as exhibiting antibacterial properties. Unfortunately, at the same time shungite releases various chemical elements into the water, including heavy metals. In this study changes in concentration of various heavy metals during drinking water treatment with one commercial and one non-commercial shungite sample were determined. Also sorption of Cu(II) with initial concentration of 2,500 μg/L onto shungite was investigated. The results showed that various heavy metals like nickel, copper, lead, cadmium, zinc, chromium and arsenic are leaching from shungite into water. Lead and cadmium exceeded the maximum acceptable concentration in drinking water for a few days, but nickel exceeded for up to 2 weeks. At the same time shungite showed good adsorption properties towards copper. Nevertheless, before using shungite in drinking water treatment, it would be advisable to assess the necessity and/or wash shungite with larger volumes of water for a longer period of time than is written in the instructions.