ABSTRACT
Toxic and hazardous metals such as cadmium (Cd) and Lead (Pb) can cause cancer in humans; hence, reducing their bioavailability in the soil is crucial for human health and environmental safety. In this study, biochar modified with nanoscale zero-valent iron (nZVI-BC) was synthesized from low-cost adsorbent waste materials and iron (iii) oxide (Fe2O3) via carbothermal reduction process for stabilization of Pb and Cd in the soil. Furthermore, an evaluation of treatment efficiency on exposure health hazards for both carcinogenic and non-carcinogenic risks was done. The results revealed that nZVI-modified eggshell biochar was able to reduce the concentration bioavailable of Pb and Cd in soil by (69–75%) and (62–65%), and reduce the toxicity leaching of Pb and Cd by (53–66%) and (68–75%), respectively. The treatments reduced carcinogenic risk (CR) and hazard index (HI) in children and adults by 35–47% for Pb and 25–36% for Cd, respectively. Hence, this study proposes a new way to reduce and modify environmental wastes to make nZVI-supported biochar that can remediate toxic metals from the soil, improve soil nutrients, reduce human exposure health risks, and enhance the environment’s health.
Disclosure statement
No potential conflict of interest was reported by the author(s).
Data availability statement
Research data are available only by the corresponding author based on reasonable request.
Authorship contribution statement
Moses Akintayo Aborisade: Conceptualization, methodology, investigation, data curation, analysis, original draft writing, and review. Aixi Feng: Resources. Belay Tafa Oba and Akash Kumar: Review writing, editing, and data curation. Ashenafi Yohanes Battamo: Visualization and validation. Menglu Huang and Chen Daying: Resources and software. Yongkui Yang and Peizhe Sun: Methodology and resources. Lin Zhao: Administration, funding, resources, and supervision.