Guangdong Provincial Key Laboratory of Soil and Groundwater Pollution Control, School of Environmental Science and Engineering, Southern University of Science and Technology, Shenzhen, 518055, China; State Environmental Protection Key Laboratory of Integrated Surface Water-Groundwater Pollution Control, School of Environmental Science and Engineering, Southern University of Science and Technology, Shenzhen, 518055, China.
Beijing Geotechnical and Investigation Engineering Institute, Beijing, 100086, China.
Environ Pollut. 2020 May;260:113986. doi: 10.1016/j.envpol.2020.113986. Epub 2020 Jan 21.
Heavy metal contamination in the Bohai Sea (China) has been the focus of many studies, but most of them only focused on local pollution levels and thus lacked high spatial resolution for the whole sea. In this study, heavy metals (i.e., As, Cr, Cu, Cd, Pb, Zn, and Fe) in surface sediments were analyzed to assess the spatio-temporal pollution conditions of the Bohai Sea, an important coastal environment consisting of Bohai Bay, Laizhou Bay, and Liaodong Bay. The results indicated that the heavy metal concentration in the sediments was in the range of 6.43-32.18 mg/kg for As, 14.90-58.07 mg/kg for Cr, 3.90-27.19 mg/kg for Cu, 0.04-0.27 mg/kg for Cd, 11.09-30.95 mg/kg for Pb, 18.76-65.58 mg/kg for Zn, and 0.78%-2.55% for Fe. The distribution of heavy metals revealed that the concentrations were relatively low in Laizhou Bay, very high in the northwest coastal region of the Bohai Sea, and decreased from near-shore to off-shore areas. Moreover, both the enrichment factor and geo-accumulation index demonstrated that there was no contamination to be found for Cr, Cu, Zn in the region and a slight to moderate pollution of As, Cd, and Pb. Cd and As presented considerable potential ecological risk as a result of their high toxicity. The potential ecological risk index (RI) suggested that a third of the areas (northwest coastal area of the Bohai Sea) has moderate ecological risk. The risk area was generally decreased as offshore distance increased, which suggested that the contamination and risk of heavy metals are influenced by anthropogenic activities.
渤海（中国）海域的重金属污染一直是许多研究的焦点，但大多数研究仅关注局部污染水平，因此缺乏对整个海域的高空间分辨率。本研究分析了表层沉积物中的重金属（即 As、Cr、Cu、Cd、Pb、Zn 和 Fe），以评估渤海这一重要沿海环境（由渤海湾、莱州湾和辽东湾组成）的时空污染状况。结果表明，沉积物中重金属的浓度范围为 As 6.43-32.18mg/kg、Cr 14.90-58.07mg/kg、Cu 3.90-27.19mg/kg、Cd 0.04-0.27mg/kg、Pb 11.09-30.95mg/kg、Zn 18.76-65.58mg/kg 和 Fe 0.78%-2.55%。重金属的分布表明，莱州湾的浓度相对较低，渤海西北部沿海地区的浓度非常高，且从近岸向远岸逐渐降低。此外，富集因子和地积累指数均表明，该地区的 Cr、Cu 和 Zn 无污染，As、Cd 和 Pb 有轻微至中度污染。由于 Cd 和 As 毒性较高，它们具有相当大的潜在生态风险。潜在生态风险指数（RI）表明，三分之一的区域（渤海西北部沿海地区）具有中等生态风险。随着离岸距离的增加，风险区域通常会减少，这表明重金属的污染和风险受到人为活动的影响。
