Zaluski Amanda B, Wiprich Melissa T, de Almeida Luiza F, de Azevedo Andressa P, Bonan Carla D, Vianna Monica R M
Laboratório de Biologia e Desenvolvimento do Sistema Nervoso, Escola de Ciências da Saúde e da Vida, Pontifícia Universidade Católica do Rio Grande do Sul, Porto Alegre, Brazil.
Laboratório de Neuroquímica e Psicofarmacologia, Escola de Ciências da Saúde e da Vida, Pontifícia Universidade Católica do Rio Grande do Sul, Porto Alegre, Brazil.
Front Pharmacol. 2022 Apr 4;13:841826. doi: 10.3389/fphar.2022.841826. eCollection 2022.
Atrazine and Diuron are widely used herbicides. The use of pesticides contaminates the aquatic environment, threatening biodiversity and non-target organisms such as fish. In this study, we investigated the effects of acute exposure for 96 h hours to atrazine and diuron commercial formulations in zebrafish (, wild-type AB) embryos and larvae and adult stages. We observed a significant concentration-dependent survival decrease and hatching delays in animals exposed to both herbicides and in the frequency of malformations compared to the control groups. Morphological defects included cardiac edema, tail reduction, and head malformation. At 7 days post-fertilization (dpf), atrazine exposure resulted in a reduction in the head length at 2, 2.5, and 5 mg/L and increased the ocular distance at 1, 2, 2.5, and 5 mg/L atrazine when compared to controls. At the same age, diuron increased the ocular distance in animals exposed to diuron (1.0 and 1.5 mg/L) and no effects were observed on the head length. We also evaluated a behavioral repertoire in larvae at 7 dpf, and there were no significant differences in distance traveled, mean speed, time in movement, and thigmotaxis for atrazine and diuron when animals were individually placed in a new environment. The cognitive ability of the larvae was tested at 7 dpf for avoidance and optomotor responses, and neither atrazine nor diuron had significant impacts when treated groups were compared to their corresponding controls. Adults' behavior was evaluated 7 and 8 days after the end of the acute herbicide exposure. Exploration of a new environment and associated anxiety-like parameters, social interaction, and aggressiveness were not altered. Our results highlight the need for further studies on the sublethal effects of both herbicides and the consideration of the effects of commercial formulas vs. isolated active ingredients. It also emphasizes the need to take sublethal effects into consideration when establishing the environmental limits of residues.
莠去津和敌草隆是广泛使用的除草剂。农药的使用会污染水环境，威胁生物多样性以及鱼类等非目标生物。在本研究中，我们调查了斑马鱼（野生型AB）胚胎、幼虫和成鱼阶段急性暴露于莠去津和敌草隆商业制剂96小时的影响。与对照组相比，我们观察到暴露于这两种除草剂的动物出现了显著的浓度依赖性存活率下降、孵化延迟以及畸形频率增加的情况。形态学缺陷包括心脏水肿、尾部缩短和头部畸形。受精后7天（dpf），与对照组相比，暴露于2、2.5和5mg/L莠去津会导致头部长度缩短，而暴露于1、2、2.5和5mg/L莠去津会使眼间距增加。在相同年龄时，敌草隆会使暴露于敌草隆（1.0和1.5mg/L）的动物眼间距增加，且未观察到对头部长度有影响。我们还评估了7dpf幼虫的行为表现，当将动物单独置于新环境中时，莠去津和敌草隆在游动距离、平均速度、活动时间和趋触性方面没有显著差异。在7dpf时测试了幼虫的认知能力以评估回避和视动反应，与相应对照组相比，莠去津和敌草隆均未产生显著影响。在急性除草剂暴露结束后7天和8天评估了成鱼的行为。对新环境的探索以及相关的焦虑样参数、社交互动和攻击性均未改变。我们的结果凸显了有必要进一步研究这两种除草剂的亚致死效应，以及考虑商业配方与分离活性成分的影响。这也强调了在确定残留的环境限值时需要考虑亚致死效应。
