• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Risk analysis >Variability in Physical Constant Parameter Values from Standard Data Sources and the Implication of this Variability for Risk Analysis
【24h】

Variability in Physical Constant Parameter Values from Standard Data Sources and the Implication of this Variability for Risk Analysis

机译：来自标准数据源的物理常数参数值的变异性及其对风险分析的意义

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

Physical property values are used in environmental risk assessments to estimate media and risk-based concentrations. Recently, however, considerable variability has been reported with such values. To evaluate potential variability in physical parameter values supporting a variety of regulatory programs, eight data sources were chosen for evaluation, and chemicals appearing in at least four sources were selected. There were 755 chemicals chosen. In addition, chemicals in seven environmentally important subgroups were also identified for evaluation. Nine parameters were selected for analysis—molecular weight (MolWt), melting point (MeltPt), boiling point (BoilPt), vapor pressure (VP), water solubility (AqSOL), Henry's law constant (HLC), octanol-water partition coefficient (Kow), and diffusion coefficients in air (Dair) and water (Dwater). Results show that while 71% of constituents had equal MolWts across data sources, < 3% of the constituents had equivalent parameter values across data sources for AqSOL, VP, or HLC. Considerable dissimilarity between certain sources was also observed. Furthermore, measures of dispersion showed considerable variation in data sets for Kow, VP, AqSOL, and HLC compared to measures for MolWt, MeltPt, BoilPt, or Dwater. The magnitude of the observed variability was also noteworthy. For example, the 95th percentile ratio of maximum/minimum parameter values ranged from 1.0 for MolWt to well over 1.0 x 10~6 for VP and HLC. Risk and exposure metrics also varied by similar magnitudes. Results with environmentally important subgroups were similar. These results show that there is considerable variability in physical parameter values from standard sources, and that the observed variability could affect potential risk estimates and perhaps risk management decisions.
机译：物理属性值用于环境风险评估中，以估计介质和基于风险的浓度。然而，近来已经报道了具有这样的值的相当大的可变性。为了评估支持各种监管计划的物理参数值的潜在可变性，选择了八个数据源进行评估，并选择了至少四个来源中出现的化学物质。选择了755种化学药品。此外，还确定了七个对环境重要的亚组中的化学物质进行评估。选择了9个参数进行分析-分子量（MolWt），熔点（MeltPt），沸点（BoilPt），蒸气压（VP），水溶性（AqSOL），亨利定律常数（HLC），辛醇-水分配系数（ Kow），以及在空气（Dair）和水（Dwater）中的扩散系数。结果表明，尽管71％的成分在所有数据源中具有相同的MolWts，但<3％的成分在AqSOL，VP或HLC的数据源中具有相等的参数值。在某些来源之间也观察到了很大的不同。此外，与MolWt，MeltPt，BoilPt或Dwater的测量值相比，Kow，VP，AqSOL和HLC的色散测量值数据集存在很大差异。观察到的变异性的大小也值得注意。例如，最大/最小参数值的第95个百分比在MolWt的1.0到VP和HLC的1.0 x 10〜6以上。风险和敞口指标也变化了相似的幅度。对环境重要的亚组的结果相似。这些结果表明，标准来源的物理参数值存在相当大的可变性，并且观察到的可变性可能会影响潜在的风险估计，甚至可能影响风险管理决策。

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