Elemental Status in Sediment and American Oyster Collected from Savannah Marsh/Estuarine Ecosystem: A Preliminary Assessment

Abstract

Sediment and American oyster (Crassostrea virginica) collected from nine selected marsh/estuarine ecosystems in Savannah, Georgia were analyzed for elements such as Al, As, B, Cd, Cr, Cu, Fe, Hg, Mn, Mo, Ni, Pb, Si, and Zn. Sediments were extracted by ammonium acetate (NH(4)OAc), Mehlich-3 (M-3), and water procedures, whereas an acid digestion procedure was adopted for oyster tissue. Concentrations of elements were higher in M-3 extractions followed by NH(4)OAc and water extraction procedures. Calcium and Mg was greater in sediments by any of the extractions, whereas other elements differed depending upon the extraction procedures. There were no significant spatial variations (p < 0.05) of any of elements analyzed except Mn, in NH(4)OAc/water extraction procedure and Fe and Al by water extraction procedure. Contamination of Al, B, Cd, Cr, Cu, Fe, Mn, Mo, Ni, Pb, Si, and Zn in oyster tissue ranged from 399 to 1460, 231 to 254, <1.5 to 2.9, <1.5 to 8.0, 67 to 121, 232 to 1357, 17 to 54, <0.5 to 0.64, <1.5 to 2.5, <1.5 to 4.0, 241 to 381, and 978 to 2428 microg/g dry weight (dw), respectively. Greatly elevated concentrations of elements such as P, Ca, Mg, K, and S were noticed in oyster tissue. The concentration range of Hg and As in sediment was 1.2-1.9 and 11-55 microg/g dw, respectively. The concentration range of Hg and As in oyster tissue was 130-908 and 200-912 ng/g dw, respectively. With the exception of As and Hg, other elements are several orders of magnitude greater in oyster tissue. There is no significant (p < 0.05) contamination variation in target analyses between the nine selected sites. Concentrations of heavy metals in sediment and oyster were either comparable or lower than those of other countries. Greater biota-sediment accumulation factor was noticed for P and Zn. Concentrations of Hg and P in oyster tissue were higher than the threshold limit for human consumption. Overall, the baseline data can be used for regular ecological monitoring, considering the domestic and industrial growth around this important marsh/estuarine ecosystem.

Geochemical distribution of heavy metals in sediments from sewage fed fish ponds from Kolkata Wetlands, India

“…The order of abundance of metals was observed as: Fe4Al4Mn4Zn4Cu4Pb4Cr4Ni, which follows a natural progressive concentration of heavy metals in sediments (Turekian and Wedepohl, 1961). This same ranking was also reported by other workers ( (Karupadam et al, 2003;Sajwan et al, 2008;Senthil Kumar et al, 2007;Kumar et al, 2010) in different aquatic ecosystems. The concentration of major heavy metals, Fe (32747 mg g À 1 ) and Al (23371 mg g À 1 ) were the most dominant followed by Mn (327), Zn (169), Cu (54), Pb (38) Cr (29), and Ni (25) mg g À 1 .…”

Use of Solen brevis as a Biomonitor for Cd, Pb and Zn on the Intertidal Zones of Bushehr–Persian Gulf, Iran

“…Moreover, the ST/Sh ratio for Zn was considerably greater than unity (i.e., 5.5-6.0). The elevated level of Zn in the soft tissue of S. brevis compared to Cd and Pb might be due to the major role played by Zn in metabolism (Kamaruzzaman et al 2010), its binding with metallothioneins (Sajwan et al 2008), and a possible protective role against the toxicity of other metals. Joksimovic et al (2011) suggested that Zn appears to have a protective effect against the toxicities of both Cd and Pb in the soft tissue.…”

“…The existence of excess heavy metals in aquatic ecosystems can affect sediments and organisms. Sediments act as an important sink of heavy metals (Sajwan et al 2008;Kesavan et al 2010). In addition, sediments are a potential non-point source of heavy metals which may directly influence overlying waters (Houngyi et al 2009).…”

Concentration of Mercury in Cockles (Anadara granosa and A. antiquata) Harvested from Estuaries of Western Lombok, Indonesia, and Potential Risks to Human Health

“…This study contributes a second dataset evaluating mercury contamination in a WLI aquatic food consumed by people. Besides having an important economic value cockles like other bivalves have already been proposed as biomonitoring organisms to assess metals pollution due to their capability to accumulate metals within their tissues (Sajwan et al 2008). Brock and Wolowicz (1994) reported that the biochemical composition of cockle Cerastoderma glaucum tissue was different for populations from Northern Europe, French west coast, and the Western Mediterranean.…”