Spatial distribution of cadmium pollution in locally produced rice and human exposure risk assessment in Wenzhou City

ObjectiveThis study aimed to evaluate the health risks of cadmium exposure in the local rice of Wenzhou residents by analyzing the pollution level and spatial distribution of cadmium in locally produced Wenzhou rice.MethodsThe monitoring data of local rice in Wenzhou from 2016 to 2021 were collected， and the spatial distribution of the cadmium concentration of local rice was displayed visually by ARCGIS 10.2. The Ordinary Kriging interpolation analysis was used to analyze spatial interpolation. The cadmium exposure was estimated by combining the concentration of cadmium in local rice with food consumption data. The health risk was assessed using a simple distribution model.ResultsThe median of cadmium in 740 local rice samples was 0.069 mg/kg. The detection rate and over-limit rate were 95.68% and 11.49%， respectively. The areas with high cadmium concentrations in local rice were mainly distributed in the northwest of Lucheng City and the central area of Rui’an City. The average exposure and the exposure of high-consumption groups （P95） to cadmium through eating local rice in Wenzhou adult residents were 12.04 and 21.08 μg/kg·BW， respectively. The average and high-consumption group exposure to cadmium in children were 17.02 and 32.04 μg/kg·BW， respectively. The average exposure and the exposure of high-consumption groups to cadmium by eating local rice in Lucheng were greater than the provisional tolerable monthly intake （PTMI）.ConclusionThe cadmium exposure levels of 1.16% of all adult residents in Wenzhou by eating local rice were higher than the PTMI. Children with high rice consumption had a higher cadmium exposure level from local rice， and residents had a higher health risk of cadmium exposure by eating local rice in Lucheng.