Stopford Woodhall, Turner John, Cappellini Danielle, Brock Tom
Duke University Medical Center, Department of Community & Family Medicine, Division of Occupational & Environmental Medicine, Box 3834, Durham, NC 27710, USA.
J Environ Monit. 2003 Aug;5(4):675-80. doi: 10.1039/b302257a.
Testing of metal compounds for solubility in artificial fluids has been used for many years to assist determining human health risk from exposure to specific compounds of concern. In lieu of obtaining bioavailability data from samples of urine, blood, or other tissues, these studies measured solubility of compounds in various artificial fluids as a surrogate for bioavailability. In this context, the measurement of metal "bioaccessibility" can be used as an in vitro substitute for measuring metal bioavailability. Bioaccessibility can be defined as a value representing the availability of metal for absorption when dissolved in in vitro surrogates of body fluids or juices. The aim of this study was to measure and compare the bioaccessibility of selected cobalt compounds in artificial human tissue fluids and human serum. A second aim was to initiate studies to experimentally validate an in vitro methodology that would provide a conservative estimate of cobalt bioavailability in the assessment of dose from human exposure to various species of cobalt compounds. This study evaluated the bioaccessibility of cobalt(II) from 11 selected cobalt compounds and an alloy in 2 physical forms in 5 surrogate human tissue fluids and human serum. Four (4) separate extraction times were used up to 72 hours. The effect of variables such as pH, dissolution time, and mass-ion effect on cobalt bioaccessibility were assessed as well. We found that the species of cobalt compound as well as the physico-chemical properties of the surrogate fluids, especially pH, had a major impact on cobalt solubility. Cobalt salts such as cobalt(II) sulfate heptahydrate were highly soluble, whereas cobalt alloys used in medical implants and cobalt aluminate spinels used as pigments, showed minimal dissolution over the period of the assay.
多年来，一直通过测试金属化合物在人工体液中的溶解度来辅助确定人体接触特定关注化合物后的健康风险。由于无法从尿液、血液或其他组织样本中获取生物利用度数据，这些研究将化合物在各种人工体液中的溶解度作为生物利用度的替代指标进行测量。在此背景下，金属“生物可及性”的测量可作为测量金属生物利用度的体外替代方法。生物可及性可定义为一个值，代表金属溶解于体外模拟体液或汁液时可供吸收的程度。本研究的目的是测量并比较选定钴化合物在人工人体组织液和人血清中的生物可及性。第二个目的是启动实验研究，以验证一种体外方法，该方法能在评估人体接触各种钴化合物剂量时对钴的生物利用度提供保守估计。本研究评估了11种选定钴化合物和一种合金中两种物理形态的钴（II）在5种模拟人体组织液和人血清中的生物可及性。使用了4个不同的提取时间，最长达72小时。还评估了pH值、溶解时间和质量离子效应等变量对钴生物可及性的影响。我们发现，钴化合物的种类以及模拟液的物理化学性质，尤其是pH值，对钴的溶解度有重大影响。七水合硫酸钴等钴盐高度可溶，而用于医疗植入物的钴合金和用作颜料的钴铝酸盐尖晶石在测定期间的溶解极少。
