Seite - 95 - in Freshwater Microplastics - Emerging Environmental Contaminants?

be the most abundant in Taihu Lake likely due to a low biodegradability of the material [31]. In the freshwaters of Wuhan, PET, PP, PE, PA, and PS were identified, and PET and PP were more abundant [32]. From the estuaries of Jiaojiang, Oujiang, and Minjiang, selected microplastics were found mostly PP and PE [33], which agrees with the result from the Three Gorges Reservoir. Frequent detection of PP and PEwas also reported inmany otherworks [36, 45, 69, 70]. This can be related to their lowdensity,meaning these polymer types are buoyant and readily transportedwithwater. Inaddition, a largerglobaldemand for PEandPPmakes themmoreprevalent in the environment. 4 Conclusions Inland waters are facing similar issues as marine environments with regard to microplastics. Analysis suggests that inlandwaters inmanyAsian countries have ahighrisk tobepollutedbymicroplastics.However,only limitedworkshavebeen performed in investigatingmicroplastic occurrence in inland waters in Asia cur- rently. Available researches have demonstrated the presence of microplastics in lakes, reservoirs, and river estuaries.Theabundancesofmicroplastics in theThree GorgesReservoir andTaihuLake inChina are among thehighest reporteddata in inland waters worldwide. Relatively high abundance of microplastic was also Table 2 Advantages and limitations of commonly used techniques for the identification of microplastics fromenvironmental samples Technique Size Advantages Limitations ATR-FTIR >1mm Easysimplepreparation; lowcost Unable to identify small sam- ples; unsuitable for convexpar- ticles or severely agedor contaminated samples μ-FTIR >10μm Suitable for small samples Sample preparation is complex; unable to analyze polyamides; high cost FPA-based μ-FTIR >20μm Suitable for small samples; no need for visual sorting Timeconsuming; high cost Raman spectroscopy >1μm Suitable for very small samples; lowerwater interference Sensitive tofluorescence inter- ference; laser-induceddegrada- tion; high cost CARSc >1μm Applicable to livingorganisms; minimal or no sample prepara- tion; strong signal; less interference Veryhigh cost Pyr-GC/MS >0.1mg Organic plastic additive canbe analyzed Destructive; time consuming ATR attenuated total reflectance, FPA focal plane array, CARS coherent anti-Stokes Raman scattering Microplastic Pollution in InlandWaters FocusingonAsia 95