A systematic review of the methods used for sampling and analysis of microplastics in air and settled dust of indoor and outdoor environments in Iran

 Given the concern about the presence of microplastics in the air and settled dust, and the lack of a standard approach for their detection, it is necessary to investigate the methods and techniques used to study this type of pollution in Iran. Therefore, this study aimed to systematically review the methods and techniques used for sampling, quantification, and characterization of microplastics in the air and settled dust in indoor and outdoor environments in Iran.

 In this systematic review, the keywords Microplastic*, Air*, Atmosphere*, Dust, Indoor, Outdoor, Iran, and their corresponding Persian equivalents were searched until Dec 1, 2023, in Scopus, PubMed, Web of Science, Google Scholar, Magiran, and SID databases. Obtained articles from the databases were analyzed in order to find the eligible ones.

 Overall, 175 articles were found in the initial search, and after removing the duplicates and nonrelevant, 13 eligible articles were included in the study. In most of the studies, the samples were digested with H2O2, and the microplastics were mainly analyzed using a variety of microscopes and µRaman spectroscopy. The abundance of microplastics in the indoor environment was much higher than in the outdoor environment.

 The results of this study showed that there is the required equipment for the sampling and analysis of microplastics in air and settled dust in Iran, and these pollutants have been detected in both indoor and outdoor environments.