Nolte Tom M, Ragas Ad M J
Department of Environmental Science, Institute for Water and Wetland Research, Radboud University Nijmegen, P.O. Box 9010, 6500 GL Nijmegen, The Netherlands.
Environ Sci Process Impacts. 2017 Mar 22;19(3):221-246. doi: 10.1039/c7em00034k.
Many organic chemicals are ionizable by nature. After use and release into the environment, various fate processes determine their concentrations, and hence exposure to aquatic organisms. In the absence of suitable data, such fate processes can be estimated using Quantitative Structure-Property Relationships (QSPRs). In this review we compiled available QSPRs from the open literature and assessed their applicability towards ionizable organic chemicals. Using quantitative and qualitative criteria we selected the 'best' QSPRs for sorption, (a)biotic degradation, and bioconcentration. The results indicate that many suitable QSPRs exist, but some critical knowledge gaps remain. Specifically, future focus should be directed towards the development of QSPR models for biodegradation in wastewater and sediment systems, direct photolysis and reaction with singlet oxygen, as well as additional reactive intermediates. Adequate QSPRs for bioconcentration in fish exist, but more accurate assessments can be achieved using pharmacologically based toxicokinetic (PBTK) models. No adequate QSPRs exist for bioconcentration in non-fish species. Due to the high variability of chemical and biological species as well as environmental conditions in QSPR datasets, accurate predictions for specific systems and inter-dataset conversions are problematic, for which standardization is needed. For all QSPR endpoints, additional data requirements involve supplementing the current chemical space covered and accurately characterizing the test systems used.
许多有机化学品本质上是可离子化的。在使用并释放到环境中后，各种归宿过程决定了它们的浓度，进而决定了水生生物接触这些化学品的情况。在缺乏合适数据的情况下，可以使用定量结构-性质关系（QSPRs）来估算这些归宿过程。在本综述中，我们从公开文献中收集了可用的QSPRs，并评估了它们对可离子化有机化学品的适用性。我们使用定量和定性标准，选择了用于吸附、（非）生物降解和生物富集的“最佳”QSPRs。结果表明，存在许多合适的QSPRs，但仍存在一些关键的知识空白。具体而言，未来应着重开发用于废水和沉积物系统中生物降解、直接光解以及与单线态氧反应的QSPR模型，以及其他反应性中间体的模型。存在适用于鱼类生物富集的QSPRs，但使用基于药理学的毒代动力学（PBTK）模型可以实现更准确的评估。不存在适用于非鱼类物种生物富集的QSPRs。由于QSPR数据集中化学和生物物种以及环境条件的高度变异性，对特定系统进行准确预测和数据集间转换存在问题，因此需要进行标准化。对于所有QSPR终点，额外的数据要求包括补充当前涵盖的化学空间，并准确表征所使用的测试系统。
