Geochemical characterization of heavy metals in the soil rice system and risk assessment for human health

The ingestion of heavy metals in agricultural soils by the population has implications for human health. The research demonstrate that the concentration of Cd in the soil exceeded the national background level, with 62% of soil samples surpassing the Chinese soil screening value. Furthermore, 42% of the analyzed rice grains exhibited Cd levels that surpassed the established standard. Notably, there was no significant association between the concentration of Cd in soil and rice. The bio-effectiveness of heavy metals was enhanced in soils with low pH, and residue state was the main storage form for heavy metals. Cd exhibited a different distribution pattern compared to other heavy metals. Human health risk assessment revealed that children in the study area were at greater risk, particularly due to non-carcinogenic and carcinogenic effects of Cd. These findings provide valuable insights for the development of strategies to remediate heavy metal contamination in similar areas..