Department of Analytical Chemistry, Physical Chemistry and Chemical Engineering, University of Alcalá, Alcalá de Henares, E-28871 Madrid, Spain.
Departament of Biology, Faculty of Sciences, Universidad Autónoma de Madrid, Cantoblanco, E-28049 Madrid, Spain.
Sci Total Environ. 2020 Aug 10;729:138824. doi: 10.1016/j.scitotenv.2020.138824. Epub 2020 Apr 27.
We studied the occurrence of microplastics in sediments of artificially and non-artificially recharged lagoons from the network of endorheic wetlands called "La Mancha Húmeda", declared Biosphere Reserve by UNESCO. The particles sampled in this study covered the 25 μm-5 mm range. Films were the dominant microplastic typology in non-artificially recharged lagoons, while fibres and fragments were more abundant in those receiving wastewater. The concentration of microplastics in sediments reached up to 24.4 ± 5.2 microplastics/g, while plastic litter counts yielded <1 particle/g in non-wastewater receiving lagoons. Eleven types of plastic were identified using Micro-Fourier Transform Infrared Spectroscopy (micro-FTIR), the most abundant being the polyolefins polyethylene and polypropylene, and polyester and acrylic fibres. The statistical analysis of FTIR spectra confirmed the similarity between samples taken from recharged lagoons and wastewater treatment plant effluents. Overall, our results showed that endorheic lagoons are very sensitive to the accumulation of persistent pollutants, which include microplastics. The recharge of lagoons with wastewater effluents to maintain water levels, even if correctly treated according to current standards, is not a sustainable practice. Due to the closed character of endorheic basins, the continuous input of wastewater led to the accumulation of microplastics in sediments of wastewater receiving lagoons up to 40 times over non-recharged lagoons.
我们研究了被教科文组织宣布为生物圈保护区的“拉曼查湿地”内陆湿地网络中人工和非人工补给泻湖底泥中微塑料的出现情况。本研究中采样的颗粒覆盖了 25μm-5mm 的范围。在非人工补给的泻湖中，薄膜是主要的微塑料类型，而纤维和碎片在接收废水的泻湖中更为丰富。底泥中微塑料的浓度高达 24.4±5.2 个微塑料/g，而在未接收废水的泻湖中，塑料垃圾的计数<1 个/g。使用微傅里叶变换红外光谱（micro-FTIR）鉴定了 11 种类型的塑料，其中最丰富的是聚烯烃聚乙烯和聚丙烯，以及聚酯和丙烯酸纤维。FTIR 光谱的统计分析证实了从补给泻湖和废水处理厂废水中采集的样品之间的相似性。总的来说，我们的结果表明，内陆泻湖对包括微塑料在内的持久性污染物的积累非常敏感。用废水补给泻湖以维持水位，即使按照当前标准进行了正确处理，也不是一种可持续的做法。由于内陆盆地的封闭性，连续输入废水导致废水接收泻湖底泥中的微塑料积累量比未补给泻湖高 40 倍。
