Abstract：
Landfills, especially those poorly managed, can negatively affect the environment and human beings through chemical contamination of soils and waters. This study investigates the soils of a historical municipal solid waste (MSW) landfill situated in the heart of a residential zone in the capital of Slovakia, Bratislava, with an emphasis on metal (loid) contamination and its consequences. Regardless of the depth, many of the soils exhibited high metal (loid) concentrations, mainly Cd, Cu, Pb, Sb, Sn and Zn (up to 24, 2620, 2420, 134, 811 and 6220 mg/kg, respectively), classifying them as extremely contaminated based on the geo-accumulation index (Igeo >5). The stable lead isotopic ratios of the landfill topsoil varied widely (1.1679-1.2074 for 206Pb/207Pb and 2.0573-2.1111 for 208Pb/206Pb) and indicated that Pb contained a natural component and an anthropogenic component, likely municipal solid waste incineration (MSWI) ash and construction waste. Oral bioaccessibility of metal (loid)s in the topsoil was variable with Cd (73.2-106%) and Fe (0.98-2.10%) being the most and least bioaccessible, respectively. The variation of metal (loid) bioaccessibility among the soils could be explained by differences in their geochemical fractionation as shown by positive correlations of bioaccessibility values with the first two fractions of BCR (Community Bureau of Reference) sequential extraction for As, Cd, Mn, Ni, Pb, Sn and Zn. The results of geochemical fractionation coupled with the mineralogical characterisation of topsoil showed that the reservoir of bioaccessible metal (loid)s was calcite and Fe (hydr)oxides. Based on aqua regia metal (loid) concentrations, a non-carcinogenic risk was demonstrated for children (HI = 1.59) but no risk taking into account their bioaccessible concentrations (HI = 0.65). This study emphasises the need for detailed research of the geochemistry of wastes deposited in urban soils to assess the potentially hazardous sources and determine the actual bioaccessibility and human health risks of the accumulated metal (loid)s.
摘要：
垃圾填埋场,尤其是那些管理不善的人，会通过土壤和水域的化学污染对环境和人类产生负面影响。这项研究调查了位于斯洛伐克首都居民区中心的历史城市固体废物（MSW）垃圾填埋场的土壤，布拉迪斯拉发,重点是金属（类）污染及其后果。不管深度,许多土壤表现出很高的金属(类)浓度，主要是Cd,Cu,Pb,Sb,Sn和Zn（最高为24、2620、2420、134、811和6220mg/kg，分别)，根据地质累积指数(Igeo>5)将它们分类为极端污染。垃圾填埋场表土的稳定铅同位素比变化很大（206Pb/207Pb为1.1679-1.2074，208Pb/206Pb为2.0573-2.1111），表明Pb含有天然成分和人为成分，可能是城市固体废物焚烧(MSWI)灰和建筑垃圾。表层土壤中金属（类）的口腔生物可及性是可变的，其中Cd（73.2-106％）和Fe（0.98-2.10％）的生物可及性最大和最小，分别。土壤中金属（类）生物可及性的变化可以通过其地球化学分馏的差异来解释，如生物可及性值与BCR（社区参考局）顺序提取的前两个部分的正相关所示。Cd,Mn,Ni,Pb,Sn和Zn。地球化学分馏的结果表明，表土的矿物学特征表明，生物可利用金属（类）的储层是方解石和Fe（hydr）氧化物。基于王水金属(loid)浓度，已证实儿童存在非致癌风险(HI=1.59),但考虑到其生物可接近浓度(HI=0.65),则无风险.这项研究强调需要对城市土壤中沉积的废物的地球化学进行详细研究，以评估潜在的危险源并确定累积金属（类）的实际生物可及性和人类健康风险。
