Identification of microplastics in the aquatic environment, or in the presence of algae Chlorella sp., by comparison of biophotonic methods

Microplastics (MPs) are emerging pollutants in our environment. However, their identification under real environmental conditions remains challenging, particularly in the case of MPs found in water sources, where other organic materials, such as algae, are present. Custom-prepared MPs (PET, PS, PLA) - commonly found in the aquatic environment – were tested in the dry state, in the water colloidal solutions, and/or in the presence of algae Chlorella sp. A multi-method approach, comparing different biophotonic methods, including FTIR, Raman (conventional or Surface Enhanced Raman Spectroscopy (SERS)) and spectrally-resolved confocal fluorescence microscopy methods were employed. We tested the capabilities of the applied methods to detect the presence of MPs in complex environmental conditions and thus the possibilities for their use for an in-situ effective monitoring. • Identification of microplastics remains challenging in the aquatic environment and/or in the presence of organic material. • A multimethod approach is used including FTIR, Raman (also SERS) and spectrally-resolved fluorescence microscopy. • The presence of microplastics is detected in complex environmental conditions to allow their in-situ effective monitoring.