Kallenbach Emilie M F, Eriksen Tor Erik, Hurley Rachel R, Jacobsen Dean, Singdahl-Larsen Cecilie, Friberg Nikolai
NIVA Denmark Water Research, Njalsgade 76, 2300 Copenhagen S, Denmark.
University of Copenhagen, Universitetsparken 4, Copenhagen Ø, Denmark.
Microplast nanoplast. 2022;2(1):26. doi: 10.1186/s43591-022-00045-z. Epub 2022 Dec 8.
Microplastic is now ubiquitous in freshwater, sediment and biota, globally. This is as a consequence of inputs from, for example, waste mismanagement, effluents from wastewater treatment plants and surface runoff from agricultural areas. In this study, we investigated point source pollution of plastic to an upland stream, originating from a recycling plant that recycles polyethylene film in a remote area of Norway. Sediment (~2 kg) and macroinvertebrates (549 individuals in total) were sampled at one site upstream and two sites downstream of the recycling plant to study microplastic deposition and food web uptake. In total, 340 microplastic films were identified through a combination of visual and µFTIR analysis in the sediment samples. This corresponded to a concentration of 0.23 (± 0.057) items per g sediment upstream of the plastic recycling plant and 0.45 (± 0.017) and 0.58 (± 0.34) items per g downstream. The dominant plastic polymer was polyethylene, which increased significantly downstream of the plastic recycling plant. This indicates the role of the plastic recycling plant as a point source for microplastic in this catchment. Among the three sites investigated, a fairly constant concentration of polypropylene was found, indicating a diffuse source of polypropylene films across the catchment possibly relating to low-intensity agricultural land-use. Low levels of polyethylene were also observed upstream, which may be linked to either local or longer-distance atmospheric transport. Despite the considerable presence of microplastic in sediments, concentrations in macroinvertebrates were extremely low with only a single microplastic particle identified in the total of 549 macroinvertebrates-belonging to three different feeding groups-investigated. Our study suggests that: 1) microplastic pollution can be transferred to remote areas as unintended losses from recycling facilities, 2) remote areas with limited land-use pressure still have detectable levels of microplastic and 3) microplastic is only taken up by stream macroinvertebrates to a limited degree despite relatively high sediment concentrations, and thus there are no strong indications for ecological risks posed by microplastic to this ecological group at this location.
The online version contains supplementary material available at 10.1186/s43591-022-00045-z.
目前，微塑料在全球范围内的淡水、沉积物和生物群中无处不在。这是例如废物管理不善、污水处理厂的废水排放以及农业地区的地表径流等输入源造成的。在本研究中，我们调查了源自挪威偏远地区一家回收聚乙烯薄膜的回收厂的塑料对一条高地溪流的点源污染。在回收厂上游的一个地点和下游的两个地点采集了沉积物（约2千克）和大型无脊椎动物（总共549只个体），以研究微塑料的沉积和食物网摄取情况。通过对沉积物样本进行视觉分析和µFTIR分析相结合，总共鉴定出340片微塑料薄膜。这相当于塑料回收厂上游沉积物中微塑料的浓度为每克0.23（±0.057）个，下游分别为每克0.45（±0.017）个和0.58（±0.34）个。主要的塑料聚合物是聚乙烯，在塑料回收厂下游显著增加。这表明塑料回收厂在该集水区作为微塑料点源的作用。在所调查的三个地点中，发现聚丙烯的浓度相当恒定，这表明整个集水区存在聚丙烯薄膜的分散源，可能与低强度农业土地利用有关。上游也观察到低水平的聚乙烯，这可能与本地或长距离大气传输有关。尽管沉积物中存在大量微塑料，但在大型无脊椎动物中的浓度极低，在总共调查的549只属于三个不同摄食组的大型无脊椎动物中仅鉴定出一个微塑料颗粒。我们的研究表明：1）微塑料污染可以作为回收设施的意外损失转移到偏远地区；2）土地利用压力有限的偏远地区仍然存在可检测水平的微塑料；3）尽管沉积物浓度相对较高，但微塑料仅被溪流大型无脊椎动物有限程度地摄取，因此没有强烈迹象表明微塑料在此位置对该生态群体构成生态风险。
在线版本包含可在10.1186/s43591 - 022 - 00045 - z获取的补充材料。
