Laboratory for Sensory Ecology, Department of Biological Sciences, Bowling Green State University, Bowling Green, OH, 43403, USA.
University of Michigan Biological Station, Pellston, MI, 49769, USA.
Arch Environ Contam Toxicol. 2018 Oct;75(3):436-448. doi: 10.1007/s00244-018-0542-x. Epub 2018 Jun 19.
Chemical pollutants enter aquatic systems through numerous pathways (e.g., surface runoff and ground water contamination), thus associating these contaminant sources with varying hydrodynamic environments. The hydrodynamic environment shapes the temporal and spatial distribution of chemical contaminants through turbulent mixing. The differential dispersal of contaminants is not commonly addressed in ecotoxicological studies and may have varying implications for organism health. The purpose of this study is to understand how differing routes of exposure to atrazine alter social behaviors and physiological responses of aquatic organisms. This study used agonistic encounters in crayfish Orconectes virilis as a behavioral assay to investigate impact of sublethal concentrations of atrazine (0, 40, 80, and 160 µg/L) delivered by methods mimicking ground water and surface runoff influx into flow-through exposure arenas for a total of 23 h. Each experimental animal participated in a dyadic fight trial with an unexposed opponent. Fight duration and intensity were analyzed. Experimental crayfish hepatopancreas and abdominal muscle tissue samples were analyzed for cytochrome P450 and acetylcholinesterase levels to discern mechanism of detoxification and mode of action of atrazine. Atrazine delivered via runoff decreased crayfish overall fight intensity and contrastingly ground water delivery increased overall fight intensity. The behavioral differences were mirrored by increases in cytochrome P450 activity, whereas no differences were found in acetylcholinesterase activity. This study demonstrates that method of delivery into fluvial systems has differential effects on both behavior and physiology of organisms and emphasizes the need for the consideration of delivery pathway in ecotoxicological studies and water-impairment standards.
化学污染物通过多种途径进入水生系统（例如，地表径流和地下水污染），因此将这些污染物来源与不同的水动力环境联系起来。水动力环境通过紊动混合来塑造化学污染物的时空间分布。在生态毒理学研究中，污染物的差异扩散通常未得到解决，并且可能对生物体健康产生不同的影响。本研究的目的是了解接触莠去津的不同途径如何改变水生生物的社会行为和生理反应。本研究使用淡水小龙虾 Orconectes virilis 的争斗行为作为行为测定方法，以研究亚致死浓度莠去津（0、40、80 和 160 µg/L）通过模拟地下水和地表径流进入流动暴露场的不同途径对水生生物的影响，暴露时间总共为 23 小时。每个实验动物都与未暴露的对手进行了二元战斗试验。分析战斗持续时间和强度。对实验小龙虾的肝胰腺和腹部肌肉组织样本进行细胞色素 P450 和乙酰胆碱酯酶水平分析，以辨别莠去津的解毒机制和作用模式。通过径流输送的莠去津降低了小龙虾的整体战斗强度，而相反地，地下水输送则增加了整体战斗强度。行为差异与细胞色素 P450 活性的增加相吻合，而乙酰胆碱酯酶活性没有差异。本研究表明，进入河流系统的输送方式对生物体的行为和生理都有不同的影响，并强调在生态毒理学研究和水损伤标准中需要考虑输送途径。
