Department of Environmental Science and Policy, University of Milan, via Celoria 2, I-20133 Milan, Italy.
Department of Environmental Science and Policy, University of Milan, via Celoria 2, I-20133 Milan, Italy.
Environ Pollut. 2018 Jan;232:236-244. doi: 10.1016/j.envpol.2017.09.038. Epub 2017 Sep 18.
Several monitoring studies have shown that benzoylecgonine (BE) is the main illicit drug residue commonly measured in the aquatic system worldwide. Few studies have investigated the potential toxicity of this molecule towards invertebrate and vertebrate aquatic non-target organisms focusing on effects at low levels of the biological organization, but no one has assessed the consequences at higher ones. Thus, the present study was aimed at investigating the toxicity of a 48-h exposure to two concentrations of BE, similar to those found in aquatic ecosystems (0.5 μg/L and 1.0 μg/L), on the cladoceran Daphnia magna at different levels of the ecological hierarchy. We relied on a multi-level approach focusing on the effects at biochemical/biomolecular (biomarkers), individual (swimming activity) and population (reproduction) levels. We measured the amount of reactive oxygen species and of the activity of antioxidant (SOD, CAT, and GPx) and detoxifying (GST) enzymes to assess if BE exposure can alter the oxidative status of D. magna specimens, while the lipid peroxidation (TBARS) was measured as a marker of oxidative damage. Moreover, we also measured the acetylcholinesterase (AChE) activity because it is strictly related to behavioral changes in aquatic organisms. Changes in swimming behavior were investigated by a video tracking analysis, while the consequences on reproduction were assessed by a chronic toxicity test. Our results showed that BE concentrations similar to those found in aquatic ecosystems induced oxidative stress and inhibited AChE activity, affecting swimming behavior and the reproduction of Daphnia magna individuals.
几项监测研究表明，苯甲酰爱康宁（BE）是全球水生系统中普遍检测到的主要非法药物残留。少数研究调查了该分子对无脊椎动物和脊椎动物水生非目标生物的潜在毒性，重点关注低水平的生物组织效应，但没有人评估过高水平的后果。因此，本研究旨在调查在类似于水生生态系统中发现的两种浓度（0.5μg/L 和 1.0μg/L）BE 暴露 48 小时对处于不同生态层次的枝角类动物大型溞（Daphnia magna）的毒性。我们依赖于一种多层次的方法，重点关注生物化学/生物分子水平（生物标志物）、个体（游泳活动）和种群（繁殖）的影响。我们测量了活性氧的数量和抗氧化（SOD、CAT 和 GPx）和解毒（GST）酶的活性，以评估 BE 暴露是否会改变 D. magna 标本的氧化状态，而脂质过氧化（TBARS）被测量为氧化损伤的标志物。此外，我们还测量了乙酰胆碱酯酶（AChE）的活性，因为它与水生生物的行为变化密切相关。游泳行为的变化通过视频跟踪分析进行了研究，而繁殖的后果则通过慢性毒性试验进行了评估。我们的研究结果表明，与水生生态系统中发现的浓度相似的 BE 会引起氧化应激并抑制 AChE 活性，从而影响大型溞个体的游泳行为和繁殖。
