He Mei, Ke Cai-Huan, Tian Lei, Li Hai-Bei
Hubei Cooperative Innovation Center of Unconventional Oil and Gas, Yangtze University, Wuhan, 430100, China.
School of Earth Environment and Water Resource, Yangtze University, Wuhan, 430100, China.
Arch Environ Contam Toxicol. 2016 Apr;70(3):595-606. doi: 10.1007/s00244-015-0194-z. Epub 2015 Jul 28.
Bioaccessibility describes the fraction of contaminants released from the food matrix into the digestive tracts of humans, which is beneficial for improving the health risk assessment of contaminants. In this study, the bioaccessibilities of cadmium (Cd), copper (Cu), and zinc (Zn) in two severely contaminated green oyster (Crassostrea angulate) and blue oyster (Crassostrea hongkongensis) populations were investigated. A human health risk assessment of these metals was then performed based on bioaccessibility measurements. Among the three metals, the bioaccessibility was the highest for Cu (42-95%), and Cd and Zn had comparable bioaccessibility (13-58%). There was no major difference in the bioaccessibility between green and blue oysters. A significant correlation between the tissue Cu and Zn concentrations was found in these highly contaminated oysters. A health risk assessment showed that all three metals in both oyster species seriously exceeded the levels recommended by the United States Environmental Protection Agency. Thus, oysters from these locations, and the metals contained therein, presented quite high risks for human consumption, which should be a great cause of concern. A significant relationship was only found between metal bioaccessibility and its tissue concentration instead of between metal bioaccessibility and subcellular distribution. In addition, a significant relationship was only observed between metal health risks and its tissue concentration. The influence of metal bioaccessibilities on the health risks was limited. This may suggest that in the case of the colored oysters examined in this study, metal concentration instead of metal subcellular distribution could be the driving factor of the metal bioaccessibility, and metal concentration, instead of metal bioaccessibility, could be the driving factor of the metal health risks.
生物可及性描述了污染物从食物基质释放到人体消化道中的比例，这有助于改进对污染物的健康风险评估。在本研究中，调查了两个受严重污染的绿牡蛎（近江牡蛎）种群和蓝牡蛎（香港牡蛎）种群中镉（Cd）、铜（Cu）和锌（Zn）的生物可及性。然后基于生物可及性测量结果对这些金属进行了人体健康风险评估。在这三种金属中，铜的生物可及性最高（42%-95%），镉和锌的生物可及性相当（13%-58%）。绿牡蛎和蓝牡蛎的生物可及性没有显著差异。在这些高度污染的牡蛎中，发现组织中铜和锌的浓度之间存在显著相关性。健康风险评估表明，两种牡蛎中的所有三种金属均严重超过了美国环境保护局推荐的水平。因此，来自这些地点的牡蛎及其所含金属对人类消费具有相当高的风险，这应引起高度关注。仅在金属生物可及性与其组织浓度之间发现了显著关系，而不是在金属生物可及性与亚细胞分布之间。此外，仅在金属健康风险与其组织浓度之间观察到显著关系。金属生物可及性对健康风险的影响有限。这可能表明，在本研究中检测的有色牡蛎的情况下，金属浓度而非金属亚细胞分布可能是金属生物可及性的驱动因素，而金属浓度而非金属生物可及性可能是金属健康风险的驱动因素。
