Bioaccessibility of Cadmium in Common Vegetables in Typical Environmental High Cadmium Region and the Health Risk Assessment

In order to assess the health risk of consumption of local planted vegetables in high-level Cd contaminated region, inductively coupled plasma mass spectrometry (ICP-MS) was employed to determine the elements of Cd, Mg, K, Ca, Cu and Zn in the commonly consumed vegetables collected from this region. The effects of the cooking methods, the process of gastrointestinal digestion, and the concentrations of elements on the bioaccessibility of Cd were investigated using in vitro RIVM model. In addition, the health risk of Cd exposure via vegetable consumption for the local residents were evaluated using the target hazard quotients (THQs). The results showed that the average contents of Cd in vegetables were ranged from 0.02 to 0.30 mg/kg. Cooking methods did influence the concentration of Cd in the samples, indicating that boiling significantly reduced the concentration of Cd in vegetables (P<0.05), while frying had no significant effect (P>0.05). In contrast, boiling significantly increased the bioaccessibility of Cd (P<0.05), and frying had no significance (P>0.05). The results of correlation analysis showed that Cd bioaccessibility had significantly negative correlation with K and Cu (P<0.05), indicating that mineral elements in vegetables could influence on the bioaccessibility of Cd in vegetables. The results of health risk assessment showed that only the THQ of sub-population of highly consumed with lettuce higher than 1 when the Cd bioaccessibility was considered in the process of health risk assessment, suggesting that the health risk of local residents was low with consumption of local planted vegetables. However, the chronic hazards of Cd exposure should be highly concerned on other dietary sources in this high-level Cd region. Therefore, local residents should choose the vegetables lower than the maximum limit values with appropriate cooking to reduce health risk.