饲料中新型卤代持久性有机污染物高通量筛查及其靶向甄别研究

The animal feeds play an important role in the food chain of feeds-animals-humans. However, the occurrence of emerging halogenated persistent organic pollutants (EHPOPs), which act like legacy POPs, are still unknown in the research field of feed safety in China. The feed safety requires more and more knowledge about these EHPOPs. Nowadays, both the explosive growth of chemicals and the complex matrix of animal feeds make it extremely hard to monitor every EHPOPs in feeds. Focusing on evaluating the persistence and bioaccumulative capacity of chemicals, the quantitative structure property relationships (QSPRs) model will be used to quickly screen the halogenated compounds from both the national and international chemical inventories in the present project. And for the first time, this project will calculate the binding affinities between the halogenated compounds and the bovine serum albumin, and assess their potential bioaccumulative capacities. Together with the compounds’ production volume and usage information, it will be able to select the high priority EHPOPs and then to infer their possible occurrence in corresponding animal feeds. In the next step, we will collect target feeds on a worldwide scale and identify the selected EHPOPs. This project will combine theoretical evaluation with practical sample identification, comprehensively to screen the EHPOPs in animal feeds, which will change the traditional approach of “from pollution to investigation”. The approach developed in the present project will put forward a new method and new concept in feed safety precaution.

饲料是“饲料-动物-人体”食物链中污染物的源头，国内对于饲料中具有类POPs特性的新型卤代持久性有机污染物(EHPOPs)研究尚为空白。EHPOPs在环境中层出不穷，单纯“追赶公约中POPs”已不能满足饲料安全的监管需求，逐一对饲料中潜在EHPOPs甄别也很难实现。本项目拟通过定量构效关系(QSPRs)模型对小分子卤代化合物进行生物富集能力和持久性的高通量筛选；同时完善原有模型主要通过亲脂性预测富集能力的机制，通过与血清蛋白对接，构建化学品蛋白亲和力与生物富集能力的相关性模型，筛选通过亲蛋白途径富集的EHPOPs；根据筛选到的EHPOPs的产量、用途等信息，确定目标EHPOPs，靶向采集饲料基质并分析其赋存。本项目结合理论计算和实际样品分析，全面筛选饲料中EHPOPs，改变传统上“从发现到监控”的常规模式，为建立饲料安全预警体系提供新思路和新方法。

饲料是“饲料-动物-人体”食物链中污染物的源头。本研究针对国内外饲料中具有POPs特性的新型卤代持久性有机污染物(EHPOPs)的来源、赋存及转化研究缺乏的现状，系统开展饲料中EHPOPs筛查、赋存特征解析、关键风险因子识别等研究工作，结合理论计算和实际样品分析，全面筛选饲料中EHPOPs，改变传统的“从发现到监控”的常规模式。首先围绕《斯德哥尔摩公约》中产量高、具有不同物理化学性质的几类污染物，如多溴二苯醚（PBDEs）和全氟化合物（PFASs），识别其赋存特征，明确含量水平，解析污染来源，通过ComTox计算毒理高性能平台进行基于分子动力学模拟的毒性效应分析。进一步针对《斯德哥尔摩公约》中化合物受到管控后其替代品使用较多的现状，考虑分子结构相似性筛选后续目标化合物。对饲料中短链PFASs、新型溴代阻燃剂（NBFRs）和有机磷酸酯（OPEs）等传统POPs替代品的分析方法和赋存进行了研究。研究发现，OPEs含量水平是PBDEs7.8倍，其二酯转化产物含量水平与母体化合物相当，毒性作用甚至高于母体化合物。在多类饲料（如植物源饲料原料）中，短链PFASs为主要赋存单体。POPs新型替代产品在海洋源性饲料中赋存广泛。最后，提出了一种系统的评价“饲料-动物-人体”食物链不同节点，EHPOPs污染风险排序方法、EHPOPs在食物链中传递风险关键因子、复合评价的手段，为建立饲料安全预警体系提供新思路和新方法。