Caracterización y cuantificación de microplásticos presentes en el río Machángara de la ciudad de Cuenca

Abstract

Microplastic pollution poses a growing threat to aquatic ecosystems both nationally and globally. This study focused on the quantification and classification of microplastics in the Machángara River, one of the main water bodies in the city of Cuenca, Ecuador. This river is especially important because its upper section provides water for human consumption, while its lower section is used for agricultural, industrial, and other anthropogenic purposes. Five strategic sampling points were established along the river: 1) Chanlud Dam, 2) Rural Area Start, 3) Industrial Park Start, 4) Industrial Park End, 5) Confluence with the Tomebamba River. The sample collection followed the Ecuadorian Technical Standard NTE INEN 2176:2013, using composite sampling techniques to ensure representativeness. The samples were then processed and analyzed in the laboratory of the Center for Environmental Studies (CEA) using a stereomicroscope to classify microplastics by shape (fragments, fibers, spheres, films, and sponges), size, and concentration. Results showed a high presence of microplastics, with a maximum concentration of 15,754 particles per liter (part/L), and significant variations across sampling points and weeks, with increases in urban and industrial areas. Morphologically, the most common types of microplastics were fragments, sponges, and films, ranging in size from 0.24 µm to 4,410 µm. These findings confirm the presence of microplastics in the Machángara River, indicating potential risks for both environmental and human health. Therefore, it is essential to implement appropriate management strategies and promote awareness about the responsible use and disposal of plastics.