Evaluación espacio-temporal de elementos potencialmente tóxicos en cuerpos de agua superficial en Santa Rosa, Ecuador

Abstract

CONDITION FOR PUBLICATION OF PROJECT. Mining is a crucial component of the global economy, providing vital resources for sectors such as construction, energy, and electronics. However, this activity also has significant impacts on the environment and human health. This study examined the presence of potentially toxic elements (PTEs) in water bodies within the Santa Rosa mining area, aiming to assess their spatial and temporal variations and the health risks for people engaging in recreational activities in these rivers. Surface water samples were collected from the Santa Rosa River and from the Los Gringos and El Panteón streams during both the dry (DS) and rainy (RS) seasons. Physicochemical parameters were measured directly in the field, while PTE concentrations (Al, As, Cd, Co, Cu, Fe, Mn, and Zn) were determined using inductively coupled plasma mass spectrometry (ICP-MS). The data were analyzed statistically to identify correlations and significant trends, and the spatial and temporal distribution of contaminants was mapped with geographic information systems (GIS). Human health risks were estimated using the non-carcinogenic hazard index (HI) and the carcinogenic risk (CR). Results indicated that streams near areas of intensive mining activity, especially Los Gringos and El Panteón, showed high concentrations of Al, Cd, Cu, Mn, and Zn, often exceeding limits set by Ecuadorian regulations. In terms of public health, arsenic (As) was identified as the most concerning contaminant, with CR values exceeding acceptable thresholds for both adults and children, primarily due to accidental water ingestion during recreational activities. Keywords: water quality, health risk assessment, mining industry, environmental impact.