污染土壤中氟的人体胃肠吸收可给性影响因素及健康风险

Influence factors controlling fluorine bioaccessibility in contaminated soils and corresponding health risks

于太原某氟污染场地采集16个土壤样品,通过体外模拟(in vitro)胃肠消化的方法,利用配制的模拟胃、肠液提取土壤中氟,研究其人体可给性,并分析人体可给性对风险评估结果的影响.结果显示,土壤中氟在胃、肠提取阶段的可给性分别为2.59%~6.57%和1.09%~2.52%,平均值分别为3.53%和1.44%.胃提取阶段氟的人体可给性浓度与土壤水溶性氟含量(P<0.01,n=16)、TFe(P<0.01,n=16)和TAl(P<0.01,n=16)呈显著正相关,肠提取阶段氟的人体可给性浓度与胃阶段氟的可给浓度(P<0.01,n=16)呈显著正相关.基于土壤水溶性氟和总铝含量能较好地预测氟在胃阶段的人体可给性浓度,基于氟在胃提取阶段的人体可给性浓度能较好地预测其在肠提取阶段的人体可给性浓度,模型相关系数(R^(2))分别为0.96和0.98.以土壤样品中总氟浓度为暴露浓度计算的健康风险分别是考虑氟在胃及肠提取阶段人体可给性的15.23~37.01倍和39.76~86.67倍.

Fluorine(F)bioaccessibility of 16 soil samples from a contaminated site of Taiyuan was measured using the method of in vitro of gastrointestinal digestion,and the influence of F bioaccessibility on its risk assessment was evaluated.The results revealed that F bioaccessibility in the stomach and intestine were between 2.59%~6.57%and 1.09~2.52,with the average value of 3.53%and 1.44%,respectively.F bioaccessible concentration in stomach was positive correlated with water soluble F(c_(s)')(P<0.01,n=16),total Fe(TFe)(P<0.01,n=16)and total Al(TAl)(P<0.01,n=16)in soils,while F bioaccessible concentration in intestine was positive correlated with that in stomach(P<0.01,n=16).A model regressed based on c_(s)'and TAl in the soil could predict F bioaccessibility in the stomach very well with R^(2) being 0.96,and the bioaccessibility in the intestine could be predicted precisely using a regression model based on that in the stomach with R^(2) being 0.98.The health risk calculated based on F concentration in the soils was 15.23~37.01times and 39.76~86.67 times the values when the bioaccessibility in the stomach and intestine were considered in calculation.