Comparative study of species sensitivity distributions based on non-parametric kernel density estimation for some transition metals
Comparative study of species sensitivity distributions based on non-parametric kernel density estimation for some transition metals
复制标题
基于非参数核密度估计的某些过渡金属物种敏感性分布的比较研究
DOI：
10.1016/j.envpol.2016.11.084
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发表时间：
2017
影响因子：
8.9
通讯作者：
Guo Wenjing
中科院分区：
文献类型：
--
作者：
Wang Ying;Feng Chenglian;Liu Yuedan;Zhao Yujie;Li Huixian;Zhao Tianhui;Guo Wenjing
元素周期表第四周期的过渡金属在水环境中广泛存在。它们往往会在一定浓度下发生，对水生生物和人类健康造成不利影响。通常，参数模型大多用于构建物种敏感性分布(SSD)，这会导致元素周期表中同一时期或同一组元素的水质标准(WQC)的比较可能不准确，结果可能会有偏差。为了解决这一不足，发展了非参数核密度估计(NPKDE)及其最优带宽和测试方法来建立SSD。与传统的正态密度估计和Logistic参数密度估计相比，NPKDE具有更好的拟合度、更强的稳健性和更好的预测性，用于构建SSD和推导过渡金属在元素周期表第四周期的急性HC5和WQC。第四阶段过渡金属的Hc5值由大到小的顺序是：Ti；，；，与元素周期表中的原子序数不成正比，不同金属的相对敏感物种也不同。结果表明，影响过渡金属毒性机制的因素除物理化学性质外，还有其他因素。该方法丰富了WQC的方法论基础。同时，也为水环境中同族、同时期金属的WQC推导和风险评估提供了一种相对创新、准确的方法，为水生生物的保护提供了支持。
Transition metals in the fourth period of the periodic table of the elements are widely widespread in aquatic environments. They could often occur at certain concentrations to cause adverse effects on aquatic life and human health. Generally, parametric models are mostly used to construct species sensitivity distributions (SSDs), which result in comparison for water quality criteria (WQC) of elements in the same period or group of the periodic table might be inaccurate and the results could be biased. To address this inadequacy, the non-parametric kernel density estimation (NPKDE) with its optimal bandwidths and testing methods were developed for establishing SSDs. The NPKDE was better fit, more robustness and better predicted than conventional normal and logistic parametric density estimations for constructing SSDs and deriving acute HC5 and WQC for transition metals in the fourth period of the periodic table. The decreasing sequence of HC5 values for the transition metals in the fourth period was Ti > Mn > V > Ni > Zn > Cu > Fe > Co > Cr(VI), which were not proportional to atomic number in the periodic table, and for different metals the relatively sensitive species were also different. The results indicated that except for physical and chemical properties there are other factors affecting toxicity mechanisms of transition metals. The proposed method enriched the methodological foundation for WQC. Meanwhile, it also provided a relatively innovative, accurate approach for the WQC derivation and risk assessment of the same group and period metals in aquatic environments to support protection of aquatic organisms.