SBRC体外模拟法对含砷矿物生物可给性的研究

Bioaccessibility of Arsenic Bearing Minerals Using in vitro Extraction Method of SBRC

粉尘中的砷通过口部无意食入是进入人体的3种摄入途径之一,摄入的砷会危害人体健康。目前研究表明,体外模拟方法测定生物可给性可用来代替动物实验来研究生物有效性。该研究以4种砷污染矿物(赤铁矿、磁铁矿、高岭土、蒙脱石)为研究对象,选用SBRC体外胃肠液模拟方法,研究分析模拟胃肠相条件参数及食物营养元素和成分对砷生物可给性影响。结果表明,随着模拟胃相pH值或固液比的增加,4种矿物的砷生物可给性有下降的趋势;模拟胃相反应时间的增加,砷的生物可给性缓慢增加;进入模拟肠相后,砷的生物可给性均有不同程度的下降;随着反应时间的增加有所提高,模拟肠相pH增加后,砷的生物可给性先增加后减小。在添加抗坏血酸后,砷生物可给性在模拟胃相和肠相中均增大;在添加锰盐、铁盐或铝盐后,模拟肠相中砷的生物可给性有显著的减小,其中添加铁盐在模拟胃相时也有一定的减小,而添加锰盐和铝盐后,模拟胃相的砷生物可给性变化不大。

Ingestion is one of the three pathways that arsenic in the dust assimilates through the mouth by incidental intake.Bioaccessibility is one of important evaluation methods for the risk of arsenic contaminated soil to human. And the method of in vitro digestion has been used to access the bioaccessibility of arsenic in dust from contaminated soils. Four typical contaminated soils, including hematite, magnetite, kaolinite and montmorillonite were estimated using the method of SBRC(solubility bioavailability research consortium). The effects of simulated gastrointestinal parameters and food nutrition on arsenic bioaccessibility were studied. The results demonstrated that arsenic bioaccessibility tended to decrease with the gastro fluid pH and the ratio of soil to fluid in gastro phase increasing. Arsenic bioaccessibility tended to increase slowly with reaction time of gastro phase. Arsenic bioaccessibility had a different degree of decline when intestinal phase started. With the value of intestinal phase increasing, arsenic bioaccessibility increased firstly and then decreased. After adding manganese salt, iron salt, or aluminum salt, arsenic bioaccessibility decreased significantly in intestinal phase. In gastro phase, arsenic bioaccessibility decreased with adding iron salt and it had no significant change with adding manganese salt or aluminum salt. With adding ascorbic acid,arsenic bioaccessibility increased in gastro/intestinal phase.