...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Environmental Science & Technology >Estimation of Lead and Arsenic Bioayailability Using a Physiologically Based Extraction Test
【24h】

Estimation of Lead and Arsenic Bioayailability Using a Physiologically Based Extraction Test

机译：使用基于生理的提取试验估算铅和砷的生物可利用性

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

The physiologically based extraction test (PBET) is an in vitro test system for predicting the bioavailability of metals from a solid matrix and incorporates gastrointestinal tract parameters representative of a human (including stomach and small intestinal pH and chemistry, soil-to-solution ratio, stomach mixing, and stomach emptying rates). For lead (Pb), the results of the PBET are linearly correlated with results from a Sprague-Dawley rat model (r~2 = 0.93 between in vitro and in vivo results, n = 7). For arsenic (As), the results of the PBET are overpredicting bioavailability study results in rabbit and primate models (2-11% difference between in vitro and in vivo results, depending on the animal model). The PBET was not designed to supplant bioavailability studies using animal models, but rather to estimate Pb and As bioavailability when animal study results are not available. Dissolution of Pb in the acidic stomach environment was strongly pH dependent; the extent of dissolution decreased by 65% when stomach pH was increased from 1.3 to 2.5. Arsenic solubility decreased by only 16% over the same pH range. Lead was removed from solution to a greater extent than As by neutralization during the small intestinal simulation, consistent with adsorption and precipitation reactions occurring for Pb-but not As-at neutral pH values. In addition to providing mechanistic explanations for controls on Pb and As bioavailability, the PBET allows estimates of site-specific Pb and As bioavailability from soil for the purpose of exposure assessment.
机译：基于生理的提取测试（PBET）是一种体外测试系统，用于预测固体基质中金属的生物利用度，并结合了代表人的胃肠道参数（包括胃和小肠的pH和化学性质，土壤与溶液的比例，胃混合和胃排空率）。对于铅（Pb），PBET的结果与Sprague-Dawley大鼠模型的结果线性相关（在体内和体外结果之间，r〜2 = 0.93，n = 7）。对于砷（As），PBET的结果高估了兔子和灵长类动物模型中的生物利用度研究结果（体外和体内结果之间的差异为2-11％，具体取决于动物模型）。 PBET的目的不是取代使用动物模型进行的生物利用度研究，而是在无法获得动物研究结果时估算Pb和As的生物利用度。铅在酸性胃环境中的溶解强烈地依赖于pH。当胃的pH值从1.3增加到2.5时，溶出度降低了65％。在相同的pH范围内，砷的溶解度仅降低了16％。在小肠模拟过程中，通过中和将铅从溶液中去除的程度比砷更大，这与在中性pH值下发生的Pb而不是As吸附和沉淀反应一致。除了提供控制铅和砷生物利用度的机械解释外，PBET还可以估算土壤中特定位点铅和砷的生物利用度，以进行暴露评估。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号