Essential metal contents in indigenous gammarids related to exposure levels at the river basin scale: Metal-dependent models of bioaccumulation and geochemical correlations

• Published in: The Science of the total environment Vol. 466-467; pp. 100 - 108
• Main Authors: Lebrun, Jérémie D., Uher, Emmanuelle, Tusseau-Vuillemin, Marie-Hélène, Gourlay-Francé, Catherine
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.01.2014; Elsevier
• Subjects: Amphipoda - drug effects; Animals; Biomonitor; Copper; Copper - toxicity; Dose-Response Relationship, Drug; Environmental Exposure; Environmental Monitoring - methods; Environmental Sciences; France; Gammarus pulex; Manganese; Manganese - toxicity; Mass Spectrometry; Metal bioavailability; Rivers - chemistry; Zinc; Zinc - toxicity; France; Metal bioavailability; Gammarus pulex; Biomonitor; Copper; Zinc; Manganese; METAL BIOAVAILABILITY; GAMMARUS PULEX
• ISSN: 0048-9697; 1879-1026
• DOI: 10.1016/j.scitotenv.2013.07.003

Biomonitoring, assumed to be an integrative measurement of the chemical exposure of aquatic organisms, is not straightforward for essential metals because they can be actively regulated by animals. Although increasing bioaccumulation with exposure levels is a crucial endpoint for the development of biomonitors, it is rarely verified in real environments, where the metal concentrations are rather low and vary little. This study was designed at the scale of a river basin to assess the ability of Gammarus pulex indigenous populations to accumulate Cu, Zn and Mn in realistic exposure conditions. During two annual campaigns, water and gammarids were collected at various sites contrasted in terms of physicochemistry and contamination. The results show significant relationships between metal concentrations in animals and in freshwaters established by conceptual models of bioaccumulation, but with patterns specific to each metal (base level, internal regulation and maximal accumulation). In particular, a saturation process of Cu accumulation occurs at environmental exposure levels, unlike Mn and Zn. Statistical analyses performed from field data show that Cu and Zn bioaccumulations may be influenced by a complex combination of geochemical variables, unlike Mn. We conclude that G. pulex is a useful candidate to monitor metal bioavailability in freshwaters due to its responsiveness to low exposures of surrounding environments. Nevertheless, a reliable quantification of bioavailability of essential metals requires characterizing some geochemical effects on metal bioaccumulation. •Cu, Zn and Mn accumulations by gammarids are assessed in realistic exposure conditions.•Indigenous populations were sampled in many contrasted freshwaters at the basin scale.•Metal contents in gammarids increase with freshwater contamination levels.•Bioaccumulation is modeled according to patterns specific to each essential metal.•Statistical analyses report geochemical correlations to Cu and Zn bioaccumulations.