The influence of body size, condition index and tidal exposure on the variability in metal bioaccumulation in <i>Mytilus edulis</i>

Mussels are commonly used to monitor metal pollution despite high inter-individual variability in tissue concentrations. In this study, influences of body size, condition index and tidal height on concentrations of As, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb and Zn were investigated. Body weight was inversely related to metal concentrations and for Cd, Mn, Pb and Zn the regression was affected by tidal height. Except for As, Fe and Mn metal concentrations were inversely related to physiological status though no differences between essential and non-essential metals were obvious. After correcting for body size, tidal height was related positively to As, Cd and Zn, negatively related to Cu, Fe and Mn while Co, Cr, Ni and Pb were independent of tidal height. The study recommends stringent measures during sampling for biomonitoring or metal concentrations at each location must be normalized to a common body size, CI and tidal height

Copper uptake by the marine mussel, <i>Mytilus edulis</i> in the presence of fulvic acids

Copper uptake and accumulation by the marine mussel Mytilus edulis were studied at different Cu concentrations in chemically defined artificial seawater in the presence and absence of fulvic acids. Both short-term uptake of Cu by excised mussel gills and Cu accumulation in whole mussels after 24?h of exposure decreased in the presence of fulvic acids compared with their absence at similar dissolved Cu concentrations. Calculations of Cu speciation based on previous measurements of labile Cu by anodic stripping voltammetry demonstrated that Cu uptake and accumulation depended on the concentration of labile Cu, in agreement with the free ion activity model. No evidence of a significant uptake of Cu–fulvic acid complexes was observed

Pb uptake by the mussel Mytilus. Interactions with dissolved organic matter

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Pb uptake by the mussel Mytilus. Interactions with dissolved organic matter

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Pb uptake by the marine mussel <i>Mytilus</i> sp. Interactions with dissolved organic matter

It is well known that dissolved organic matter binds metal ions and buffers them in natural waters. Although it is believed that a decrease in metal ion concentration should lead to a decrease in metal bioavailability, previous work has shown that Pb uptake by Mytilus edulis gills is greatly enhanced in the presence of humic acids. In the present work, the effect of more soluble organic matter (fulvic acids and DOM extracted from river) on Pb uptake by mussels and their gills is studied. Pb complexation by these organic substances was measured by anodic stripping voltammetry (ASV) and it is proven that Pb uptake by mussel gills in the presence of fulvic acids can be successfully predicted according to ASV-labile Pb concentrations. However, Pb uptake by whole mussels in the presence of river DOM is slightly higher than predicted on the basis of ASV measurements. The possible reasons leading to different effects of DOM on Pb uptake by mussels are discussed according to physicochemical properties of DOM

Pb uptake by the mussel Mytilus. Interactions with dissolved organic matter

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Habitat type-based bioaccumulation and risk assessment of metal and As contamination in earthworms, beetles and woodlice

The present study investigated the contribution of environmental factors to the accumulation of As, Cd, Cu, Pb and Zn in earthworms, beetles and woodlice, and framed within an exposure assessment of the European hedgehog. Soil and invertebrate samples were collected in three distinct habitat types. Results showed habitat-specific differences in soil and invertebrate metal concentrations and bioaccumulation factors when normalized to soil metal concentration. Further multiple regression analysis showed residual variability (habitat differences) in bioaccumulation that could not be fully explained by differences in soil metal contamination, pH or organic carbon (OC). Therefore, the study demonstrated that in bioaccumulation studies involving terrestrial invertebrates or in risk assessment of metals, it is not sufficient to differentiate habitat types on general soil characteristics such as pH and/or OC alone. Furthermore, simple generic soil risk assessments for Cd and Cu showed that risk characterization was more accurate when performed in a habitat-specific way. Our study provided essential insights into habitat-specific accumulation patterns with respect to factors influencing metal bioaccumulation, BAFs, and site-specific risk assessmen