Heavy element contents of vegetables and health-risk assessment in China

This study analyzed five heavy elements (HEs), including cadmium (Cd), chromium (Cr), mercury (Hg), lead (Pb), and arsenic (As), in fresh vegetables (i.e., legume, rhizome and potato, gourd, bulb, solanaceous fruit, leafy, and brassica; total: 7214) collected from 31 provinces in China from 2016 to the first half of 2017. By analyzing the concentration level of the five HEs in seven regions (the Northeast, North China, East China, South China, Central China, the Northwest, and the Southwest), except for As, average HEs concentrations were higher in the Southwest than that in the other six regions. According to the maximum permissible limit (MPL), the highest rate of HEs concentration above the MPL was found in the Southwest (11.038%). Analysis of variance (ANOVA) showed varying degrees of variability between regions and categories. By using principal component analysis (PCA), it was found that two principal components account for 73.79% of the total variance in the data. Together with hierarchical cluster analysis (HCA), concluded that Tibet was significantly different from the other 30 provinces. By calculating estimated daily intake (EDI) and the target hazard quotient (THQ), the EDI of Cr in the Southwest was the highest, with results of 1.2119 μg/kg/day for children and 0.8073 μg/kg/day for adults. North China had the highest total target hazard quotient (TTHQ) for HEs in vegetables ingested by children, with a result of 0.933.