Department of Environmental Science, Center for Reservoir and Aquatic Systems Research, Baylor University, Waco, TX, USA; Department of Chemistry and Biochemistry, Center for Reservoir and Aquatic Systems Research, Baylor University, Waco, TX, USA.
Department of Environmental Science, Center for Reservoir and Aquatic Systems Research, Baylor University, Waco, TX, USA.
Sci Total Environ. 2020 Sep 20;736:139603. doi: 10.1016/j.scitotenv.2020.139603. Epub 2020 May 22.
Whether seasonal instream flow dynamics influence bioaccumulation of pharmaceuticals by fish is not well understood, specifically for urban lotic systems in semi-arid regions when flows are influenced by snowmelt. We examined uptake of select pharmaceuticals in rainbow trout (Oncorhynchus mykiss) caged in situ upstream and at incremental distances downstream (0.1, 1.4, 13 miles) from a municipal effluent discharge to East Canyon Creek in Park City, Utah, USA during summer and fall of 2018. Fish were sampled over 7-d to examine if uptake occurred, and to define uptake kinetics. Water and fish tissues were analyzed via isotope dilution liquid chromatography tandem mass spectrometry. Several pharmaceuticals were consistently detected in water, fish tissue and plasma, including carbamazepine, diphenhydramine, diltiazem, and fluoxetine. Pharmaceutical levels in water ranged up to 151 ng/L for carbamazepine, whereas the effluent tracer sucralose was consistently observed at low μg/L levels. During both summer and fall experiments at each of three downstream locations from effluent discharge, rainbow trout rapidly accumulated these pharmaceuticals; tissue levels reached steady state conditions within 24-96 h. Spatial and temporal differences for pharmaceutical levels in rainbow trout directly corresponded with surface water exposure concentrations, and uptake kinetics for individual pharmaceuticals did not vary among sites or seasons. Such observations are consistent with recent laboratory bioconcentration studies, which collectively indicate inhalational exposure from water governs rapid accumulation of ionizable base pharmaceuticals by fish in inland surface waters.
季节性河道内水流动态是否会影响鱼类对药物的生物积累尚不清楚，特别是在半干旱地区的城市流水系统中，当水流受到融雪影响时更是如此。我们研究了选择的药物在虹鳟鱼（Oncorhynchus mykiss）中的吸收情况，这些虹鳟鱼被关在笼子里，位于美国犹他州帕克城的东峡谷溪从市政废水排放口上游和下游不同距离处（0.1、1.4 和 13 英里）。在 2018 年夏季和秋季，我们对鱼进行了为期 7 天的采样，以检查是否发生了吸收，并确定吸收动力学。通过同位素稀释液相色谱串联质谱法分析水和鱼组织。在水中、鱼组织和血浆中检测到几种药物，包括卡马西平、苯海拉明、地尔硫卓和氟西汀。水中的药物浓度高达 151ng/L 的卡马西平，而废水示踪剂蔗糖素则一直以低μg/L 的水平存在。在夏季和秋季的实验中，在距离废水排放口三个下游位置的每个位置，虹鳟鱼都迅速积累了这些药物；24-96 小时内，组织水平达到稳定状态。虹鳟鱼体内药物水平的时空差异与地表水中的暴露浓度直接相关，个别药物的吸收动力学在不同地点或季节之间没有差异。这些观察结果与最近的实验室生物浓缩研究一致，这些研究表明，鱼类在内陆地表水中对可电离碱性药物的快速积累是由水中的吸入暴露决定的。
