食物粒径与混合方式对多溴联苯醚生物有效性的影响

Effect of Food Particle Size and Mixed Methods on the Bioaccessibility of Polybrominated Diphenyl Ethers

多溴联苯醚（PBDEs）是一类典型的持久性有机污染物（POPs）,口服摄入是其主要人体暴露途径。口服生物有效性是污染物健康风险评估中的关键因子。论文采用体外方法模拟食物在人体肠道中的消化过程,研究了食物粒径大小以及食物污染与混合方式对PBDEs生物有效性的影响。在〈150、150～212、212～250和〉250μm四个粒径范围的胡萝卜中,PBDEs同系物的平均生物有效性分别为48.8%±3.8%、45.2%±5.0%、38.6%±9.3%和37.3%±3.7%。测得菠菜和鲈鱼采用4种混合方式BY1、BY2、BY3和BY4中PBDEs同系物的平均生物有效性分别为17.1%±1.3%、48.3%±3.5%、36.4%±4.9%和44.4%±2.0%,比单纯菠菜（2.6%±0.2%）和鲈鱼（36.3%±4.3%）中的生物有效性高。结果表明,PBDEs的生物有效性随着胡萝卜粒径的增大而减小;不同污染方式再混合食品,比单一食品被污染时,PBDEs的生物有效性更高。

Polybrominated diphenyl ethers are a kind of typical persistent organic pollutants（POPs）. Oral ingestion is the main exposure pathway to human. Chemical oral bioaccessibility plays a key role during the human health risk assessment. The bioaccessibility is the fraction that a chemical released into gastrointestinal digestion solution from its matrix during digestion. It is the maximal fraction that the chemical can be absorbed by intestine. In vitro methods simulating human gastrointestinal digestion process were generally used to test oral bioaccessibility of substances,such as nutrition, heavy metals, and organic pollutants. In the present study, an in vitro method was used to investi-gate the effects of food particle sizes and mixed methods on the bioaccessibility of PBDEs. To study the effect of food particle sizes, PBDEs were spiked into carrot powder with four particle sizes of 150, 150-212, 212-250, and 250 μm. The results showed that the average bioaccessibility of all PBDE congeners in carrot with four particle sizes were 48.8% ± 3.8%, 45.2% ± 5.0%, 38.6% ± 9.3%, and 37.3% ± 3.7%, respectively. To investigate the effects of food mixed methods, PBDEs were first spiked in spinach or perch and mixed them then, or mixed them then PBDEs spiked. According to that, four kinds of samples, i.e., BY1, BY2, BY3, and BY4, were obtained. The results showed that the average bioaccessibility of the PBDE congeners in the four kinds of samples were 17.1% ± 1.3%, 48.3% ± 3.5%, 36.4% ± 4.9%, and 44.4% ± 2.0%, respectively, which were higher than the bioaccessibility in spinach（2.6% ± 0.2%） and perch（36.3% ± 4.3%）. The present results indicated that the bioaccessibility of PBDEs in carrot decreased with the particle sizes increasing. In addition, the bioaccessibility of PBDEs in the mixed foods were higher than that of the single food.