Biochars Affect the Mobility of Carcinogenic Polycyclic Aromatic Hydrocarbons (PAHs) in Amended Soil and Their Bioaccumulation in Spinach

The long-term persistence of potentially carcinogenic pollutants, like polycyclic aromatic hydrocarbons (PAHs), in agricultural soil has attracted the world scientists for using various biochars to assess their applicability for reducing their mobility in soils and bioaccumulation in food crops. Experiments were conducted to check the influence of different biochars, like rice straw biochar (RSBC), sewage sludge biochar (SSBC), and soybean stalk biochar (SBBC), on polycyclic aromatic hydrocarbons mobility and bioaccumulation in spinach added at the rates of 2, 5, and 10% to polluted soil. The application of selected biochars reduced the mobility of PAHs; however, the results were more effective at a rate of 5%. The application of biochar considerably ( P ≤ 0.05) minimized the bioaccumulation of PAHs in spinach, with decreases observed as 41–72% for RSBC, 15–37% for SSBC, and 38–69% for SBBC. The efficiency of RSBC in decreasing PAHs was more significant ( P ≤ 0.05) at rates of 2% and 5% compared to SBBC and SSBC. These findings suggest that RSBC treatment will be more effective for remediating PAHs from the contaminated soils.