Study finds gold and silver in Swiss sewage system

2 months ago kakp2 Comments Off on Study finds gold and silver in Swiss sewage system

A gold rush has apparently hit Swiss sewage systems, where more than 40kg of the precious metal is lost annually, a new study has revealed.

Three tons (3,000kg) of silver and 43kg (95lb) of gold are lost from wastewater treatment plants in Switzerland every year, according to the new study.

While that amount of gold and silver is worth three million francs (£3.2million), researchers say recovering the metals from the sewage systems would not be economically worthwhile.

The study , commissioned by the Swiss Federal Office for the Environment and led by environmental chemists from Eawag, looked at metals disposed of in 64 Swiss wastewater treatment plants

The study , commissioned by the Swiss Federal Office for the Environment and led by environmental chemists from Eawag, looked at metals disposed of in 64 Swiss wastewater treatment plants

The study , commissioned by the Swiss Federal Office for the Environment and led by environmental chemists from Eawag, looked at metals disposed of in 64 Swiss wastewater treatment plants

The study, commissioned by the Swiss Federal Office for the Environment and led by environmental chemists from Eawag, evaluated elements found in sewage sludge from 64 wastewater treatment plants across Switzerland.

Trace amounts of elements including gold, silver and copper are used in the tech and medical fields, where they contribute to alloys, coatings, paints and more.

A large portion of the elements enter wastewater in regions where refineries and factories are located, researchers found.

Along with gold and silver, researchers found other rare metals including gadolinium, used in appliances; neodymium, used in magnets; and ytterbium, used in medical tools.

Concentrations of the elements varied in wastewater systems across Switzerland.

Trace amounts of elements including gold, silver and copper are used in the tech and medical fields, where they contribute to alloys, coatings, paints and more.

Trace amounts of elements including gold, silver and copper are used in the tech and medical fields, where they contribute to alloys, coatings, paints and more.

Trace amounts of elements including gold, silver and copper are used in the tech and medical fields, where they contribute to alloys, coatings, paints and more.

Ruthenium, rhodium and gold were found in the Jura region, where the watchmaking industry is widespread.

Elevated levels of Arsenic, which are believed to be geogenic, were found in parts of Graubunden and Valais.

In Ticino, researchers found high concentrations of gold, presumably due to the presence of several gold refineries in the area.

Researchers said in a press release, however, that the recovery of metals from the sewage sludge is not economically worthwhile.

For example, they said, the total amount of aluminium and copper found are equivalent, respectively to 0.2 and 4 per cent of annual imports in Switzerland.

The concentrations do not pose risks to the environment and lay below ecotoxicological limits, researchers said.