Evolution & Ecology Research Centre, School of Biological, Earth & Environmental Sciences, University of New South Wales, Sydney, NSW 2052, Australia.
Evolution & Ecology Research Centre, School of Biological, Earth & Environmental Sciences, University of New South Wales, Sydney, NSW 2052, Australia.
Environ Pollut. 2018 Mar;234:552-561. doi: 10.1016/j.envpol.2017.11.085. Epub 2017 Dec 21.
Microplastics and fibres occur in high concentrations along urban coastlines, but the occurrence of microplastic ingestion by fishes in these areas requires further investigation. Herein, the ingestion of debris (i.e., synthetic and natural fibres and synthetic fragments of various polymer types) by three benthic-foraging fish species Acanthopagrus australis (yellowfin bream), Mugil cephalus (sea mullet) and Gerres subfasciatus (silverbiddy) in Sydney Harbour, Australia has been quantified and chemically speciated by vibrational spectroscopy to identify the polymer type. Ingested debris were quantified using gut content analysis, and identified using attenuated total reflectance Fourier transform infrared (ATR-FTIR) and Raman microspectroscopies in combination with principal component analysis (PCA). The occurrence of debris ingestion at the time of sampling ranged from 21 to 64% for the three species, and the debris number ranged from 0.2 to 4.6 items per fish for the different species, with ∼53% of debris being microplastic. There was a significant difference in the amount of debris ingested among species; however, there was no difference among species when debris counts were standardised to fish weight or gut content weight, indicating that these species ingest a similar concentration of debris relative to their ingestion rate of other material. ATR-FTIR microspectroscopy successfully identified 72% of debris. Raman spectroscopy contributed an additional 1% of successful identification. In addition, PCA was used to non-subjectively classify the ATR-FTIR spectra resulting in the identification of an additional 9% of the debris. The most common microplastics found were polyester (PET), acrylic-polyester blend, and rayon (semi-synthetic) fibres. The potential of using Raman microspectroscopy for debris identification was investigated and provided additional information about the nature of the debris as well as the presence of specific dyes (and hence potential toxicity).
微塑料和纤维在城市沿海地区高度集中，但这些地区鱼类摄入微塑料的情况仍需进一步调查。本研究定量分析了澳大利亚悉尼港三种底栖觅食鱼类（黄鳍鲷、褐点石斑鱼和银鲳）摄入的碎片（即合成纤维和天然纤维以及各种聚合物类型的合成碎片），并通过振动光谱对其进行化学物质鉴别，以确定聚合物类型。采用肠道内容物分析法对摄入的碎片进行定量分析，并用衰减全反射傅里叶变换红外（ATR-FTIR）和拉曼显微镜结合主成分分析（PCA）对其进行鉴定。在采样时，三种鱼类摄入的碎片数量占比为 21%至 64%，不同鱼类的碎片数量为 0.2 至 4.6 个/条，其中约 53%的碎片为微塑料。三种鱼类摄入的碎片数量存在显著差异；然而，当将碎片数量标准化为鱼体重或肠道内容物重量时，三种鱼类之间没有差异，这表明这些鱼类摄入的碎片浓度与其对其他物质的摄食率相当。ATR-FTIR 显微镜成功鉴定了 72%的碎片。拉曼光谱则额外贡献了 1%的成功识别率。此外，PCA 还用于非主观地对 ATR-FTIR 光谱进行分类，从而进一步识别出 9%的碎片。发现的最常见微塑料为聚酯（PET）、丙烯纤维-聚酯共混纤维和人造丝（半合成）纤维。还对拉曼显微镜用于碎片识别的潜力进行了研究，提供了有关碎片性质以及特定染料（进而潜在毒性）存在的额外信息。
