Levels of eight heavy metals and health risk assessment considering food consumption by China's residents based on the 5th China total diet study

The total diet study (TDS) is a significant part of food consumption-based health risk assessment. Since 1990, China has conducted five TDSs based on its unique food culture. In the present study, the health risks of residents from 20 regions of China are assessed by comparing the estimated daily intake (EDI) with adequate intake (AI) for Cr, and the estimated dietary exposure (EDE) with the reference dose (RfD) for seven toxic heavy metals (THMs), which are Al, As, inorganic arsenic (iAs), Cd, Hg, methyl mercury (MeHg), and Pb. The original data were sourced from the 5th China TDS. The data indicated the following: (1) Cereals and vegetables were the main dietary exposure sources of Al, As, iAs, Cd, and Cr; aquatic foods were the important dietary exposure source for As, Hg, and MeHg, especially for the residents from coastal regions. (2) Compared to other elements, Pb had more dietary exposure sources, which included cereals, vegetables, meats, and beverages and water. (3) Potatoes, beverages and water, and meats were the important sources of Al, iAs, and Cr. The results showed that the average level of the dietary intake of Cr was 11 times higher than the AI, as determined from the ratio of EDI to Al. Moreover, the hazard quotients (HQs) of Al, iAs, Cd, Hg, MeHg, and Pb were1, while that of As (6.49) was1; therefore, the EDIs of As and Cr by the residents of China are worthy of attention. Additionally, the discrepancies in the dietary exposures of HMs by the residents were due to the different HM contents among different types of foods, and the different dietary structures.