Methods for Studying Microplastic Pollution in Natural Waters: Current State and Recommendations

Abstract

Assessing contamination of natural waters with microplastic particles includes several methodological stages – sampling, particle extraction, chemical identification and quantification. Currently, different research groups use different methods based on capabilities, available equipment and research objectives, which leads to erroneous estimates and inability to compare data. The article discusses modern approaches for correctly determining the content of microplastics in natural waters in the context of harmonization of methods for studying microplastics and subsequent standardization of monitoring methods. Quality assurance and quality control (QA/QC) issues are addressed separately, and specific QA/QC steps are presented for sampling and sample processing procedures, taking into account the small size of microplastics and the high risk of external contamination. The article also details what data must be presented in scientific articles and reports, thereby providing a basis for comparing the results of different scientific groups and creating a global database. The article also provides methodological recommendations for sampling and sample analysis to assess the level of of microplastic pollution in surface waters.