Microplastics and particulate matter: assessment of atmospheric pollution in the Region of Hortênsias, Brazil

Atmospheric pollution is one of the main consequences of anthropogenic activities in the environment. The insertion of particles suspended in the air, which are composed of dust, fumes, microplastics, and aerosols emitted by industries, vehicles, and constructions, alters the quality of the environment they are inserted into, impacting both human health and the environment. Therefore, this study aimed to identify the atmospheric particles that may influence the air quality in the Region of Hortênsias (municipalities of Canela and Gramado) in Rio Grande do Sul state. The concentrations of the particulate matter PM2.5 and PM2.5-10 were evaluated at two sites from April 2021 to April 2022. The fine and coarse particulate matter sampler (FCS) was used to collect samples at the site located in Canela. In Gramado, besides the FCS, a dichotomous sampler was also used. The filters were observed under a microscope to evaluate the presence of polymeric material. The selected particles were then analyzed by scanning electron microscopy (SEM) coupled with energy-dispersive x-ray spectroscopy (EDS). Six samples of PM2.5 did not meet the air quality standards recommended by the World Health Organization guideline. The results demonstrated low air quality, and the microscopic analysis detected the presence of particles with polymeric material characteristics. These particles suggest traces of microplastics, in addition to the presence of vehicular soot and fly ash when analyzed by SEM/EDS.