<p>The contamination of agricultural soils by heavy metals (Cd, Cr, Ni, Zn, Cu, Co, and Pb) due to untreated wastewater irrigation poses a significant threat to environmental quality and food safety. Biochar as a soil amendment is used to reduce the heavy metal uptake from soil to plants. Simple biochar (SB) refers to unaltered biochar produced through pyrolysis of biomass without any additional treatment. Modified biochar, on the other hand, is biochar that has been chemically treated with potassium permanganate (KMnO₄) to enhance its surface properties and metal-binding capacity. The research investigates how both forms of biochar influence heavy metal immobilization in soil and limit their uptake by plants. The highest reduction in heavy metal availability was achieved by the modified biochar, with the reductions of 79, 70, 75, 60, 66, 58, and 56% for Cd, Zn, Ni, Co, Cr, Pb, and Cu, respectively. Additionally, the biochar amendments reduced the levels of toxic heavy metals in the edible parts of beetroot, bringing them below the safe limits. Biolog EcoPlate analysis showed that modified biochar significantly enhanced microbial diversity. The simple and modified biochar also led to an increase in the biomass of beetroot plants, with the greatest biomass observed at 15 t/ha of modified biochar. Moreover, the concentration of Cd, Zn, Ni, Co, Cr, Pb, and Cu in the root and shoot of the plants were significantly reduced with biochar treatments. The high-resolution mass spectrometry (HR-MS) analysis detected a significant level of Pantothenic acid, Pyridoxal, and Betalain in beetroot plants amended with modified biochar. The Principal component analysis biplot shows that biochar, especially modified biochar, enhanced microbial activity and nutrient availability while reducing heavy metal uptake in plants. This strategy could be a sustainable approach for reducing food chain contamination and for providing quality food products.</p>