Department of Entomology, Michigan State University, East Lansing, Michigan 48824, United States.
Center for Advanced Microscopy, Michigan State University, East Lansing, Michigan 48824, United States.
Environ Sci Technol. 2020 May 5;54(9):5580-5588. doi: 10.1021/acs.est.0c00711. Epub 2020 Apr 23.
The emerging threat that microplastic pollution poses to soil and its biota necessitates the development of methods to detect microplastic ingestion by soil animals. Fluorescent staining with Nile red dye has proven to be effective at distinguishing microplastics from inorganic and some biological material but is not suitable for separating them from invertebrate remains. Here, we report on the development and validation of a novel fluorescent counterstaining technique for detection of microplastics within terrestrial invertebrate biomass and fecal material. After being stained with a blend of Calcofluor white and Evans blue dyes in addition to Nile red, ground arthropod biomass appeared blueish-purple, whereas different plastic polymers appeared red, green, and yellow when viewed under laser scanning confocal microscopy. Nonarthropod invertebrate biomass and fecal material were also distinguishable from plastic, though to a lesser extent. Our results highlight the value of this method for detecting microplastic ingestion by terrestrial invertebrates.
微塑料污染对土壤及其生物群构成的新出现威胁，需要开发方法来检测土壤动物对微塑料的摄入。尼罗红染料的荧光染色已被证明可有效区分微塑料与无机物质和一些生物材料，但不适合将其与无脊椎动物遗骸分离。在这里，我们报告了一种新的荧光复染技术的开发和验证，用于检测陆地无脊椎动物生物量和粪便中的微塑料。在用 Calcofluor white 和 Evans blue 染料与尼罗红混合染色后，研磨的节肢动物生物量呈现出蓝紫色，而不同的塑料聚合物在激光扫描共聚焦显微镜下观察时呈现红色、绿色和黄色。虽然程度较小，但也可以将非节肢动物无脊椎动物生物量和粪便材料与塑料区分开来。我们的结果强调了这种方法在检测陆地无脊椎动物对微塑料摄入方面的价值。
