Assessment of chemical screening outcomes based on different partitioning property estimation methods.
Assessment of chemical screening outcomes based on different partitioning property estimation methods.
复制标题
基于不同分配特性估计方法的化学筛选结果评估。
DOI：
10.1016/j.envint.2010.03.010
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发表时间：
2010
影响因子：
11.8
通讯作者：
K. Goss
中科院分区：
文献类型：
--
作者：
Xianming Zhang;T. Brown;F. Wania;E. Heimstad;K. Goss
筛选被广泛用于根据化学品的潜在环境危害，如持久性、生物累积性（B）、毒性和远距离迁移潜力（LRTP）等属性所示，对化学品进行优先排序。B和LRTP的许多筛选方法都依赖于根据化学品在辛醇和水（KOW）、空气和水（KAW）以及辛醇和空气（KOA）之间的平衡分配系数与阈值的比较对化学品进行分类。由于实验值的性质大多是不可用的大量的化学物质被筛选，使用定量结构-性质关系（QSPR）和其他计算化学方法变得不可或缺。不同方法的预测往往会有很大的偏差，有缺陷的预测可能会导致错误的阳性/阴性分类。我们预测了529种化学物质的分配特性，这些化学物质是从以前的优先级排序工作中挑选出来的，使用了四种预测方法EPI Suite，COSMOtherm和ABSOLV。这四组预测被用来根据各种LRTP和B标准筛选化学品。基于四种方法的筛选结果仅对约70%的化学品是一致的。为了进一步评估估算环境相划分的方法是否有影响，分别基于单参数和多参数线性自由能关系筛选了110种化学品的子集，以确定北极污染潜力。在110种化学品中，有5种被分为不同的类别。依赖于决定化学品的预测特性是否福尔斯在阈值的任何一侧的筛选和分类方法可能会导致大量的假阳性/阴性结果。因此，我们建议，筛选应该是基于数字的危害或风险估计，承认并明确考虑到预测属性的不确定性。
Screening is widely used to prioritize chemicals according to their potential environmental hazard, as expressed in the attributes of persistence, bioaccumulation (B), toxicity and long range transport potential (LRTP). Many screening approaches for B and LRTP rely on the categorization of chemicals based on a comparison of their equilibrium partition coefficients between octanol and water (KOW), air and water (KAW) and octanol and air (KOA) with a threshold value. As experimental values of the properties are mostly unavailable for the large number of chemicals being screened, the use of quantitative structure–property relationships (QSPRs) and other computational chemistry methods becomes indispensable. Predictions by different methods often deviate considerably, and flawed predictions may lead to false positive/negative categorizations. We predicted the partitioning properties of 529 chemicals, culled from previous prioritization efforts, using the four prediction methods EPI Suite, SPARC, COSMOtherm, and ABSOLV. The four sets of predictions were used to screen the chemicals against various LRTP and B criteria. Screening results based on the four methods were consistent for only ∼70% of the chemicals. To further assess whether the means of estimating environmental phase partitioning has an impact, a subset of 110 chemicals was screened for elevated arctic contamination potential based on single-parameter and poly-parameter linear free energy relationships respectively. Different categorizations were observed for 5 out of 110 chemicals. Screening and categorization methods that rely on a decision whether a chemical's predicted property falls on either side of a threshold are likely to lead to a significant number of false positive/negative outcomes. We therefore suggest that screening should rather be based on numerical hazard or risk estimates that acknowledge and explicitly take into account the uncertainties of predicted properties.