An Assessment of Dietary Exposure to Cadmium in Residents of Guangzhou, China

Cadmium and its compounds are human carcinogens with severe organ toxicity, and their contamination of agricultural soil in China has been frequently reported: however, the dietary exposure to cadmium in residents and the relevant health risk have seldom been reported. In this study, the concentration of cadmium in various types of food collected from 2013 to 2015 were analyzed using graphite furnace atomic absorption spectrometry, and the dietary exposure to cadmium assessed based on a dietary survey in 2976 Guangzhou residents. In total, 3074 out of 4039 food samples had cadmium levels above the limit of detection. The mean ± standard deviation (50th, 95th percentile) cadmium content in all samples was 159.0 ± 112.7 (8.6, 392.4) μg/kg, with levels ranging from 1.0 to 7830 μg/kg. Using the mean cadmium concentrations, the average monthly dietary exposure of Guangzhou residents to cadmium was 14.4 (μg/kg body weight (BW), accounting for 57.6% of the provisional tolerable monthly intake (PTMI). Rice, laver, vegetables, and live aquatic products were the main sources of cadmium intake, on average accounting for 89% of the total value. The dietary cadmium exposure in high consumers (95th percentile food consumption) was 41.0 μg/kg·BW/month, accounting for 163% of the PTMI. Additionally, dietary cadmium exposure at mean consumption but high cadmium food concentration (95th percentile) was 32.3 μg/kg·BW/month, corresponding to 129% of the PTMI. The level of dietary exposure to cadmium in most Guangzhou residents was within the safety limit, thus increased health risk from dietary cadmium exposure is low at present. However, continued efforts by local governments to monitor the levels of cadmium in the four main food categories contributing to exposure are necessary.