Occurrence, removal and potential threats associated with microplastics in drinking water sources

近年来微塑料作为饮用水中的新兴污染物引起了国内外研究的广泛关注。本文中,我们基于已有文献从水处理的角度综述了它们的产生和去除情况,在此基础上进一步考虑了这些在饮用水水源中日益增加的人为颗粒的潜在威胁。文章从大量水环境微塑料监测研究论文中筛选出与饮用水水源相关的文献共53篇,探究微塑料在饮用水水源中的存在。我们根据这些文章中微塑料的采样方法和表示单位对其在水中的含量结果进行了分类讨论后发现,桶装水采样比网采样能够更多地收集到水中的微塑料,其结果表明常规水源中微塑料的含量中位数为2.2×103·m-3,而这些调研识别出的微塑料尺寸通常为50 μm以上的成分。由于微塑料的惰性,饮用水工艺对其处理效率基本是可以确定的,文献调研表明饮用水处理厂中多重处理后的微塑料去除效率较高。在混凝、沉淀和过滤后,几乎所有超过10μm 的微塑料都能被除去,对于较小的MP (>1μm),通常也能实现 80%以上的去除率。基于以上调研,我们提出不同尺寸大小的微塑料对饮用水水源的威胁:1) 对饮用水水源中存在的尺寸较大的微塑料(通常在20 μm以上)而言,其可能作为是潜在病原菌的携带者同时影响水源中抗生素抗性基因的传播; 2) 微塑料降解过程中产生的小粒径塑料(如纳塑料等)及溶解性有机碳的释放对饮用水水源的威胁。此外,微塑料在水环境中的广泛存在,由于饮用水水源的匮乏,污水、雨水和海水等也在世界各地越来越多作为备用饮用水水源,我们也对其中广泛存在的微塑料的存在和去除进行了讨论,并探讨了这些特殊水源中的微塑料的独特潜在威胁。

Abstract:Microplastics(MPs) have gained increasing attention as an emerging contaminant in drinkingwater. However, there is no definitive conclusion on the deleterious effects ofMPs on human health. Herein, we consider the potential threats of theseanthropogenic particles that have been increasingly found in drinking watersources (DWSs) based on reviewing their occurrence and removal from a watertreatment perspective. As revealed by 53 publications on MP presence inconventional DWSs, bulk sampling can better reflect the current knowledge onthe pollution in DWSs; the median MP concentration in conventional watersources was 2.2 × 103 items m3 with the size of particles identified usually >50 μm.Next, the removal efficiency of MPs across multiple barriers in drinking watertreatment plants was also elaborated. Almost all MPs (>10 μm) were removedafter coagulation, sedimentation and filtration processes. For smallerMPs(>1 μm), removal rates of >80% were typically observed. Twosize-dependent threats associated with MPs in DWSs were identified: 1) theincreased probability of the accumulation of potential pathogenic bacteria andthe transmission of antibiotic resistance genes where larger MPs in DWSs mayserve as important carriers; 2) the release of nanoplastics and dissolvedorganic carbon from the photo degradation process of MPs. Additionally, MPs in alternativeDWSs were given special attention due to their potential to accumulate MPs. Thereview provides new information for practitioners and scientists alike withrespect to the potential threats posed by MPs in DWSs.

1.jpg

下载

办公室:同济大学四平路校区环境科学与工程学院明净楼413A室

实验室:同济大学四平路校区城市污染控制国家工程研究中心大楼201A

邮箱:123lwyktz@tongji.edu.cn

电话:18017982085 ;13162523930