Extraction of Microplastics from River Water in a Rotating Coiled Column Using a Water–Oil System

Abstract Determination of the microplastics content of natural waters is an important task in assessing the degree of water body pollution, identifying pollution sources, and evaluating potential risks for aquatic ecosystem inhabitants and water consumers. Solving this problem primarily falls within the realm of analytical chemistry, with separation methods for particles playing a crucial role. This work for the first time presents a potential application of the method of continuous-flow microplastic separation in a rotating coiled column using a water–oil system for assessing the microplastics content in river water. Microplastics in the extracted particle samples were determined by pyrolytic gas chromatography with mass spectrometric detection (pyro-GC–MS). A water sample from the Moskva River was analyzed. Using a water–castor oil system, 1.8 mg/L of suspended particles were extracted from the river water. A procedure for the digestion of the organic matter of the sample (30% H 2 O 2 ) reduced the mass of the extracted particles to 0.4 mg/L. The residual fraction was analyzed by optical microscopy. According to the pyro-GC–MS data, the total microplastics content in the test water sample was 109 µg/L, accounting for 1.4% of the total suspended particle content of the sample. Five types of microplastics were identified: polyethylene, polypropylene, acrylonitrile butadiene styrene, acryl–butadiene rubber, and polyethylene terephthalate, with polyethylene being the predominant type (97 µg/L). The proposed method offers promise for assessing the microplastics content in natural waters.