Heavy Metals in Bioenergy Crop Production, Biomass Quality, and Biorefinery: Global Impacts and Sustainable Management Strategies

Heavy metals (HMs) including cadmium (Cd), lead (Pb), arsenic (As), zinc (Zn), copper (Cu), chromium (Cr), and nickel (Ni) pose significant challenges to bioenergy crop production due to their persistence, toxicity, and bioaccumulation in soils and plants. This study not only summarizes the mechanisms of HM absorption, translocation, and accumulation in bioenergy crops, but also critically assesses their impact on crop development, biomass quality, and biorefinery processes. Heavy metals disrupt key physiological processes and modify lignocellulosic composition, which is important for biofuel and biogas production. Global soil contamination from sources like industrial emissions, mining, and agricultural activities exacerbates these problems, posing a threat to both energy security and environmental sustainability. Sustainable management strategies, including phytoremediation, microbial bioremediation, soil amendments, and genetic engineering, are explored to mitigate HM effects while enhancing crop resilience. This review emphasizes the importance of integrating techniques to balance bioenergy production with environmental and human health and safety, including the use of HM-tolerant crop varieties, enhanced biorefinery processes, and robust policy frameworks. Future research should focus on developing scalable remediation technologies and interdisciplinary solutions that align with the United Nations’ Sustainable Development Goals and meet global bioenergy needs.