锡矿山矿区食物中的锑污染及生物可给性研究

在湖南锡矿山锑矿区采集蔬菜类、主食类、肉类、蛋类等9种食物. 结果表明蔬菜类Sb浓度平均值为9.67 mg·kg^-1,主食类及肉类的Sb含量较低,平均浓度分别为0.025 mg·kg^-1和0.40 mg·kg^-1. 胃肠模拟法测得的Sb生物可给性为9.0%~57.7%,其中蔬菜中Sb生物可给性显著低于主食类及肉类. 生物可给性与食物中Fe含量呈显著负相关(r=-0.75,p=0.02),还与食物的植酸、草酸含量呈显著负相关(r=-0.95,p=0.01;r=-0.77,p=0.016). 根据锡矿山周边居民各类膳食的摄入量进行健康风险评估,以食物中的Sb总浓度计算暴露风险时,居民每日经由食物摄入的Sb总量达10227.01 ng·kg^-1·d^-1,经生物可给性矫正后下降为1807.02 ng·kg^-1·d^-1,但仍高于USEPA建议的400 ng·kg^-1·d^-1的参考剂量. 说明矿区经由Sb污染食物暴露依然存在健康风险,且考虑生物可给性对准确评价暴露风险至关重要.

Contamination and bioaccessibility of antimony in food of Xikuangshan mining district

In this study, 9 kinds of food were collected from Xikuangshan in Hunan Province, including vegetables, staple food, and meat. The Sb concentrations in vegetables were averaging at 9.67 mg·kg^-1, higher than those in staple (0.027 mg·kg^-1) and meat (0.40 mg·kg^-1), respectively. In vitro gastrointestinal method (IVG) was adopted to measure Sb bioaccessibility in food. The in vitro bioaccessibility were 9.0%~57.7% with values for vegetables lower than those for staple and meat. Bioaccessibility was negatively correlated with Fe content (r=-0.75, p=0.02), and was negatively correlated with phytic acid and oxalic acid (r=-0.95, p=0.01; r=-0.77, p=0.016) in food. If using total Sb concentrations, Sb daily intake through food was up to 10227.01 ng·kg^-1·d^-1, and decreased to 1807.02 ng·kg^-1·d^-1 if considering the Sb bioaccessibility, but the value was still higher than the USEPA guideline of 400 ng·kg^-1·d^-1. This indicates that there is potential health risk through exposure to Sb contaminated food in this area, and it is important to consider bioaccessibility when assessing the health risk.