title: Looking for suitable biomarkers in benthic macroinvertebrates inhabiting coastal areas with low metal contamination: comparison between the bivalve Cerastoderma edule and the Polychaete Diopatra neapolitana.
abstract: Metals accumulated in marine sediments are often a threat to benthic communities. With the recognized importance and wide use of stress biochemical responses as indicators of metal contamination it becomes essential to compare these markers between different species and verify their ubiquity and accuracy. Using wild Diopatra neapolitana and Cerastoderma edule, collected at several areas differing in metal contamination, this study aimed to assess the use of these two macrobenthic species as sentinel organisms and to determine the applicability of currently used biomarkers in benthic species exposed to a range of low metal and As concentrations. Total metal accumulation and intracellular partitioning was analyzed and metal-induced alterations were assessed through the analysis of several biochemical parameters in both organisms, including stress-induced reactive oxygen species (ROS), lipid peroxidation and protein content, the activity of antioxidant enzymes catalase (CAT), superoxide dismutase (SOD) and of glutathione S-transferase (GST). Metal chelation by Metallothioneins (MTs) was also determined. Results revealed that D. neapolitana accumulated higher levels of metals when compared to C. edule, independently of the sediment concentration. Results also showed strong species-specific responses to metals and differences in the ability to sequester metals. Overall, C. edule showed to be more efficient metal chelator and precipitatior than D. neapolitana, which was less tolerant and presented oxidative stress. MTs proved to be a good predictor of metal accumulation in both species, even under low metal exposures. On the other hand, lipid peroxidation was a good indicator of oxidative damage, only observed in D. neapolitana, which was a result of higher metal retention in the soluble fraction.
authors: Departamento de Biologia, Universidade de Aveiro, Aveiro, Portugal.
authors: Rosa
authors: R
authors: Freitas
authors: Elisabeth
authors: E
authors: Costa
authors: Cátia
authors: C
authors: Velez
authors: José
authors: J
authors: Santos
authors: Ana
authors: A
authors: Lima
authors: Cristina
authors: C
authors: Oliveira
authors: Ana
authors: A
authors: Maria Rodrigues
authors: Victor
authors: V
authors: Quintino
authors: Etelvina
authors: E
authors: Figueira
mesh_terms: D000818:Animals; D015415:Biomarkers / Q000378:metabolism; D049873:Cardiidae / Q000187:drug effects / Q000378:metabolism*; D002374:Catalase / Q000378:metabolism; D004784:Environmental Monitoring / Q000379:methods*; D019015:Geologic Sediments / Q000737:chemistry; D005982:Glutathione Transferase / Q000378:metabolism; D015227:Lipid Peroxidation / Q000187:drug effects; D008668:Metallothionein / Q000378:metabolism; D008670:Metals / Q000633:toxicity*; D018384:Oxidative Stress; D011077:Polychaeta / Q000187:drug effects / Q000378:metabolism*; D013482:Superoxide Dismutase / Q000378:metabolism; D014874:Water Pollutants, Chemical / Q000633:toxicity*
chemical_list: D015415:Biomarkers; D008670:Metals; D014874:Water Pollutants, Chemical; D008668:Metallothionein; D002374:Catalase; D013482:Superoxide Dismutase; D005982:Glutathione Transferase