Risk assessment of rare earth elements in fruits and vegetables from mining areas in China

Assessment of contaminated food through the dietary intake is essential for human health. To investigate the health risk of rare earth element (REE) exposure to fruits and vegetables in mining areas in China, we collected 288 fruit samples and 942 vegetable samples from four representative mining points (Bayan Obo in Inner Mongolia, Weishan in Shandong, Maoming in Guangdong, Longnan in Jiangxi) and their control areas. The content of REEs was determined by inductively coupled plasma-mass spectrometry (ICP-MS). The total REEs in fruits from mining and control areas were 12.90 μg kg^-1 and 11.89 μg kg^-1, and in vegetables were 92.90 μg kg^-1 and 62.38 μg kg^-1, and the difference was statistically significant in vegetables (P = 0.048). The drupes had more REE concentration in fruits (68.41 μg kg^-1, 16.90 μg kg^-1 in mining and control areas, respectively) (P < 0.01), and the leafy vegetables had more REE concentration in vegetables (245.81 μg kg^-1, 123.51 μg kg^-1 in mining and control areas, respectively) (P < 0.01). With the enrichment of light rare earth elements (LREE), the REE distribution patterns coincided in mining and control areas and different types of fruits and vegetables. The health risk assessment indicated that the estimated daily intakes (0.02-0.06 μg kg^-1 day^-1, 0.53-1.22 μg kg^-1 day^-1 for fruits and vegetables, respectively) were lower than the allowable daily intake value (60.4 μg kg^-1 day^-1). In mining areas, REEs obtained from fruits and vegetables were insufficient to cause health damage to human beings. However, sustained exposure to low REEs, especially for children, still needs attention.