Dehnert Gavin K, White Amber M, Karasov William H
Wisconsin Sea Grant, University of Wisconsin - Madison, Madison, WI, USA.
Department of Civil and Environmental Engineering, University of Wisconsin - Madison, Madison, WI, 53706, USA.
Chemosphere. 2024 Aug;361:142412. doi: 10.1016/j.chemosphere.2024.142412. Epub 2024 May 25.
Aquatic herbicides with active ingredient 2,4-dichlorophenoxyacteic acid (2,4-D) are commonly used to control and combat aquatic non-native species that cause detrimental impacts including habitat destruction, strained resources among biota, and biodiversity loss. While many (eco)toxicology studies are performed in the laboratory under highly controlled circumstances, these studies may disregard the nuances and disorder that come with the complexity of natural aquatic ecosystems. Therefore, we conducted a series of laboratory experiments using laboratory system water, different lake waters, and different water parameters to determine the effects of ecologically relevant concentrations of 2,4-D (0.00-4.00 ppm a.e.) on the development and survival of two freshwater game species (Sander vitreus and Esox lucius). For 2,4-D exposures using different water sources, there were significant main effects of 2,4-D concentration and water source on walleye embryo and larval survival, however, there was no significant interaction between 2,4-D exposure and water source. For 2,4-D exposures and pH (5-9 pH), there were significant main effects of 2,4-D concentration and pH on walleye and northern pike embryo survival and a significant interaction between 2,4-D exposure and pH. Our results indicate that 2,4-D exposures in controlled laboratory system water can predict similar outcomes as 2,4-D exposures in natural lake water. Moreover, individual water parameters, such as pH, play a significant role in the toxicity of 2,4-D. Taken together, these results suggest that highly controlled laboratory studies are a useful tool for predicting impacts on survival of non-target fish in natural waters, but it is crucial for management agencies to consider individual water sources and specific lake water parameters in herbicide risk assessments to minimize the impacts to non-target organism.
含有活性成分2,4-二氯苯氧乙酸（2,4-D）的水生除草剂通常用于控制和对抗造成有害影响的水生非本地物种，这些影响包括栖息地破坏、生物群落间资源紧张以及生物多样性丧失。虽然许多（生态）毒理学研究是在实验室高度受控的条件下进行的，但这些研究可能会忽略自然水生生态系统复杂性所带来的细微差别和无序性。因此，我们进行了一系列实验室实验，使用实验室系统用水、不同的湖水以及不同的水质参数，以确定具有生态相关性的2,4-D浓度（0.00 - 4.00 ppm有效成分）对两种淡水游钓鱼类（大眼狮鲈和白斑狗鱼）发育和存活的影响。对于使用不同水源进行的2,4-D暴露实验，2,4-D浓度和水源对大眼狮鲈胚胎和幼体的存活有显著的主效应，然而，2,4-D暴露与水源之间没有显著的交互作用。对于2,4-D暴露和pH值（5 - 9）的实验，2,4-D浓度和pH值对大眼狮鲈和白斑狗鱼胚胎的存活有显著的主效应，并且2,4-D暴露与pH值之间存在显著的交互作用。我们的结果表明，在受控的实验室系统用水中进行的2,4-D暴露实验能够预测与在天然湖水中进行的2,4-D暴露实验相似的结果。此外，诸如pH值等单个水质参数在2,4-D的毒性方面起着重要作用。综上所述，这些结果表明，高度受控的实验室研究是预测对天然水域中非目标鱼类存活影响的有用工具，但对于管理机构而言，在除草剂风险评估中考虑单个水源和特定的湖水参数以尽量减少对非目标生物的影响至关重要。
