An Integrated Approach to the Assessment of Pollutant Delivery Chronologies to Impacted Areas: Hg in the Augusta Bay (Italy)

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• 作者：Luca Giorgio Bellucci ; Silvia Giuliani ; Stefania Romano ; Sonia Albertazzi ; Cristian Mugnai ; Mauro Frignani
• 刊名：Environmental Science & Technology (ES&T)
• 出版年：2012
• 出版时间：February 21, 2012
• 年：2012
• 卷：46
• 期：4
• 页码：2040-2046
• 全文大小：458K
• 年卷期：v.46,no.4(February 21, 2012)
• ISSN：1520-5851

文摘

Assessing pollution levels and trends in heavily impacted environments is important but hardly achievable due to the difficulty of recovering suitable undisturbed sediment records. An integrated approach is here presented to solve this kind of problem. It was adopted in the Augusta Bay (Italy) for the study of Hg historical inputs and present trends. Archive information on dredging and mud disposal, together with bathymetry and high-resolution seismic profiles, were used to identify suitable sampling sites. Undisturbed sediment cores were collected in the port and bay. Sediments were analyzed for depth distributions of radiotracers (²¹⁰Pb and ¹³⁷Cs), Hg, and main sediment parameters (magnetic susceptibility, grain size, dry bulk density, mineralogy, and organic carbon and nitrogen contents). Hexachlorobenzene (HCB) was also analyzed as an additional time tracer, since its production history in the area was well-known. Results show that peak Hg contamination (up to 575 mg路kg^鈥?) was reached in the 1970s. Technological improvements and waste treatment in the following years determined a consistent decrease, but high concentrations still affect surficial sediments (0.25鈥?2 mg路kg^鈥?). Hg鈥揌CB correlation suggests that this situation is likely the effect of resuspension and redistribution of deep sediments by dredging and naval traffic.