Physico-chemical properties of sediments governing the bioavailability of heavy metals in urban waterways

Bioavailability is a critical facet of metal toxicity. Although past studies have investigated the individual role sediment physico-chemical properties in relation to bioavailability heavy metals, their collective effects are little-known. Further, limited knowledge exists on contribution nutrients bioavailability. In this study, influence sediments, including total organic carbon (TOC), phosphorus (TP), nitrogen (TN), cation exchange capacity (CEC), specific surface area (SSA), and mineralogical composition reported. The weak-acid extraction method was used measure Cd, Cr, Cu, Ni, Pb Zn as potentially bioavailable fraction sediments an urban creek. results confirmed that Cu has strong selectivity for matter (r = 0.814, p < 0.01). Cr influenced by either mineralogy, nutrients, CEC or SSA. Zn, Ni showed affinity mineral oxides, though preferred binding positions were with particularly 0.794, 0.809, 0.753, 0.01, respectively). adsorption Cd strongly competition other metals its weakly ion (CEC: r 0.424, study indicate compounds can elevate due complexation reactions. Generally, estuarine more favourable weakly-bound metals. This concerning estuaries generate high biogeochemical activity economically important.