Zhang Jichao, Tan Qiao-Guo, Huang Liping, Ye Zijun, Wang Xiaohong, Xiao Tangfu, Wu Yun, Zhang Wei, Yan Bing
Institute of Environmental Research at Greater Bay Area, Key Laboratory for Water Quality and Conservation of the Pearl River Delta, Ministry of Education, Guangzhou University, Guangzhou 510006, China.
Key Laboratory of the Coastal and Wetland Ecosystems, Ministry of Education, College of Environment and Ecology, Xiamen University, Xiamen 361102, China.
J Hazard Mater. 2022 Jul 15;434:128904. doi: 10.1016/j.jhazmat.2022.128904. Epub 2022 Apr 13.
Arsenate [As(V)] is the main form of arsenic (As) present in freshwater taken up by freshwater fish. Data on the main uptake tissue, biotransformation, and bioaccumulation in freshwater fish exposed to As(V) were limited, and the reasons for its bioaccumulation in the muscle tissue of freshwater fish remain undetermined. Accordingly, we simulated bioaccumulation and depuration in zebrafish (Danio rerio) exposed to waterborne As(V) by employing a six-compartment physiologically based pharmacokinetic model and As speciation analysis. Modeling and biotransformation suggested that intestines were the main uptake site for waterborne As(V), instead of the gills. This novel finding was evidenced by the higher As transfer constant from water to intestines (k = 1.52 × 10 L d) compared to gills (k = 5.28 × 10 L d). The low concentration and percentage of arsenobetaine (AsB) in the intestines suggested a weak ability to synthesize AsB. Our results showed a substantial proportion of inorganic As in intestines and a relatively substantial percentage in muscle tissue. Therefore, high As(V) uptake in the intestines and lack of biotransformation contributed to high bioaccumulation of inorganic As in freshwater fish. Inorganic As posed concerns due to the human health risks associated with consuming As(V)-contaminated fish and should be addressed.
砷酸盐[As(V)]是淡水鱼所摄取的淡水中砷（As）的主要存在形式。关于暴露于As(V)的淡水鱼的主要摄取组织、生物转化和生物累积的数据有限，其在淡水鱼肌肉组织中生物累积的原因仍未确定。因此，我们通过采用六室生理药代动力学模型和砷形态分析，模拟了暴露于水体As(V)的斑马鱼（Danio rerio）中的生物累积和净化过程。建模和生物转化表明，肠道是水体As(V)的主要摄取部位，而非鳃。与鳃（k = 5.28×10 L d）相比，从水到肠道的砷转移常数更高（k = 1.52×10 L d），这一新颖发现得到了证实。肠道中砷甜菜碱（AsB）的低浓度和低比例表明其合成AsB的能力较弱。我们的结果显示，肠道中无机砷的比例相当大，肌肉组织中的比例也相对较高。因此，肠道对As(V)的高摄取和缺乏生物转化导致了淡水鱼体内无机砷的高生物累积。由于食用受As(V)污染的鱼类会带来人类健康风险，无机砷令人担忧，应予以关注。
