利用in vitro方法研究不同铁矿对土壤砷生物可给性的影响  

Effect of Different Iron Minerals on Bioaccessibility of Soil Arsenic Using in vitro Methods

作　　者：钟松雄[1,2] 尹光彩[1] 黄润林[1] 何宏飞[1] 陈志良[2] 林亲铁[1] 王文科[1] ZHONG Song-xiong YIN Guang-cai HUANG Run-lin HE Hong-fei CHEN Zhi-liang LIN Qin-tie WANG Wen-ke(School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006, China South China Institute of Environmental Science, Ministry of Environmental Protection, Guangzhou 510665, China)

机构地区：[1]广东工业大学环境科学与工程学院,广州510006 [2]环境保护部华南环境科学研究所,广州510655

出　　处：《环境科学》2017年第3期1201-1208,共8页Environmental Science

基　　金：广东省教育部产学研结合项目(2012B091000152);广东省科技计划项目(2013B020700010);公益性科研院所基本科研业务费专项(pm-zx021-201410-023)

摘　　要：为了研究不同铁矿物对土壤砷生物可给性的影响,利用PBET(physiologically based extraction test)、SBRC(solubility bioaccessibility research consortium assay)和IVG(in vitro gastrointestinal extraction)这3种in vitro方法研究水铁矿、针铁矿和赤铁矿对土壤砷在胃与小肠阶段生物可给性的影响以及砷形态转化对砷的生物可给性影响机制.结果表明,添加1%水铁矿时,根据PBET、SBRC和IVG这3种in vitro方法,胃阶段砷的生物可给性分别为2.22%、5.11%和7.43%,小肠阶段砷的生物可给性分别为3.39%、2.33%和6.18%;当投加量提高到2%时,各阶段砷的生物可给性都显著降低(P<0.05).3种in vitro方法,在不同铁矿物投加量相同条件下,相比于空白对照组(CK),砷的生物可给性降低幅度大小依次为:水铁矿(F1)>针铁矿(G1)>赤铁矿(H1)(F2>G2>H2).3种in vitro方法中可交换态和专属吸附态砷总量(F1+F2)同胃阶段砷的生物可给性呈正相关性,依据PBET、SBRC和IVG法,相关系数分别为r=0.93,P=0.002、r=0.90,P=0.004和r=0.89,P=0.006;F1+F2同小肠阶段砷的生物可给性呈正相关性,PBET和IVG法的相关系数分别为r=0.94,P=0.001和r=0.87,P=0.009,而SBRC法则表现为没有相关性.同样,3种in vitro方法中都表现出无定型铁结合态砷(F3)与胃阶段砷的生物可给性有显著负相关性,而与小肠阶段砷生物可给性则除了SBRC法没有相关性之外,PBET和IVG法都表现出显著负相关性.To explore the effects of different iron minerals on soil arsenic bioaccessibility,ferrihydrite,goethite and hematite were used in PBET,SBRC and IVG in-vitro experiments in this study. The relationship between arsenic bioavailability in gastric,small intestinal phases and arsenic speciation was also studied. The results showed that when 1% ferrihydrite was added,arsenic bioavailability in gastric phase was 2. 22%,5. 11% and 7. 43% by PBET,SBRC and IVG methods,respectively,while in the small intestinal phase it was 3. 39%,2. 33% and 6. 18%. At an elevated ferrihydrite dosage of 2%,significant difference in arsenic bioavailability was observed in both phases（ P 〈 0. 05）. According to in vitro experiments,the addition of the same amount of different iron minerals had contributed to the decrease in arsenic bioavailability to varying extents in contrast with the blank group,in the descending order of ferrihydrite（ F1） 〉 goethite（ G1） 〉 hematite（ H1）（ F2 〉 G2 〉 H2）. Total arsenic in exchangeable（ F1） and specifically sorbed（ F2）state was found positively correlated with arsenic bioavailability in gastric phase by PBET,SBRC and IVG methods,the correlation coefficient of which being r = 0. 93,P = 0. 002,r = 0. 90,P = 0. 004 and r = 0. 89,P = 0. 006,respectively. It was also found that arsenic bioavailability in gastric phase was positively correlated with total arsenic in F1 and F2 states by PBET（ r = 0. 94,P = 0. 001）and IVG（ r = 0. 87,P = 0. 009） methods,but no significant correlation was observed by SBRC method. Additionally,three in vitro experiments showed that amorphous iron bound arsenic had significant negative correlation with arsenic bioavailability in gastric phase and small intestinal phase,except that no correlation was found in small intestinal phase by SBRC method.

关 键 词：生物可给性 in VITRO 铁矿物 砷 稳定化 

分 类 号：S153.61[农业科学—土壤学]