Evaluación de la contaminación por metales pesados mediante un análisis comparativo multindex en sedimentos: caso de estudio estuario la puntilla, Cantón el Guabo, Provincia del Oro

Abstract

This research aimed to evaluate the contamination by heavy metals in sediments through a comparative Multindex analysis in the estuary "La puntilla", located in the canton of El Guabo, Province of Oro, in southern Ecuador. Twenty-five sediment samples were collected at 11 sample points using a fishing boat, PVC pipe, and a single-body borehole. Using the Atomic Absorption Spectroscopy technique, the concentrations of Cadmium (Cd), Lead (Pb), Arsenic (As), Mercury (Hg) and Iron (Fe) were determined. A Pearson correlation analysis was carried out between the physical-chemical parameters of the sediment and heavy metals and an evaluation of the Enrichment Factor, Geoaccumulation index and Ecological Risk index. The results showed significant contamination of Arsenic and Mercury in the mangrove sediments, with a predominant anthropogenic source at points P6 and P7 of Zone 2. The Ecological Risk indices indicated a moderate level of risk in said area. It is recommended to carry out studies during the rainy season to compare the concentrations of metals in the same depths, providing additional information on contamination. This work provides a comprehensive view of heavy metal contamination in mangrove sediments, allowing the identification of higher-risk areas and guiding future environmental management actions.