Quantitative study on reducing arsenic concentration in rice by sulfur fertilizer based on meta-analysis

Arsenic (As), a toxic metalloid, is absorbed by rice and subsequently enters the human body through the food chain. Sulfur (S) possesses the capacity to reduce As accumulation in rice tissues and has been widely researched for its contributions to enhancing soil quality. However, a clear quantitative consensus regarding the impact of S application on As bioaccumulation and bioavailability has yet to be established. To gain a more nuanced understanding of the interaction between S and As, a comprehensive analysis was conducted on 318 data sets extracted from 23 articles. Both meta-regression and subgroup analyses were employed to investigate the effect of diverse variables on As accumulation in rice. The results indicated that S had a significant dose-dependent effect on reducing As accumulation in rice. The exogenous S significantly reduced the As concentration in rice by 8.95% and the optimal S/As ratio for inhibiting As accumulation was 1-20. Apart from sulfate S, the incorporation of elemental S, persulfate, thiosulfate, and gypsum has been demonstrated to significantly reduce As accumulation in rice. The exogenous S resulted in a significant reduction in TF_{root to shoot} content in rice, indicating that S application may impede the physiological process of As transfer from soil to the shoot of rice. Consequently, the exogenous S can effectively mitigate the As accumulation in rice, thereby offering a novel approach to reduce the As content in rice and minimize its detrimental impact on human health.