Rijks Instituut voor Volksgezondheid en Milieu (Dutch National Institute for Public Health and the Environment), Bilthoven, The Netherlands.
Environ Toxicol Chem. 2012 Sep;31(9):2175-88. doi: 10.1002/etc.1923. Epub 2012 Aug 1.
Species sensitivity distributions (SSDs) quantify fractions of species potentially affected in contaminated environmental compartments using test species sensitivity data. The present study quantitatively describes associations between predicted and observed ecological impacts of contaminant mixtures, based on monitoring data of benthic macroinvertebrates. Local mixture toxic pressures (multisubstance potentially affected fraction of species [msPAF]) were quantified based on measured concentrations of 45 compounds (eight metals, 16 chlorinated organics, mineral oil, 16 polycyclic aromatic hydrocarbons, four polychlorinated biphenyls), using acute as well as chronic 50%-effective concentration-based SSD-modeling combined with bioavailability and mixture modeling. Acute and chronic toxic pressures were closely related. Generalized linear models (GLMs) were derived to describe taxon abundances as functions of environmental variables (including acute toxic pressure). Acute toxic pressure ranged from 0 to 42% and was related to abundance for 74% of the taxa. Habitat-abundance curves were generated using the GLMs and Monte Carlo simulation. Predicted abundances for the taxa were associated with acute mixture toxic pressure in various ways: negative, positive, and optimum abundance changes occurred. Acute toxic pressure (msPAF) was associated almost 1:1 with the observed fraction of taxa exhibiting an abundance reduction of 50% or more. The findings imply that an increase of mixture toxic pressure associates to increased ecological impacts in the field. This finding is important, given the societal relevance of SSD model outputs in environmental policies.
物种敏感度分布（SSD）通过测试物种敏感度数据，量化受污染环境中潜在受影响物种的比例。本研究基于底栖大型无脊椎动物监测数据，定量描述了污染物混合物的预测生态影响与实际观测生态影响之间的关联。基于 45 种化合物（8 种金属、16 种氯化有机物、矿物油、16 种多环芳烃、4 种多氯联苯）的实测浓度，利用急性和慢性基于 50%有效浓度的 SSD 模型结合生物有效性和混合物模型，量化了局部混合物毒性压力（多物质潜在受影响物种分数 [msPAF]）。急性和慢性毒性压力密切相关。推导了广义线性模型（GLMs），以描述分类群丰度作为环境变量（包括急性毒性压力）的函数。急性毒性压力范围从 0 到 42%，与 74%的分类群丰度相关。使用 GLMs 和蒙特卡罗模拟生成栖息地丰度曲线。使用 GLMs 预测的分类群丰度与急性混合物毒性压力以各种方式相关联：出现负、正和最佳丰度变化。急性毒性压力（msPAF）几乎与观察到的 50%或更多丰度减少的分类群比例呈 1:1 相关。这些发现意味着混合物毒性压力的增加与现场生态影响的增加有关。鉴于 SSD 模型输出在环境政策中的社会相关性，这一发现非常重要。
