Silica sources for arsenic mitigation in rice: machine learning-based predictive modeling and risk assessment

Arsenic (As) is a well-known human carcinogen, and the consumption of rice is the main pathway for the South Asian people. The study evaluated the impact of the amendments involving CaSiO3, SiO2 nanoparticles, silica solubilizing bacteria (SSB), and rice straw compost (RSC) on mitigation of As toxicity in rice. The translocation of As from soil to cooked rice was tracked, and the results showed that RSC and its combination with SSB were the most effective in reducing As loading in rice grain by 53.2%. To determine the risk of dietary exposure to As, the average daily intake (ADI), hazard quotient (HQ), and incremental lifetime cancer risk (ILCR) were computed. The study observed that the ADI was reduced to one-third (0.24 mu g kg(-1)bw) under RSC+SSB treatments compared to the control. An effective prediction model was established using random forest model and described the accumulation of As by rice grains depend on bioavailable As, P, and Fe which explained 48.5, 5.07%, and 2.6% of the variation in the grain As, respectively. The model anticipates that to produce As benign rice grain, soil should have P and Fe concentration more than 30 mg kg(-1) and 12 mg kg(-1), respectively if soil As surpasses 2.5 mg kg(-1).

Automated summary

Arsenic is a well-known carcinogen, and rice consumption is the main pathway of exposure for people in South Asia. This study evaluated the effectiveness of different amendments in reducing arsenic toxicity in rice. The results showed that rice straw compost combined with silica solubilizing bacteria was the most effective in reducing arsenic content in rice grains. The study also developed a prediction model to determine the accumulation of arsenic in rice grains, providing guidance for producing arsenic-free rice.