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  • Artigo IPEN-doc 20088
    Enrichment diagram (ED)
    2014 - RIBEIRO, ANDREZA P.; FIGUEIREDO, ANA M.G.; SANTOS, JOSE O. dos; DANTAS, ELIZABETH S.K.; COTRIM, MARYCEL E.B.; FERREIRA, PAULO A. de L.; FRANÇA, ELVIS J. de; GRAUDENZ, GUSTAVO S.; MAHIQUES, MICHEL M. de; FIGUEIRA, RUBENS C.L.; WASSERMAN, JULIO C. de F.A.
    Purpose – The purpose of this paper is to validate and apply enrichment diagrams (EDs) to determine metal and as enrichment and contamination in the sediments of Sepetiba Bay. Design/methodology/approach – Through inducted coupled plasma – optical emission spectrophotometry, total element (As, Cd, Cu, Ni, Pb and Zn) concentrations were assessed for the construction of EDs and comparison with enrichment factors (EFs) in 65 samples collected in Sepetiba Bay. Findings – Based on the EDs, it was observed that the sediments around the urban area of Sepetiba and Itaguaı´Harbor were contaminated with Cd, Cu, Ni, Pb and Zn. These contaminants were expected due to the urban and industrial discharges into the bay and the activities at Itaguaı´Harbor. Originality/value – The ED was successful regarding its ability to evaluate inorganic contamination in Sepetiba Bay. In addition, this method was able to define a proper background sample for calculating EFs.
  • Artigo IPEN-doc 19042
    Combined SEM/AVS and attenuation of concentration models for the assessment of biovailability and modified of metals in sediments of Septiba Bay (SE Brazil)
    2013 - RIBEIRO, ANDREZA P.; FIGUEIREDO, ANA M.G.; SANTOS, JOSE O. dos; DANTAS, ELIZABETH; COTRIM, MARYCEL E.B.; FIGUEIRA, RUBENS C.L.; SILVA FILHO, EMMANOEL V.; WASSERMAN, JULIO C.
    This study proposes a new methodology to study contamination, bioavailability and mobility of metals (Cd, Cu, Ni, Pb, and Zn) using chemical and geostatistics approaches in marine sediments of Sepetiba Bay (SE Brazil). The chemical model of SEM (simultaneously extracted metals)/AVS (acid volatile sulfides) ratio uses a technique of cold acid extraction of metals to evaluate their bioavailability, and the geostatistical model of attenuation of concentrations estimates the mobility of metals. By coupling the two it was observed that Sepetiba Port, the urban area of Sepetiba and the riverine discharges may constitute potential sources of metals to Sepetiba Bay. The metals are concentrated in the NE area of the bay, where they tend to have their lowest mobility, as shown by the attenuation model, and are not bioavailable, as they tend to associate with sulfide and organic matter originated in the mangrove forests of nearby Guaratiba area.