Concentration of Heavy Metals in Surface Water and Sediments in the Middle Lower Ctalamochita River Basin, Córdoba, Argentina: Geoaccumulation Index and Human Health Risk Assessment

MICHELLE BIOLÉ; NOELIA URSELER; JULIETA GRIBOFF; ROMINA BACHETTI; CAROLINA MORGANTE; MAGDALENA MONFERRAN

Montevideo

Congreso; SETAC Latin America 15th Biennial Meeting; 2023

SETAC Latin America

Surface water is one of the most important resources in Córdoba province (Argentina) and receives a complex mixture of natural and anthropogenic contaminants. This study aimed to analyze theconcentrations of As, Cd, Cr, Hg and Pb in surface water and sediments in the middle-lower basinCtalamochita river basin, Córdoba; estimate the geoaccumulation index of elements in sediments; and assess the human health risk associated with water consumption. Water and sediment samples were collected at 14 sites in the Ctalamochita river during November 2021 and elements concentrations were determined by inductively coupled plasma-mass spectrometry. The geoaccumulation index (Igeo) of elements in sediments was estimated. The non-carcinogenic human health risk related to water consumption was assessed by estimating the hazard quotient (HQ) and hazard index (HI). The elements with the highest concentrations were Pb and As in surface water (6.78 to 14.7 μg/L and 1.65 to 38.8 μg/L, respectively) and Pb, Cr and As in sediments (0.73 to 13.2 μg/g; 0.28 to 1.57 μg/g and 0.16 to 3.20 μg/g, respectively). The Igeo showed high pollution levels for Cr and Pb classifying from "heavily polluted" to "extreme pollution" at monitoring sites. As presented the greatest variability ranging from "unpolluted" to "heavily polluted". Both, Cd and Hg, showed Igeo values lower than 0 in all sites indicating "non-polluted" sediments. The HQ and HI indices, for all elements and sites (except for HQAs in three sites and HI in four sites) suggest no risk for the population (HQ and HI < 1). Specifically, HQAs was 1.53 in Bell Ville city, 2.28for Bell Ville rural drainage channel and 4.58 for San Marcos Sud town. The HI (total risk) was higher than 1 in Morrison town and in the sites mentioned above, suggesting a non-carcinogenic risk for the water consumption for the general population. At sites where HI was higher than 1, the major HQ index contributors was As. This study area is one of the largest regions in the world with high As concentrations in groundwater, however this metalloid may occur in surface water as a consequence of both natural contamination and anthropogenic activities. The assessment of risks consumption associated with levels of heavy metals in surface water of Córdoba is essential for the agencies that control hydric resources and health surveillance to develop guidelines on safe consumption, strategies for removal methods, and implementation of long-term monitoring programs.