Microplastics in the Sinos River, Southern Brazil

Abstract

Several sources of pollution affect aquatic ecosystems. In both marine and freshwater, the impacts caused by solid waste, more specifically those of plastic origin, are among those that most concern the quality of these environments. Microplastics are large polymeric molecules, and once present in the environment, they can interact and have caused harmful effects on living organisms. The Sinos River, located in the state of Rio Grande do Sul, Brazil, is the main water body of the basin. Supplies more than 1 million inhabitants and constantly receives untreated domestic and industrial effluent discharges. The present study aimed to evaluate microplastics occurrence in water and sediment samples from three sites along the Sinos River and chemically characterize the particles using Scanning Electron Microscopy (SEM) and Dispersive Energy Spectroscopy (EDS) analysis. Microparticles, mostly fibers, were found in all samples and all three sites, demonstrating that they are present in the environment. Microparticles were found in all samples and sites. Particle sizes ranged from 67 µm - 4.2 mm. The concentrations of microparticles obtained were 65 mp/L of water and 7.2 mp/mL of sediment and microfibers were predominant. New studies may contribute with more precision in the diagnosis and determination of the sources inflows of these contaminants along the basin.

Keywords: Microplastic, Plastic Pollution, SEM/EDS, Sinos River Basin