Naziri Andrea, Mina Theoni, Manoli Kyriakos, Beretsou Vasiliki G, Christou Anastasis, Michael Costas, Agathokleous Evgenios, Fatta-Kassinos Despo
Nireas - International Water Research Center, University of Cyprus, P.O. Box 20537, CY-1678 Nicosia, Cyprus; Department of Civil and Environmental Engineering, School of Engineering, University of Cyprus, P.O. Box 20537, CY-1678 Nicosia, Cyprus.
Nireas - International Water Research Center, University of Cyprus, P.O. Box 20537, CY-1678 Nicosia, Cyprus.
Sci Total Environ. 2023 Sep 20;892:164618. doi: 10.1016/j.scitotenv.2023.164618. Epub 2023 Jun 5.
To address water shortage challenges, treated wastewater is used to meet the demand for irrigation water in several countries worldwide. Considering the presence of pollutants in treated wastewater, its use for land irrigation might have an impact in the environment. This review article focuses on the combined effects (or potential joint toxicity) of microplastics (MPs)/nanoplastics (NPs) and other environmental contaminants present in treated wastewater on edible plants after irrigation. Initially, the concentrations of MPs/NPs in wastewater treatment plant effluents and surface waters are summarized, indicating the presence of MPs/NPs in both water matrices (i.e., wastewater after receiving treatment and lakes/rivers). Then, the results of 19 studies related to joint toxicity of MPs/NPs and co-contaminants (e.g., heavy metals and pharmaceuticals) on edible plants, are reviewed and discussed. This concurrent presence may result in several combined effects on edible plants, e.g., rapid root growth, increase in antioxidant enzymes, decrease in photosynthetic rate and increased production of ROS. These effects, as discussed in the various studies on which this review is based, can generate antagonistic or even neutral impact on plants, depending on the size of MPs/NPs and their mixing ratio with the co-contaminants. However, a combined exposure of edible plants to MPs/NPs and co-contaminants can also lead to hormetic adaptive responses. The data reviewed and discussed herein may relieve overlooked environmental impacts of treated wastewater reuse and may be useful to address challenges related to the combined effects of MPs/NPs and co-contaminants on edible plants after irrigation. The conclusions drawn in this review article are relevant to both direct (i.e., treated wastewater irrigation) and indirect (i.e., discharging treated wastewater in surface waters used for irrigation purposes) reuse, and may contribute to the implementation of the European Regulation 2020/741 on the minimum requirements for water reuse.
为应对水资源短缺挑战，经处理的废水在世界上多个国家被用于满足灌溉用水需求。考虑到经处理的废水中存在污染物，将其用于土地灌溉可能会对环境产生影响。这篇综述文章聚焦于微塑料（MPs）/纳米塑料（NPs）与经处理的废水中存在的其他环境污染物对灌溉后可食用植物的联合效应（或潜在的联合毒性）。首先，总结了污水处理厂出水和地表水中MPs/NPs的浓度，表明这两种水体基质（即处理后的废水以及湖泊/河流）中均存在MPs/NPs。然后，对19项关于MPs/NPs与共污染物（如重金属和药物）对可食用植物联合毒性的研究结果进行了综述和讨论。这种同时存在可能会对可食用植物产生多种联合效应，例如根系快速生长、抗氧化酶增加、光合速率降低以及活性氧生成增加。正如本综述所依据的各项研究所讨论的，这些效应可能会对植物产生拮抗甚至中性影响，这取决于MPs/NPs的大小及其与共污染物的混合比例。然而，可食用植物同时暴露于MPs/NPs和共污染物也可能导致刺激适应性反应。本文所综述和讨论的数据可能有助于缓解经处理的废水回用被忽视的环境影响，并且可能有助于应对与MPs/NPs和共污染物对灌溉后可食用植物的联合效应相关的挑战。这篇综述文章得出的结论与直接回用（即经处理的废水灌溉）和间接回用（即将经处理的废水排放到用于灌溉目的的地表水中）均相关，并且可能有助于实施关于水回用最低要求的欧盟法规2020/741。
