A review of research progress on prevention and control technologies for arsenic and cadmium composite pollution in paddy soil†

Arsenic (As) and cadmium (Cd) are among the most common potentially toxic elements (PTEs) found in paddy soil, where they can easily transfer from soil to rice grains. The widespread contamination of paddy soil with As and Cd, either individually or in combination, poses a significant threat to food security and human health in China. As and Cd exhibit different behaviours in soil, making the simultaneous management of As–Cd composite pollution a major technical challenge for safe rice production. This review summarizes several practical techniques for synchronously controlling uptake and translocation of As and Cd in rice plants, including water management, soil passivation, leaching technology, electrokinetic remediation, phytoremediation, selection of low-accumulation rice varieties, and application of foliar inhibitors. The treatment effects, mechanisms, and constraints of each technique are analyzed, and the development directions of the main control technologies are proposed. It emphasizes the importance of developing regionally adaptive, comprehensive technology models to manage paddy soil co-contaminated with Cd and As and ensure the safe production of rice.