The gold and silver each amounting to around 1.5 million Swiss Francs (1 million US Dollars) a year is lost via effluents and sludge from wastewater treatment plants in Switzerland.
Gold concentration in sludge
Platinum concentration in sludge
Annually the Swiss are drained into sewerage: 3000 kg of silver, 1070 kg of gadolinium, 1500 kg of neodymium, 150 kg of ytterbium.
The concentrations of 69 elements in digested sewage sludge and effluent samples from 64 municipal wastewater treatment plants as well as in major rivers in Switzerland.