Mufalo Walubita, Tangviroon Pawit, Igarashi Toshifumi, Ito Mayumi, Sato Tsutomu, Chirwa Meki, Nyambe Imasiku, Nakata Hokuto, Nakayama Shouta, Ishizuka Mayumi
Division of Sustainable Resources Engineering, Graduate School of Engineering, Hokkaido University, Sapporo 060-8628, Japan.
Division of Sustainable Resources Engineering, Faculty of Engineering, Hokkaido University, Sapporo 060-8628, Japan.
Toxics. 2021 Oct 4;9(10):248. doi: 10.3390/toxics9100248.
Zambia's Kabwe mine wastes (KMWs) are responsible for contaminating the surrounding soil and dust in the Kabwe district. Unfortunately, these wastes arise from the historical mining activities of lead (Pb) and Zinc (Zn), which lacked adequate waste management strategies. As a result, potentially toxic elements (PTEs) (Pb and Zn) spread across the Kabwe district. To assess the soil pollution derived from previous mining activities, we studied topsoil samples ( = 8) from the school playground soils (SPs). In this study, the degree of contamination, geochemical partitioning, and leachability, coupled with the release and retention of Pb and Zn, were studied. The SPs were classified as extremely enriched (EF > 40) and contaminated with Pb (I > 5). On average, Pb (up to 89%) and Zn (up to 69%) were bound with exchangeable, weak acid-soluble, reducible and oxidizable phases, which are considered as 'geochemically mobile' phases in the environment. The leachates from the soils ( = 5) exceeded the Zambian standard (ZS: 190:2010) for Pb in potable drinking water (Pb < 0.01 mg/L). Furthermore, the spatial distribution of Pb and Zn showed a significant reduction in contents of Pb and Zn with the distance from the mine area.
赞比亚的卡布韦矿废弃物（KMWs）致使卡布韦地区周边的土壤和尘土受到污染。不幸的是，这些废弃物源自过去铅（Pb）和锌（Zn）的开采活动，当时缺乏适当的废弃物管理策略。结果，潜在有毒元素（PTEs）（铅和锌）在卡布韦地区扩散开来。为评估先前采矿活动造成的土壤污染，我们研究了学校操场土壤（SPs）的表层土样本（n = 8）。在本研究中，对污染程度、地球化学分配和可浸出性，以及铅和锌的释放与保留情况进行了研究。学校操场土壤被归类为极度富集（富集因子> 40）且受到铅污染（污染指数> 5）。平均而言，铅（高达89%）和锌（高达69%）与可交换相、弱酸可溶相、可还原相和可氧化相结合，这些在环境中被视为“地球化学可移动”相。土壤渗滤液（n = 5）中铅的含量超过了赞比亚饮用水标准（ZS: 190:2010）（铅< 0.01毫克/升）。此外，铅和锌的空间分布显示，随着与矿区距离的增加，铅和锌的含量显著降低。
