Abstract：
Plastics and, in particular, microplastics (MPs) (< 5 mm) are emerging environmental pollutants responsible for interconnected risks to environmental, human, and animal health. The livestock sector is highly affected by these contaminants, with 50-60 % of the foreign bodies found in slaughtered domestic cattle being recognized as plastic-based materials. Additionally, microplastics were recently detected inside ruminant bodies and in their feces. MPs presence in ruminants could be explained by the intensive usage of plastic materials on farms, in particular to store feeds (i.e. to cover horizontal silos and to wrap hay bales). Although feed could be one of the main sources of plastics, especially of microplastics, a specific protocol to detect them in ruminant feeds is not actually present. Hence, the aim of this study was to optimize a specific protocol for the extraction, quantification, and identification of five microplastic polymers (high-density polyethylene, low-density polyethylene, polyamide fibers/particles, polyethylene terephthalate and polystyrene) from feeds typically used in ruminant diets (corn silage, hay, high protein feedstuff and total mixed ration). Several combinations of Fenton reactions and KOH digestion were tested. The final extraction protocol involved a KOH digestion (60 °C for 24 h), followed by two/three cycles of Fenton reactions. The extraction recoveries were of 100 % for high-density, low-density polyethylene, polyamide particles, and polystyrene and higher than 85 % for polyethylene terephthalate and polyamide fibers. Finally, the optimized protocol was successfully applied in the extraction of microplastics from real feed samples. All the feeds contained microplastics, particularly polyethylene, thus confirming the exposure of ruminants to MPs.
摘要：
塑料和,特别是,微塑料(MPs)(<5mm)是新兴的环境污染物，对环境造成相互关联的风险，人类,动物健康。畜牧业受到这些污染物的高度影响，在屠宰的家畜中发现的异物中有50-60%被认为是塑料材料。此外,最近在反刍动物体内和粪便中发现了微塑料。国会议员在反刍动物中的存在可以通过农场大量使用塑料材料来解释，特别是存储提要(即，覆盖水平筒仓并包裹干草捆)。虽然饲料可能是塑料的主要来源之一，特别是微塑料，在反刍动物饲料中检测它们的具体方案实际上并不存在。因此，这项研究的目的是优化提取的具体方案，量化，和五种微塑料聚合物(高密度聚乙烯，低密度聚乙烯，聚酰胺纤维/颗粒，聚对苯二甲酸乙二醇酯和聚苯乙烯）来自反刍动物饮食中通常使用的饲料（玉米青贮饲料，干草,高蛋白饲料和总混合日粮)。测试了Fenton反应和KOH消化的几种组合。最终的提取方案涉及KOH消化（60°C，24小时），随后是两个/三个循环的Fenton反应。高密度的提取回收率为100%,低密度聚乙烯，聚酰胺颗粒，和聚苯乙烯和高于85%的聚对苯二甲酸乙二醇酯和聚酰胺纤维。最后,优化的方案已成功应用于从实际饲料样品中提取微塑料。所有的饲料都含有微塑料，特别是聚乙烯，从而证实了反刍动物接触国会议员。
