Comparative effects of biochar-nanosheets and conventional organic-amendments on health risks abatement of potentially toxic elements via consumption of wheat grown on industrially contaminated-soil.

Potentially toxic elements (PTEs) discharge to the soil environment through increased anthropogenic activities is a global threat. These PTEs can have harmful and chronic-persistent health effects on exposed populations through food consumption grown on contaminated soils. Efforts to investigate the transformation mechanism and accumulation behavior of PTEs in soil-plant system and their adverse health-effects have focused extensively in previous studies. However, limited studies address biochar nanosheets (BCNs) as a potential soil amendment to reduced humans health risks through dietary intake of food-crop grown on PTE-contaminated soil. Here, we showed how BCNs cutback health hazards of PTEs through impacts on bioavailability and phytoaccumulation of PTEs, and their daily intake via consumption of wheat. When BCNs amendment was compared with both conventional organic amendments (COAs) and control, it significantly (P ≤ 0.05) reduced bioavailability and uptake of PTEs by wheat plants. Based on risk assessment results, the hazard indices (HIs) for PTEs in all treatments were <1, however, BCNs addition significantly (P ≤ 0.05) reduced risk level, when compared to control. Furthermore, the cancer risks for Cd, Cr and Ni over a lifetime of exposure were higher in all treatments than the tolerable limit (1.00E-4 to 1.00E-6), however BCNs addition significantly suppressed cancer risk compared to control. Conclusively, our results suggest that BCNs can be used as soil amendment to reduce potential risks of PTEs through consumption of food grown in PTE-contaminated soils.