Mineralogy and Metallography Division, Institute of Minerals and Materials Technology, Bhubaneswar 751013, India.
Environ Monit Assess. 2013 Apr;185(4):3503-16. doi: 10.1007/s10661-012-2806-7. Epub 2012 Aug 30.
The chemistry of heavy metals in sediments with respect to bio-availability and chemical reactivity is regulated by pH, texture, and organic matter contents of the sediments and specific binding form and coupled reactivity of the metals within. To focus on the metal distribution (Fe, Mn, Pb, Cd, Zn, Co, Cu, and Cr) and behavior in a fresh water aquifer system along with the ecological toxicity parameters, a four-step sequential extraction method was applied on 18 Eastern Ghats' type sediments from fluorosis-hit Nayagarh district, India. Geo-accumulation index of metals in the sediments indicates that they are practically uncontaminated and/or less contaminated with and Fe, Mn, and Cu; contaminated to moderately contaminated with Pb, Zn, and Cr; and strongly contaminated with Cd. Rather, more than 80 % recovered Cd metal concentration in sediments constitute the labile fractions. Temporal clustering of metal fractions indicates transition metal fraction distribution claiming the sediment pH regulation. Similarly, base metal distribution accounts for organic carbon and soil conductivity due to their greater availability in exchangeable and sulfide fractions. Correlation analysis and factor analysis scores demonstrate lack of inter-relationship between transition group and base metal fractions. High fluoride concentration in ground water is associated with high sodium-bicarbonate-iron affinity with elevated pH values (i.e., >7.0) and high positive factor score with the total iron concentration in ground water.
沉积物中重金属的化学性质（包括生物有效性和化学反应活性）受到 pH 值、质地、有机质含量以及金属在沉积物中的特定结合形态和耦合反应性的影响。为了研究淡水含水层系统中金属的分布（Fe、Mn、Pb、Cd、Zn、Co、Cu 和 Cr）和行为以及生态毒性参数，本研究采用四步连续提取法对来自印度氟中毒高发的纳亚加尔区东高止山脉类型的 18 个沉积物样本进行了分析。沉积物中金属的地质累积指数表明，它们实际上无污染或轻度污染，Fe、Mn 和 Cu 的污染程度较低；Pb、Zn 和 Cr 的污染程度为中度污染；Cd 的污染程度为重度污染。此外，超过 80%回收的 Cd 金属浓度存在于沉积物的可利用部分。金属部分的时间聚类表明，过渡金属部分的分布表明了沉积物 pH 值的调节作用。同样，由于其在可交换和硫化物部分的较高可用性，基础金属的分布与有机碳和土壤电导率有关。相关性分析和因子分析得分表明，过渡金属组和基础金属组之间没有相互关系。地下水高氟浓度与高 pH 值（即>7.0）和高正因子得分有关，因为地下水中的铁与高浓度的碳酸氢钠具有较强的亲和力。
