Assessment of cadmium toxicity in buffaloes grazing on forages cultivated in diverse irrigated soils: a comprehensive analysis

This study investigated the potential risks of cadmium (Cd) toxicity in buffaloes grazing on forages that were cultivated in soils irrigated by various sources of wastewater. The absorption of trace metals (TM) by plants and their subsequent entry into the food chain pose a significant danger to grazing animals through the accumulation of contaminated fodder. The mean concentration of Cd in the water ranged from 0.18–1.78 mg/L, in the soil 0.63 to 1.87 mg/kg, in the forage 0.20 to 1.32 mg/kg, and in the blood 0.26 to 1.98 mg/L. Among all three sites, canal water (CW Site I), groundwater (GW Site II), and sewage water (SW Site III), the concentration factor (CF) values were below the threshold of 1 (CF < 1), indicating the nominal environmental concern regarding Cd contents in the soil-plant interface. In addition, a prominent variation was noticed in the transfer factor (TF) of Cd across different sites, with the highest TF observed in Avena sativa L. at SW Site III (0.8) and the lowest in Pennisetum glaucum L. at CW Site I (0.27). Furthermore, the hazard quotient (HQ) exhibited a substantial fluctuation, ranging from 0.39 to 2.6, reflecting varying levels of potential health risks associated with Cd exposure. The outcomes of the current investigation suggested that the prominent increase in Cd levels was recorded at sampling site SW Site III due to continuous wastewater irrigation. Prolonged exposure and increased Cd absorption in buffaloes grazing at these sites could have harmful long-term effects on their health. The correlation analysis between Cd concentrations in water, soil, forage, and blood showed a positive but non-significant relationship for water-soil, soil-forage, and forage-blood interactions. This highlights the need for further research to assess the long-term implications of wastewater irrigation on heavy metal accumulation in livestock.