The University of Queensland, National Research Centre for Environmental Toxicology, Brisbane, QLD 4108, Australia; Cooperative Research Centre for Contamination Assessment and Remediation of the Environment, The University of Newcastle, Callaghan, NSW 2308, Australia.
Cooperative Research Centre for Contamination Assessment and Remediation of the Environment, The University of Newcastle, Callaghan, NSW 2308, Australia; The University of Newcastle, Global Centre for Environmental Remediation, Callaghan, NSW 2308, Australia.
Chemosphere. 2016 Jul;154:343-349. doi: 10.1016/j.chemosphere.2016.03.133. Epub 2016 Apr 7.
The bioaccessibility of lead (Pb) in contaminated soils has been extensively studied, including the influence of soil properties on Pb bioaccessibility. However, little is known about the effects of other metals/metalloid, such as arsenic (As), cadmium (Cd) on the bioaccessibility of Pb, i.e. whether As or Cd could increase or decrease the solubility of Pb in human gastrointestinal tract when Pb-contaminated soil and As-contaminated (or Cd-contaminated) soil are ingested simultaneously. Furthermore, it is far from clear that if soil property could make a difference to these effects. In this study, seven types of soils were collected in Australia and spiked with As, Cd or Pb. Gastric bioaccessibility of Pb ranged from 44 ± 0.9% to 100 ± 6.7% whilst intestinal bioaccessibility dropped to 1 ± 0.2% to 36 ± 1.7%. Statistical analysis shows total Pb in soil was the most significant controller for bioaccessible Pb. Effects of As and Cd on the bioaccessibility of Pb in simulated human digestive system were studied by mixing As-spiked soil (or Cd-spiked soil) with Pb-spiked soil of the same type during bioaccessibility test. Results reveal that neither As nor Cd had impact on Pb bioaccessibility, which indicates when As, Cd and Pb aged in soils separately, they may behave independently in the bioaccessibility measuring system. This finding can be part of evidence to assume additive effect when it comes to estimate the bioaccessibility of mixtures of independently-aged As and Pb (or Cd and Pb) in soils.
已广泛研究了污染土壤中铅（Pb）的生物可给性，包括土壤特性对 Pb 生物可给性的影响。然而，人们对其他金属/类金属（如砷（As）、镉（Cd））对 Pb 生物可给性的影响知之甚少，即在同时摄入含 Pb 污染土壤和含 As 污染（或含 Cd 污染）土壤时，As 或 Cd 是否会增加或降低 Pb 在人体胃肠道中的溶解度。此外，土壤性质是否会对这些影响产生影响，目前还远不清楚。在这项研究中，从澳大利亚收集了七种类型的土壤，并对其进行了 As、Cd 或 Pb 的掺杂。Pb 的胃生物可给性范围为 44 ± 0.9%至 100 ± 6.7%，而肠道生物可给性则降至 1 ± 0.2%至 36 ± 1.7%。统计分析表明，土壤中总 Pb 是控制生物可给性 Pb 的最主要因素。通过在生物可给性测试中混合含 As 污染的土壤（或含 Cd 污染的土壤）和相同类型的含 Pb 污染的土壤，研究了 As 和 Cd 对模拟人体消化系统中 Pb 生物可给性的影响。结果表明，As 和 Cd 对 Pb 生物可给性均无影响，这表明当 As、Cd 和 Pb 在土壤中分别老化时，它们在生物可给性测量系统中可能表现出独立性。这一发现可以作为证据的一部分，即在估计土壤中独立老化的 As 和 Pb（或 Cd 和 Pb）混合物的生物可给性时，可以假设其具有相加效应。
