Metal Water-Sediment Interactions and Impacts on an Urban Ecosystem

Abstract

The EU Water Framework Directive (WFD) requirement that all surface water bodies achieve good ecological status is still a goal for many regulatory authorities in England and Wales. This paper describes field and laboratory studies designed to identify metal contaminant loadings and their distributions within water bodies located in the Lower Lee catchment (London, UK). Water and sediment samples have been collected from increasingly urbanised sites on the River Lee and its main tributaries over a two-year period with samples analysed for total concentrations of cadmium, copper, lead, mercury, nickel, tin, and zinc. Complimentary batch tests indicate a positive relationship between aqueous metal concentrations and the batch test-derived sediment metal release data, particularly during wet weather events. Field data indicate a dynamic relationship between water and sediment concentrations with both being capable of exceeding relevant environmental quality standards/sediment quality guidelines at all sites. Mean sediment metal concentrations across all sites were found to be highest for Cu (141.1 ± 111.0 µg g−1), Pb (175.7 ± 83.0 µg g−1), and Zn (499.9 ± 264.7 µg g−1) with Zn demonstrating elevated mean water concentrations (17.2 ± 13.8 µg L−1) followed by Ni (15.6 ± 11.4 µg L−1) and Cu (11.1 ± 17.8 µg L−1).

Determination and comparison of selected heavy metal concentrations in seawater and sediment samples in the coastal area of Suva, Fiji

“…The collected sediment samples were dried to constant weight at 105 °C for 24 h and ground to a uniform particle size. The sediment samples were then sieved through a 63 μm plastic sieve to obtain 63 μm fraction for the metal analysis (Lundy et al, 2017). For digestion of sediment samples, 1 g of each sample was weighed into a beaker and was digested with 20 mL of aqua regia (HCl:HNO 3 ; 3:1) on a hot plate at 90 °C until the volume reduced to about 2-3 mL.…”

“…The blanks were prepared using DDW in the same way as the water and sediment samples were treated. The digests were analysed by flame atomic absorption spectrophotometer (FAAS) using air-acetylene flame (Lundy et al, 2017;Öztürk et al, 2009) at the wavelengths 228.80 nm, 324.75 nm, 232.60, 283.31 and 213.86 for Cd, Cu, Ni, Pb and Zn, respectively.…”

Assessing the Current Status and Proposing Solutions for Heavy Metal Management in the Saigon River Basin Sediments

“…Hàm lượng tổng Cr phát hiện trong trầm tích lưu vực sông Sài Gòn vào hai mùa mưa và khô thấp hơn so với một số sông ở Bangladesh (112-2471 mg/kg) [24] và cao hơn sông Zambezi (3-24 mg/kg), sông Luangwa (14-39 mg/kg), sông Kafue (8-38 mg/kg) [25]. Đối với hàm lượng Cu trong trầm tích lưu vực sông Sài Gòn cao hơn trầm tích Dumai (1,61-13,84 mg/kg) [26], hạ lưu sông Lee (32,6-161 mg/kg) [27]. Đáng chú ý là hàm lượng Cu phát hiện tại sông Sài Gòn vào mùa mưa cao hơn so với Bagladesh (65-405 mg/kg) [24], sông Cauvery (0,5-68,7 mg/kg) [28] nhưng thấp hơn vào mùa khô.…”

Spatial and vertical distribution analysis of heavy metals in urban retention tanks sediments: a case study of Strzyza Stream

“…The share of Cd in different fractions is as follows: most Cd was related to the fraction of iron-magnesium oxides alternating with the exchangeable fraction [ Cd related to the fraction of organic matter [ Cd linked with the residual fraction. The first two fractions can undergo chemical changes at the sediment-water interface and are susceptible to remobilization in water (Lundy et al 2017). Water pH and elevated chloride concentrations tend to enhance chloride complex formation, which decreases the adsorption of Cd in the sediments, thereby increasing Cd mobility (Islam et al 2015).…”