多环芳烃(PAHs)产生于石油的不完全燃烧,煤炭,汽油,具有亲脂性,有利于它们的广泛分布和持久性。由于它们的生化属性,多环芳烃可以在动物组织中积累,可能引起诱变和致癌作用。自工业革命以来,环境中的PAH浓度上升,湖泊的沉积物含量为0.159至33,090μg/kg。尽管急性毒性研究表明对淡水生物有不利影响,与其他污染物的长期影响和协同相互作用在很大程度上仍未被探索。这项研究调查了菲(PHE)的影响,在水生环境中发现的一种突出的PAH,关于大型水蚤,在全球淡水生态系统中具有重要生态意义的物种,既是化学污染的前哨物种,又是淡水水生生态系统中的基石生物。利用D.magna的休眠,跨越几十年甚至几个世纪,我们将具有不同化学污染物暴露史的菌株暴露于环境相关浓度的PHE。最初,急性暴露实验是根据OECD指南对16株水蚤进行的,揭示了急性毒性反应的实质性变化,菌株对化学污染物的毒性最低。利用来自急性暴露的中值效应浓度EC10,我们评估了慢性PHE暴露对16种菌株的生活史特征和生态终点的影响.为了阐明历史上暴露于其他环境应激源如何调节PHE的毒性,利用了从湖中复活的D.magna的时间种群,该湖具有悠久的世纪环境影响历史。我们的发现表明,PHE暴露会导致发育失败,延迟性成熟,并减少水蚤的成年大小。与幼稚人群相比,历史上暴露于化学应激的水蚤人群表现出明显更大的健身影响。这项研究为PAHs与其他环境压力源相互作用的增强效应提供了重要见解。
Polycyclic aromatic hydrocarbons (PAHs) arise from incomplete combustion of oil, coal, and gasoline, with lipophilic properties facilitating their widespread distribution and persistence. Due to their biochemical attributes, PAHs can accumulate in animal tissues, potentially causing mutagenic and carcinogenic effects. Since the industrial revolution, PAH concentrations in the environment have risen, with lakes showing levels from 0.159 to 33,090 μg/kg sediment. Despite acute toxicity studies showing adverse effects on freshwater organisms, the long-term impacts and synergistic interactions with other pollutants remain largely unexplored. This study investigates the impact of phenanthrene (PHE), a prominent PAH found in aquatic environments, on Daphnia magna, a species of significant ecological importance in freshwater ecosystems globally, being both a sentinel species for chemical pollution and a keystone organism in freshwater aquatic ecosystems. Leveraging the dormancy of D. magna, which spans decades or even centuries, we exposed strains with diverse histories of chemical contaminant exposure to environmentally relevant concentrations of PHE. Initially, acute exposure experiments were conducted in accordance with OECD guidelines across 16 Daphnia strains, revealing substantial variation in acute toxic responses, with strains naïve to chemical pollutants showing the lowest toxicity. Utilizing the median effect concentration EC10 derived from acute exposures, we assessed the impacts of chronic PHE exposure on life history traits and ecological endpoints of the 16 strains. To elucidate how historical exposure to other environmental stressors may modulate the toxicity of PHE, temporal populations of D. magna resurrected from a lake with a well-documented century-spanning history of environmental impact were utilized. Our findings demonstrate that PHE exposure induces developmental failure, delays sexual maturation, and reduces adult size in Daphnia. Populations of Daphnia historically exposed to chemical stress exhibited significantly greater fitness impacts compared to naïve populations. This study provides crucial insights into the augmented effects of PAHs interacting with other environmental stressors.