State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, 73, East Beijing Road, Nanjing, China,
Environ Sci Pollut Res Int. 2014 Jun;21(12):7285-95. doi: 10.1007/s11356-014-2639-8. Epub 2014 Feb 26.
Total and extractable concentrations of Cu, Pb, and Zn were determined in surface sediments of west Chaohu Lake (China) by HCl-HNO3-HF-HClO4 digestion and an optimized BCR sequential extraction procedure, respectively. The metal pollution was evaluated by the enrichment factor approach, and the potential eco-risk was evaluated by the sediment quality guideline (SQG) and risk assessment code (RAC) assessments. The results indicated that both total and extractable metal concentrations were highly variable and were affected by sediment properties, even though the sediments were predominantly composed of <63-μm particles (>89%). Enrichment factors of the metals based on the total and extractable concentrations all showed higher values in the northern lake area and decreasing values towards the south. This distribution indicated an input of anthropogenic metals via the Nanfei River. Anthropogenic Cu, Pb, and Zn in surface sediments showed comparable values for each metal based on the total and extractable concentrations, suggesting that anthropogenic Cu, Pb, and Zn resided predominantly in the extractable fractions. Sediment Cu had low eco-risk, and Pb and Zn had medium eco-risk by the SQG assessment, whereas the eco-risk rankings of Cu, Pb, and Zn were medium, low, and low-high, respectively, by the RAC assessment. Referencing to the labile (dilute acid soluble) metal concentrations, we deduced that the eco-risk of Cu may be largely overestimated by the RAC assessment, and the eco-risk of Pb may be largely overestimated by the SQG assessment. Overall, sediments Cu and Pb may pose low eco-risk, and Zn may pose low-high eco-risk.
采用 HCl-HNO3-HF-HClO4 消解和优化的 BCR 连续提取程序，分别测定了中国西部巢湖表层沉积物中 Cu、Pb 和 Zn 的总量和可提取浓度。采用富集因子法评价了金属污染，采用沉积物质量准则（SQG）和风险评估代码（RAC）评价了潜在生态风险。结果表明，尽管沉积物主要由<63-μm 颗粒（>89%）组成，但总金属和可提取金属浓度均高度可变，受沉积物性质的影响。金属的富集因子基于总浓度和可提取浓度都显示出在北部湖区的较高值，并且朝着南部逐渐降低。这种分布表明通过南淝河输入了人为金属。根据总浓度和可提取浓度，表层沉积物中的人为 Cu、Pb 和 Zn 具有相似的各金属值，表明人为 Cu、Pb 和 Zn 主要存在于可提取部分。根据 SQG 评估，沉积物 Cu 的生态风险较低，Pb 和 Zn 的生态风险为中等，而根据 RAC 评估，Cu、Pb 和 Zn 的生态风险等级分别为中等、低和低-高。参考可利用（稀酸可溶）金属浓度，我们推断 RAC 评估可能会大大高估 Cu 的生态风险，而 SQG 评估可能会大大高估 Pb 的生态风险。总体而言，沉积物 Cu 和 Pb 可能具有低生态风险，而 Zn 可能具有低-高生态风险。
