Department of Earth Sciences, University of Gothenburg, Guldhedsgatan 5A, 413 20, Gothenburg, Sweden.
Chemosphere. 2021 Feb;264(Pt 1):128453. doi: 10.1016/j.chemosphere.2020.128453. Epub 2020 Oct 1.
The global plastic contamination is one of the major challenges facing mankind as plastic is ubiquitously present in all environmental compartments. In contrast to freshwater and marine environments, plastic contamination of agricultural soils was only recently subject to investigations although it represents a significant amount (14%) of the global plastic pollution. Of concern is the vertical migration of plastic particles in agricultural soils and plastic-induced enhancement of pesticide transport towards underlying groundwater systems. To assess the risk of the large plastic inventory in agricultural soils for groundwater systems and drinking water supplies, this review critically synthesizes the current knowledge of the plastic mobility and plastic-pesticide interactions in agricultural soils, identifies future research directions and evaluates associated analytical challenges. The reviewed studies provide consistent evidence for vertical migration of plastic in agricultural soils towards aquifer systems, especially for sub-micrometer sized plastic particles, analogously to the well-known migration of natural particles in the sub-micrometer range (colloids). The reviewed investigations also showed that plastic changes the sorption behavior of pesticides in agricultural soils and enhances their transport towards underlying groundwater systems. Hence, the deposited plastic in agricultural soils likely poses a major risk for underlying aquifers and drinking water supplies that rely on groundwater resources below farmlands to be contaminated by plastic and pesticides. This demonstrates that improved regulatory measures are necessary regarding the general usage of plastic in the farming process to protect aquifers and drinking water supplies from plastic and pesticide contamination and to avoid a potential human health hazard.
全球塑料污染是人类面临的主要挑战之一，因为塑料无处不在，存在于所有环境介质中。与淡水和海洋环境相比，农业土壤中的塑料污染直到最近才受到关注，尽管它占全球塑料污染的 14%。令人担忧的是，塑料颗粒在农业土壤中的垂直迁移以及塑料对农药向地下含水层系统迁移的增强作用。为了评估农业土壤中大量塑料库存对地下水系统和饮用水供应的风险，本综述批判性地综合了当前关于农业土壤中塑料迁移性和塑料-农药相互作用的知识，确定了未来的研究方向，并评估了相关的分析挑战。综述研究提供了一致的证据表明，塑料在农业土壤中垂直迁移到含水层系统，特别是对于亚微米大小的塑料颗粒，类似于众所周知的亚微米范围内天然颗粒（胶体）的迁移。综述调查还表明，塑料改变了农药在农业土壤中的吸附行为，并增强了它们向地下含水层系统的迁移。因此，农业土壤中沉积的塑料可能对地下含水层和依赖农田以下地下水资源的饮用水供应构成重大风险，因为塑料和农药可能会污染这些含水层和饮用水供应。这表明，为了保护含水层和饮用水供应免受塑料和农药污染，避免潜在的人类健康危害，有必要对农业生产过程中塑料的一般使用采取更严格的监管措施。
