Environmental cadmium pollution and health risk assessment in rice-wheat rotation area around a smelter

Cadmium (Cd) pollution induced by smelting process is of great concern worldwide. However, the comprehensive risk assessment of Cd exposures in smelting areas with farming coexist is lacking. In this study, atmospheric deposition, soil, surface and drinking water, rice, wheat, vegetable, fish, pork, and human hair samples were collected in rice-wheat rotation area near nonferrous smelter to investigate smelting effect on environmental Cd pollution and human health. Results showed high Cd deposition (0.88-2.61 mg m^-2 year^-1) combined with high bioavailability (37-42% totality) in study area. Moreover, 90%, 83%, 57%, and 3% of sampled soil, wheat, rice, and vegetable of Cd were higher than national allowable limits of China, respectively, indicating smelting induced serious environmental Cd pollution. Especially, higher Cd accumulation occurred in wheat compared to rice by factors of 1.5-2.0. However, as for Cd exposure to local residents, due to rice as staple food, rice intake ranked as main route and accounted for 49-53% of total intake, followed by wheat and vegetable. Cd exposure showed high potential noncarcinogenic risks with hazard quotient (HQ) of 0.63-4.99 using Monte Carlo probabilistic simulation, mainly from crop food consumption (mean 94% totality). Further, residents' hair Cd was significant correlated with HQ of wheat and rice ingestion, highlighting negative impact of cereal pollution to resident health. Therefore, smelting process should not coexist with cereal cultivating.