Stream water sampling for measurement of dissolved and nanoparticulate metals, and measurement of several physico-chemical water parameters (dissolved oxygen, water temperature, conductivity, pH) was conducted on 18^th March 2025, during rainy period with increased water-levels and water discharges.

Twelve urban streams were encompassed, six on the eastern slopes (Čret, Gračanec, Bliznec, Štefanovec, Reka, Trnava) and six on the western slopes of the Medvednica mountain (Črnomerec - Mikulići, Črnomerec - downstream from Clinical hospital Sv. Duh, Kustošak, Vrapčak, Dolje, Dubravica).