[1] Eawag, Swiss Fed Inst Aquat Sci & Technol, CH-8600 Dubendorf, Switzerland
[2] ETH, Inst Biogeochem & Pollutant Dynam, CH-8092 Zurich, Switzerland
[3] ETH, Dept Chem & Appl Biosci, CH-8093 Zurich, Switzerland
[4] EPF Lausanne, Sch Architecture Civil & Environm Engn, CH-1015 Lausanne, Switzerland