Food, Nutrition, and Health, Faculty of Land & Food Systems. 2205 East Mall, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada.
School of Food and Biological Engineering, Jiangsu University, Zhenjiang, Jiangsu, 212013, P.R. China.
Sci Rep. 2020 Jun 1;10(1):8823. doi: 10.1038/s41598-020-65449-4.
Commercial mineral clays that claim to have healing properties are also known to contain trace amounts of heavy metals, albeit the risk of consuming many of them is not entirely known. The primary objective of this study was to evaluate the in vitro bioaccessibility and bioavailability of Arsenic (As), Cadmium (Cd) and Lead (Pb) in mineral clay samples collected from the Sierra Mountains (USA) using the Unified Bioaccessibility Research Group of Europe (UBM) method and the Caco-2 permeability assay, respectively. After UMB-gastric (UBM-G) digestion, As and Pb bioaccessibility were lower compared to Cd and decreased further in the UMB-gastrointestinal (UBM-GI) assay. Bioavailability estimates using the Caco-2 cell showed very low to non-detectable permeability for all 3 heavy metals. Thus, while initial heavy metal ranged from 3.8-17 ppm, 0.024-0.061ppm, and 5.8-20 ppm for As, Cd, and Pb, respectively, the bioavailability for these metals was reduced to very low levels that followed: non-detectable values of As, <0.007ppm of Cd, and <0.1ppm of Pb. Using UBM-digestion to mimic bioaccessibility, followed by Caco-2 cell bioavailability enabled us to conclude that in vitro assessment of heavy metal exposure associated with mineral clay-based natural health products does not pose a potential hazard to consumers.
商业用矿物黏土声称具有治疗功效，也被发现含有痕量重金属，尽管人们对食用许多此类物质的风险还不完全了解。本研究的主要目的是使用欧洲统一生物可及性研究组（UBM）方法和 Caco-2 通透性测定法，分别评估从美国塞拉山脉采集的矿物黏土样品中砷（As）、镉（Cd）和铅（Pb）的体外生物可给性和生物利用度。经过 UBM-胃（UBM-G）消化后，As 和 Pb 的生物可给性低于 Cd，在 UBM-胃肠道（UBM-GI）测定中进一步降低。使用 Caco-2 细胞进行生物利用度估算显示，所有 3 种重金属的通透性均非常低或无法检测到。因此，虽然初始重金属含量范围分别为 3.8-17ppm、0.024-0.061ppm 和 5.8-20ppm，但 As、Cd 和 Pb 的生物利用度降低至非常低的水平，具体如下：As 未检出，Cd<0.007ppm，Pb<0.1ppm。使用 UBM 消化模拟生物可给性，然后通过 Caco-2 细胞生物利用度，我们可以得出结论，即体外评估与矿物黏土类天然保健品相关的重金属暴露不会对消费者构成潜在危害。
