Seite - 53 - in Freshwater Microplastics - Emerging Environmental Contaminants?

being developed using filter cascades that result in a size fractionation during the samplingand the reductionof thematrixburdenof thesmallmeshsizes [2]. Less frequently, a sampleof theaqueousphase is takenbelowthewater surface. Sampling of thewater column is carried out by direct filtration of thewater with submersible pumpsor is reportedby the acquisitionof batch samples [3, 4]. 1.1.2 SamplingofSediments There is no commonly accepted sampling strategy so far for sediment samples. First, the sediments samplesmust be divided into samples from the shoreline and the river- or lakebed. The collection of bed sediments by sediment grabs provides Fig.1 Possible strategiesdescribed in literature for theanalysisofmicroplastics in sediment and watersamplesstartingwiththesamplingtothereportof theresults.Thesamplepreparationissplit in pretreatment, the density separation, and the posttreatment of the separated microplastics. Fourier transform infrared spectroscopy (FTIR), scanning electronmicroscopy energy-dispersive X-ray spectroscopy (SEM-EDS), pyrolysis- or thermal desorption-gas chromatography/mass spectrometry (Pyr-GC/MS,TDS-GC/MS) are deployed for the analysis Analysis,Occurrence, andDegradation ofMicroplastics in theAqueous. . . 53