Effects of suspended solids and dissolved organic carbon on nickel toxicity

Abstract

Nickel (Ni) is a common and potentially toxic heavy metal in many fluvial ecosystems. We examined the potentially competitive and complementary roles of suspended sediment and a dissolved organic ligand, humate, in affecting the partitioning and toxicity of Ni to a model organism, Daphnia magna, in both batch and stream-recirculating flume (SRF) tests. Sediments included a fine-grained deposit, montmorillonite, and kaolinite. Survival of D. magna was unaffected by the range of suspended solids used in the present study (8-249 mg/L). However, exposure to suspended solids that were amended with Ni had a deleterious effect on test organism survival, which is attributed to partitioning of Ni into the aqueous phase. At comparable levels of dissolved Ni, survival of D. magna was reduced in tests with Ni-amended suspended solids compared to Ni-only aqueous exposures, suggesting potentiation between these two aquatic contaminants. Addition of humate attenuated toxicity to D. magna in both Ni-only and Ni-amended suspended sediment exposures. These results indicate that organic ligands and suspended solids have important functions in affecting the bioavailability and toxicity of Ni to aquatic organisms and should be incorporated into predictive models to protect ecosystem quality.

Characterization of tannery effluent wastewater by proton-induced X-ray emission (PIXE) analysis to investigate their role in water pollution

“…It has the ability to cross human placental barriers and produces embryotoxicity and teratogenesis (Chen and Lin 1998). Moreover, it is also considered as a toxic metal that can damage many fluvial ecosystems (Cloran et al 2010) by changing the soil composition (Li et al 2010) and water hardness (Deleebeeck et al 2009), which consecutively damage plant roots (Seregin and Kozhevnikova 2009).…”

Toxicological effects of short-term resuspension of metal-contaminated freshwater and marine sediments

“…Uptake from the dissolved phase is the most important route for Zn and Cd bioaccumulation in this organism [53], so an absence of elevated tissue metal concentrations was not surprising. Other studies have shown synergistic effects between particulate and dissolved metals, with bioaccumulation being metal and species specific [8,9,11,12]. Despite high concentrations of metals associated with suspended particles, the metals apparently were not bioavailable and did not elicit adverse effects.…”

“…Suspended particles are often enriched with metals compared with bedded sediments (i.e., not resuspended) and thereby could result in proportionately greater biological exposure if ingested. When combined with aqueous exposure to metals, exposure to contaminated suspended particles can increase lethal and sublethal toxicity compared with aqueous‐only exposures . However, toxicity of metal‐contaminated suspended particles depends on the primary metal contaminant as well as its solubility .…”

Phosphorus and Metals Leaching from Green Roof Substrates and Aggregates Used in Their Composition

“…Average measured values were 1.79, 0.43, 1.26, and 0.48 mg/kg for S8, S11, S12, and B3, respectively. Recently, the ecotoxicity of nickel is increasingly being considered in the literature [37][38][39] because of its bioavailability, bio-accumulation, as well as teratogenic and carcinogenic effect on mammals.…”