Source and distribution of heavy metals in sediment samples from select creeks of the highly urbanized Metro Vancouver Watersheds, Canada

Forty-seven samples collected from 23 creeks in Metro Vancouver, BC, Canada, were analyzed using X-ray Fluorescence Spectroscopy (XRF) to assess how different land use activities affect physicochemical properties in surface water and metal concentrations in sediments. The concentrations of the heavy metals (Ag, As, Ba, Cr, Cd, Cu, Fe, Mn, Ni, Pb, V, Zn) ranged from 2.53–4.11, 7.51–16.27, 98.06–674.21, 22.83–136.68, 2.72–9.10, 6.70–146, 14,516.76–62,755.68, 385.16–5126.12, 11.89–102.12, 5.02–161.83, 50.93–151.63, and 21.40–660.87 mg/kg, respectively, in the study area. High concentrations of some metals were recorded to be above the Canadian Council of Ministers of the Environment Sediment Quality Guidelines, along with elevated contamination indices in some sampling sites. The pH, total dissolved solids (TDS), and electrical conductivity (EC) in surface water samples ranged from 5.50 to 8.27, 14.0 to 410.0 mg/L, and 19.0 to 903.0 µS/cm, respectively, with no discernible relationship between the surrounding land use. Principal component analyses revealed anthropogenic and natural processes enrich the sediments with metals. The geo-accumulation index (Igeo) showed extremely contaminated sediment and a >64-fold increase due to high levels of Ba, Cr, Cu, Fe, Mn, Ni, Pb, V, and Zn. The contamination factors fall in the following sequences: Cd > Ag > As > Pb > Zn > Mn > Cu > Ba > Cr > Ni > V > Fe. Creeks closer to highways with heavy vehicular activities reported significantly higher concentrations of metals. It is therefore important to adhere to the Riparian Areas Protection Regulation Model of the Government of British Columbia, which is vital for maintaining water and sediment quality, stream health, and productivity.