Key Laboratory of Marine Hazards Forecasting, Ministry of Natural Resources, Hohai University, Nanjing, Jiangsu 210098, PR China; College of Oceanography, Hohai University, Nanjing, Jiangsu 210098, PR China; Key Laboratory for Earth Surface Processes, College of Urban and Environmental Sciences, Peking University, Beijing 100871, PR China.
State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, PR China.
Water Res. 2020 Oct 1;184:116164. doi: 10.1016/j.watres.2020.116164. Epub 2020 Jul 10.
Methamphetamine (METH) has been recognized as an emerging organic contaminant as it was widely detected in the aquatic environment via wastewater effluent discharge. However, the ecological hazard posed by METH at environmentally relevant concentrations was remained unclear. In this study, adult medaka fish were exposed to METH at environmental levels (0.05, 0.2, 0.5, 5 μg L) and high level (25 and 100 μg L) for 90 days to investigate its effect on ecologically behavioral functions, histopathology, bioconcentration, and transgenerational toxicity. The significant increase of locomotion activity, total distance, and max velocity of adult medaka were observed at low METH levels (0.2-0.5 μg L), while it markedly decreased at high levels (25-100 μg L). This effect may increase the predation risk of the fish. The significant alteration on the relative expressions of the genes (cacna1c, oxtr, erk1, and c-fos), as well as the contents of the proteins (oxytocin (OXT) and protein kinase A (PKA)) involved in Voltage Dependent Calcium Channel (VDCC) and Mitogen-Activated Protein Kinase (MAPK) signaling channel induced by METH could partly elucidate the underlying mechanisms of the changes of the behavioral traits. METH could induce obvious minimal gliosis, neuronal loss, and necrotic in brain tissues. Additionally, the significant increase of hepatic-somatic index (HSI) of male medaka at 0.2-5 μg L groups, and the decrease of female medaka at 100 μg L group indicated male fish was more susceptible to METH. Nephric-somatic index (NSI) of medaka markedly declined induced by METH at 0.05-100 μg L. The bioconcentration factor (BCF) (0.4-5.8) in medaka fish revealed the bioconcentration potential of METH in fish. This study for the first time demonstrated METH could induced the development defects of larvae in F1 generation at environmentally relevant concentrations, thereby resulting in a significant decrease in the capacity of fish to produce offspring. Meanwhile, the RQ values (>1) of METH in river in China, USA, and Australia showed a high teratogenic risk level, suggesting the ecosystem-levels consequence posed by METH should be concerned.
甲基苯丙胺（METH）已被确认为一种新兴的有机污染物，因为它通过废水排放广泛存在于水环境中。然而，METH 在环境相关浓度下造成的生态危害仍不清楚。在这项研究中，成年斑马鱼在环境水平（0.05、0.2、0.5、5μg/L）和高浓度（25 和 100μg/L）下暴露 90 天，以研究其对生态行为功能、组织病理学、生物浓缩和跨代毒性的影响。在低 METH 水平（0.2-0.5μg/L）下，成年斑马鱼的运动活性、总距离和最大速度显著增加，而在高浓度（25-100μg/L）下则显著降低。这种影响可能会增加鱼类的捕食风险。参与电压依赖性钙通道（VDCC）和丝裂原激活蛋白激酶（MAPK）信号通道的基因（cacna1c、oxtr、erk1 和 c-fos）以及蛋白质（催产素（OXT）和蛋白激酶 A（PKA））的相对表达的显著改变，部分阐明了行为特征变化的潜在机制。METH 可引起脑组织中明显的轻微神经胶质增生、神经元缺失和坏死。此外，0.2-5μg/L 组雄性斑马鱼的肝体指数（HSI）显著增加，100μg/L 组雌性斑马鱼的 HSI 减少，表明雄性鱼对 METH 更敏感。METH 可显著降低斑马鱼的肾体指数（NSI），浓度范围为 0.05-100μg/L。斑马鱼的生物浓缩系数（BCF）（0.4-5.8）表明 METH 在鱼类中有生物浓缩的潜力。本研究首次证明 METH 可在环境相关浓度下诱导 F1 代幼虫发育缺陷，从而导致鱼类繁殖能力显著下降。同时，中国、美国和澳大利亚河流中 METH 的 RQ 值（>1）表明其具有高致畸风险水平，这表明应关注 METH 对生态系统水平造成的后果。
