Department of Ecology and Coastal Management, Institute of Marine Sciences of Andalusia (CSIC), 11510, Puerto Real, Cádiz, Spain.
Department of Ecology and Coastal Management, Institute of Marine Sciences of Andalusia (CSIC), 11510, Puerto Real, Cádiz, Spain; Department of Physical Chemistry, Faculty of Marine and Environmental Sciences, CEI-MAR, University of Cadiz, 11510, Puerto Real, Spain.
Chemosphere. 2019 Nov;235:126-135. doi: 10.1016/j.chemosphere.2019.06.139. Epub 2019 Jun 21.
As the exposure of organisms to contaminants can provoke harmful effects, some organisms try to avoid a continuous exposure by using different strategies. The aim of the current study was to assess the ability of the shrimp Palaemon varians to detect a triclosan gradient and escape to less contaminated areas. Two multi-compartmented exposure systems (the linear system and the HeMHAS-Heterogeneous Multi-Habitat Assay System) were used and then results were compared. Finally, it was aimed how sensitive the avoidance response is by comparing it with other endpoints through a sensitivity profile by biological groups and the species sensitive distribution. The distribution of the shrimps along the triclosan gradient was dependent on the concentrations, not exceeding 3% for 54 μg/L in the linear system and 7% for 81 μg/L in the HeMHAS; 25% of organisms preferred the compartment with the lowest concentrations in both systems. Half of the population seems to avoid concentrations around 40-50 μg/L. The triclosan concentration that might start (threshold) to trigger an important avoidance (around 20%) was estimated to be of 18 μg/L. The profile of sensitivity to triclosan showed that avoidance by shrimps was less sensitive than microalgae growth and avoidance by guppy; however, it might occur even at concentrations considered safe for more than 95% of the species. In summary, (i) the HeMHAS proved to be a suitable system to simulate heterogeneous contamination scenarios, (ii) triclosan triggered the avoidance response in P. varians, and (iii) the avoidance was very sensitive compared to other ecotoxicological responses.
由于生物体暴露于污染物会引发有害影响，因此一些生物体试图通过使用不同的策略来避免持续暴露。本研究旨在评估虾 Palaemon varians 检测三氯生梯度并逃避到污染较少区域的能力。使用了两种多隔室暴露系统（线性系统和 HeMHAS-多栖息地异质分析系统），然后比较了结果。最后，通过生物群和物种敏感分布的敏感性分布，比较了与其他终点的逃避反应的敏感性，以确定逃避反应的敏感性如何。虾在三氯生梯度中的分布取决于浓度，在线性系统中，浓度不超过 54μg/L 时为 3%，在 HeMHAS 中，浓度不超过 81μg/L 时为 7%；在这两个系统中，有 25%的生物体更喜欢浓度最低的隔室。一半的种群似乎避免了 40-50μg/L 左右的浓度。估计可能开始（阈值）触发重要逃避（约 20%）的三氯生浓度为 18μg/L。对三氯生的敏感性分布表明，虾的逃避敏感性低于微藻生长和孔雀鱼的逃避敏感性；然而，即使在超过 95%的物种认为安全的浓度下，也可能发生逃避。总之，(i)HeMHAS 被证明是模拟异质污染情景的合适系统，(ii)三氯生引发了 P. varians 的逃避反应，(iii)与其他生态毒理学反应相比，逃避反应非常敏感。
