Sustainable risk management of heavy metal contaminated agricultural soil: Current frameworks and future perspectives

Heavy metal (HM) contamination in agricultural soils poses a growing threat to sustainable agriculture, food safety, and human health. Risk Management Frameworks (RMFs) have been widely adopted to regulate HM contamination, but their effectiveness and adaptability vary across countries due to differences in institutional design, technical guidance, and regulatory implementation. Moreover, the limited sustainability and structural shortcomings of the RMFs remain significant obstacles to achieving the United Nations Sustainable Development Goals. Therefore, this study first examines HM behavior and environmental risks in agricultural soil, followed by a retrospective of major global soil HM pollution cases and policy responses. We then systematically review the development, structure, and critical components of RMFs in four developed countries. These include the United States, United Kingdom, Netherlands, and Canada, chosen for their early legislative action and leadership in soil risk governance. Specifically, comparative policy review and structural framework analysis are employed to examine Theoretical foundations, policy instruments, regulatory mechanisms, and risk models across selected countries. The findings reveal that these RMFs typically integrate soil legislation, risk criteria, technical guidelines, and regulatory mechanisms. Despite proven effectiveness in monitoring, risk quantification, and remediation, current RMFs remain constrained by several limitations. These include insufficient source prevention, weak adaptability to complex pollution scenarios, and inadequate consideration of soil health conservation. In response, we propose that future RMFs should prioritize source-oriented, full-chain risk control; incorporate multi-pollutant, sustainable practices; and adopt AI-driven, dynamically updated mechanisms to enhance long-term sustainability and ecosystem resilience. These findings provide practical guidance for enhancing RMFs in developing countries, helping to establish systematical, context-sensitive, sustainable frameworks for managing soil heavy metal contamination.