Physiological effects of five different marine natural organic matters (NOMs) and three different metals (Cu, Pb, Zn) on early life stages of the blue mussel (Mytilus galloprovincialis)

Abstract

Metals are present in aquatic environments as a result of natural and anthropogenic inputs, and may induce toxicity to organisms. One of the main factors that influence this toxicity in fresh water is natural organic matter (NOM) but all NOMs are not the same in this regard. In sea water, possible protection by marine NOMs is not well understood. Thus, our study isolated marine NOMs by solid-phase extraction from five different sites and characterized them by excitation-emission fluorescence analysis—one inshore (terrigenous origin), two offshore (autochthonous origin), and two intermediate in composition (indicative of a mixed origin). The physiological effects of these five NOMS alone (at 8 mg/L), of three metals alone (copper, lead and zinc at 6 µg Cu/L, 20 µg Pb/L, and 25 µg Zn/L respectively), and of each metal in combination with each NOM, were evaluated in 48-h exposures of mussel larvae. Endpoints were whole body Ca2++Mg2+-ATPase activity, carbonic anhydrase activity and lipid peroxidation. By themselves, NOMs increased lipid peroxidation, Ca2++Mg2+-ATPase, and/or carbonic anhydrase activities (significant in seven of 15 NOM-endpoint combinations), whereas metals by themselves did not affect the first two endpoints, but Cu and Pb increased carbonic anhydrase activities. In combination, the effects of NOMs predominated, with the metal exerting no additional effect in 33 out of 45 combinations. While NOM effects varied amongst different isolates, there was no clear pattern with respect to optical or chemical properties. When NOMs were treated as a single source by data averaging, NOM had no effect on Ca2++Mg2+-ATPase activity but markedly stimulated carbonic anhydrase activity and lipid peroxidation, and there were no additional effects of any metal. Our results indicate that marine NOMs may have direct effects on this model marine organism, as well as protective effects against metal toxicity, and the quality of marine NOMs may be an important factor in these actions.

Updated species sensitivity distribution evaluations for acute and chronic lead toxicity to saltwater aquatic life

“…In a marine diatom ( Thalassiosira weissflogii ), humic acid did not alter the amount of Pb that was internalized, although humic acid concentrations were positively related with adsorption of Pb to the exterior of the cell wall of the diatom . Nogueira et al observed that enzyme activity in embryonic Mytilus galloprovincialis was altered during 48‐h exposures to several types of natural organic matter but that the addition of metals (including Pb) did not generally alter enzyme activity beyond the effect of organic matter alone. Capodaglio et al measured complexation of Pb in seawater and found that organically complexed Pb accounted for approximately 50% of total Pb.…”

Effects of natural organic matter on the joint toxicity and accumulation of Cu nanoparticles and ZnO nanoparticles in Daphnia magna

“…In particular, in the presence of SR-NOM the accumulation of Cu increased more obviously. NOM was previously shown to reduce metal bioavailability via chelating and sequestering metal cations (Gheorghiu et al, 2010;Al-Reasi et al, 2011;DePalma et al, 2011;Nogueira et al, 2017;Qiao et al, 2019). Nevertheless, it cannot be excluded that metal ions bound with NOM are available accumulation by aquatic organisms (Wang et al, 2016), especially for D. magna which can ingest suspended and sediment particles smaller than the reported size limit of 70 μm (Geller and Müller, 1981;Tervonen et al, 2010;Lee and Ranville, 2012).…”

“…Natural organic matter (NOM) plays an important role in modulating the ecotoxicological effects of metals (Nogueira et al, 2017) and nanoparticles (Wang et al, 2011). Previous studies have shown that the addition of NOM reduced the toxicity of metals such as Cu and Zn to aquatic organisms, due to the complexation of metal ions with NOM and thereby decreasing the bioavailability of the metals (Hyne et al, 2005;Nadella et al, 2009;Clifford and McGeer, 2009).…”

Algal Extracellular Organic Matter Induced Photochemical Oxidation of Mn(II) to Solid Mn Oxide: Role of Mn(III)-EOM Complex and Its Ability to Remove 17α-Ethinylestradiol

“…To simulate the stable pH conditions of natural waters, a 10.0 mM sodium borate buffer solution was used to maintain pH 8.0 in all subsequent experiments. Considering the concentration of DOM in surface water, 36 EOM concentrations ranging from 1.0 to 20.0 mgC/L were used to investigate their influence on the photochemical oxidation of Mn(II).…”