Biology Department & CESAM, University of Aveiro, 3810-193, Aveiro, Portugal.
Chemistry Department & CESAM, University of Aveiro, 3810-193, Aveiro, Portugal.
Environ Pollut. 2022 Jun 15;303:119166. doi: 10.1016/j.envpol.2022.119166. Epub 2022 Mar 16.
Once in the aquatic ecosystems, nanoplastics (NPls) can interact with other contaminants acting as vectors of transport and altering their toxicological effects towards organisms. Thus, the present study aims to investigate how polystyrene NPls (44 nm) interact with the herbicide phenmedipham (PHE) and affect its toxicity to zebrafish embryos. Single exposures to 0, 0.015, 0.15, 1.5, 15 and 150 mg/L NPls and 0.02, 0.2, 2 and 20 mg/L PHE were performed. Embryos were also exposed to the binominal combinations: 0.015 mg/L NPls + 2 mg/L PHE, 0.015 mg/L NPls + 20 mg/L PHE, 1.5 mg/L NPls + 2 mg/L PHE and 1.5 mg/L NPls + 20 mg/L PHE. Due to the low solubility of PHE in water, a solvent control was performed (0.01% acetone). PHE was quantified. Mortality, heartbeat and hatching rate, malformations appearance, locomotor behavior and biomarkers related to oxidative stress, neurotransmission and energy budgets were analyzed. During 96 h, NPls and PHE single and combined exposures did not affect embryos development. After 120 h, NPls induced hyperactivity and PHE induced hypoactivity. After 96 h, NPls increased catalase activity and PHE increased glutathione S-transferases activity. On the combination 0.015 mg/L NPls + 20 mg/L PHE, hyperactivity behavior was found, similar to 0.015 mg/L NPls, and cholinesterase activity was inhibited. Additionally, the combination 1.5 mg/L NPls + 20 mg/L PHE increased both catalase and glutathione S-transferases activities. The combination NPls with PHE affected more biochemical endpoints than the single exposures, showing the higher effect of the binominal combinations. Dissimilar interactions effects - no interaction, synergism and antagonism - between NPls and PHE were found. The current study shows that the effects of NPls on bioavailability and toxicity of other contaminants (e.g. PHE) cannot be ignored during the assessment of NPls environmental behavior and risks.
一旦进入水生生态系统，纳米塑料（NPls）可以与其他污染物相互作用，充当运输载体，并改变它们对生物体的毒理学效应。因此，本研究旨在探讨聚苯乙烯纳米塑料（44nm）如何与除草剂苯草醚（PHE）相互作用，并影响其对斑马鱼胚胎的毒性。分别对 0、0.015、0.15、1.5、15 和 150mg/L NPls 和 0.02、0.2、2 和 20mg/L PHE 进行了单一暴露。胚胎还暴露于二项组合：0.015mg/L NPls+2mg/L PHE、0.015mg/L NPls+20mg/L PHE、1.5mg/L NPls+2mg/L PHE 和 1.5mg/L NPls+20mg/L PHE。由于 PHE 在水中的溶解度较低，因此进行了溶剂对照（0.01%丙酮）。对 PHE 进行了定量分析。死亡率、心跳和孵化率、畸形出现、运动行为以及与氧化应激、神经传递和能量预算相关的生物标志物进行了分析。在 96 小时内，NPls 和 PHE 的单一和联合暴露均未影响胚胎发育。在 120 小时后，NPls 诱导过度活跃，而 PHE 诱导活动减少。在 96 小时后，NPls 增加了过氧化氢酶的活性，而 PHE 增加了谷胱甘肽 S-转移酶的活性。在 0.015mg/L NPls+20mg/L PHE 的组合中，发现了类似于 0.015mg/L NPls 的过度活跃行为，并且胆碱酯酶活性受到抑制。此外，组合 1.5mg/L NPls+20mg/L PHE 增加了过氧化氢酶和谷胱甘肽 S-转移酶的活性。NPls 与 PHE 的组合影响了比单一暴露更多的生化终点，表明二项组合的效果更高。在评估 NPls 的环境行为和风险时，NPls 和 PHE 之间存在不同的相互作用效应-无相互作用、协同作用和拮抗作用。本研究表明，在评估 NPls 的环境行为和风险时，不能忽视 NPls 对其他污染物（如 PHE）的生物利用度和毒性的影响。
