a U.S. Environmental Protection Agency, Office of Research and Development, National Exposure Research Laboratory , Research Triangle Park , North Carolina , USA.
J Toxicol Environ Health A. 2013;76(13):815-26. doi: 10.1080/15287394.2013.821395.
A mouse assay for measuring the relative bioavailability (RBA) of arsenic (As) in soil was developed. In this study, results are presented of RBA assays of 16 soils, including multiple assays of the same soils, which provide a quantitative assessment of reproducibility of mouse assay results, as well as a comparison of results from the mouse assay with results from a swine and monkey assay applied to the same test soils. The mouse assay is highly reproducible; three repeated assays on the same soils yielded RBA estimates that ranged from 1 to 3% of the group mean. The mouse, monkey, and swine models yielded similar results for some, but not all, test materials. RBA estimates for identical soils (nine test soils and three standard reference materials [SRM]) assayed in mice and swine were significantly correlated (r = 0.70). Swine RBA estimates for 6 of the 12 test materials were higher than those from the mouse assay. RBA estimates for three standard reference materials (SRM) were not statistically different (mouse/swine ratio ranged from 0.86-1). When four test soils from the same orchard were assessed in the mouse, monkey, and swine assays, the mean soil As RBA were not statistically different. Mouse and swine models predicted similar steady state urinary excretion fractions (UEF) for As of 62 and 74%, respectively, during repeated ingestion doses of sodium arsenate, the water-soluble As form used as the reference in the calculation of RBA. In the mouse assay, the UEF for water soluble As(V) (sodium arsenate) and As(III) (sodium [meta] arsenite) were 62% and 66%, respectively, suggesting similar absolute bioavailabilities for the two As species. The mouse assay can serve as a highly cost-effective alternative or supplement to monkey and swine assays for improving As risk assessments by providing site-specific assessments of RBA of As in soils.
建立了一种用于测量土壤中砷（As）相对生物利用度（RBA）的小鼠测定法。在这项研究中，报告了 16 种土壤的 RBA 测定结果，包括对同一土壤的多次测定，这提供了对小鼠测定结果重现性的定量评估，以及将小鼠测定结果与应用于相同测试土壤的猪和猴测定结果进行比较。小鼠测定法具有高度的重现性；对同一土壤进行了三次重复测定，得到的 RBA 估计值在组平均值的 1%至 3%之间。对于某些但不是所有测试材料，小鼠、猴子和猪模型的结果相似。在小鼠和猪中测定的相同土壤（九种测试土壤和三种标准参考物质[SRM]）的 RBA 估计值显著相关（r = 0.70）。猪对 12 种测试材料中的 6 种的 RBA 估计值高于小鼠测定值。三种标准参考物质（SRM）的 RBA 估计值无统计学差异（鼠/猪比值范围为 0.86-1）。当在小鼠、猴子和猪测定中评估来自同一果园的四种测试土壤时，土壤 As 的 RBA 平均值无统计学差异。在重复摄入砷酸钠（用作 RBA 计算参考的水溶性 As 形式）期间，小鼠和猪模型分别预测出相似的砷稳态尿排泄分数（UEF）为 62%和 74%。在小鼠测定中，水溶性 As(V)（砷酸钠）和 As(III)（亚砷酸钠）的 UEF 分别为 62%和 66%，表明两种 As 物种的绝对生物利用度相似。小鼠测定法可以作为猴子和猪测定法的高成本效益替代或补充方法，通过提供土壤中 As 的 RBA 的现场特定评估，改善 As 风险评估。
