Risk assessment of eight metals and their mixtures to aquatic biota in sediments with diffusive gradients in thin films (DGT): a case study in Pearl River intertidal zone

Abstract Background The ecotoxicological risk posed by metals and their mixtures in sediments depends on bioavailability. Many methods for evaluating the bioavailability of sediments/soils are time-consuming expensive, frequently result equivocal outcomes. diffusive gradients thin films (DGT) technique is a good measure that can avoid above drawbacks. Therefore, more effective approaches to this method should be developed focus metal No studies have been conducted using DGT assess aquatic biota sediments. This study therefore first attempt sediment toxicity based technique. intertidal zone Pearl River Estuary selected as case study. Results bioavailable (DGT-labile) concentrations range follows (μg/L): Cd, 0.34–3.62; Pb, 1.35–1.92; Ni, 0.67–92.83; Cu, 0.74–10.30; Zn, 28.60–296.94; Co, 0.03–58.85; Fe, 7.23–4539.36; Mn, 19.40–6626.83. quotient (RQ), which ratio between measured environment (MEC) predicted no-effect concentration (PNEC), evaluate single risk. RQ summing up MEC/PNEC ratios (RQ ) sum toxic units STU used mixture. TheRQ values Mn significantly exceed 1, indicating adverse effects not negligible. Regarding mixtures, both 62.45 743.48, revealing possible has already occurred area. Conclusions two DGT-labile suitable estimate