Abstract:
Anthracene (Anth) and pyrene (Pyr), two of the priority polycyclic aromatic hydrocarbons (PAHs), being lipophilic in nature, not only accumulate in animals, but also settle in the sediment of water bodies leading to continuous exposure for animals. Anth and Pyr when exposed to sunlight can be photoactivated and have harmful effects on aquatic organisms. A comparative analysis was carried out to assess the acute, sub-chronic, genetic and biochemical toxicity of Anth and Pyr in F. limnocharis tadpoles following short exposures to sunlight on a daily basis. In the bioaccumulation studies, it was found that both Anth and Pyr accumulated in the tadpole tissues in a concentration and time dependent manner. The LC50 values for Anth (under 15 min of daily sunlight exposure) were found to be 2.87, 2.59, 2.28, 1.80 mg/L at 24, 48, 72 and 96 h of the exposures. The corresponding LC50 values for Pyr were 1.03, 0.80, 0.62, 0.42 mg/L. Sublethal exposure of Anth and Pyr affected the survivality, time to metamorphosis as well as morphometric parameters under sunlight exposure. In the genotoxicity assessment studies, particularly the micronucleus test and comet assay, it was found that Pyr led to a higher incidence of micronucleus formation and DNA damage in comparison to Anth. The exposure to PAHs resulted in significant changes in the activity of antioxidant-mediated protective response, specifically the SOD activity, which varied between the groups treated with Anth and Pyr. On the other hand, Pyr treated group showed a higher level of GSH as compared to Anth treated groups. Moreover, the elevation in MDA level in the Anth and Pyr treated groups suggests an increase in lipid peroxidation. Future research should focus on understanding the ecotoxicological risk faced by anuran amphibia due to PAHs that frequently occur in aquatic environments and developing strategies to mitigate these risks.
摘要:
蒽(安)和芘(Pyr),两种优先多环芳烃(PAHs),具有亲脂性,不仅在动物体内积累,但也会沉淀在水体的沉积物中,导致动物持续暴露。当暴露在阳光下时,Anth和Pyr可以被光活化并对水生生物产生有害影响。进行了比较分析,以评估急性,亚慢性,每天短暂暴露于阳光下,对F.limnocharist的Anth和Pyr的遗传和生化毒性。在生物蓄积性研究中,发现Anth和Pyr均以浓度和时间依赖性方式在the组织中积累。在暴露的24、48、72和96小时,发现Anth的LC50值(每天暴露15分钟以下)为2.87、2.59、2.28、1.80mg/L。Pyr的相应LC50值为1.03、0.80、0.62、0.42mg/L。Anth和Pyr的亚致死暴露影响了生存率,在阳光照射下的变态时间以及形态参数。在遗传毒性评估研究中,特别是微核试验和彗星试验,发现与Anth相比,Pyr导致更高的微核形成和DNA损伤发生率。暴露于PAHs导致抗氧化剂介导的保护性反应的活性发生显著变化,特别是SOD活性,在用Anth和Pyr治疗的组之间有所不同。另一方面,与Anth治疗组相比,Pyr治疗组显示更高水平的GSH。此外,Anth和Pyr治疗组MDA水平升高表明脂质过氧化增加。未来的研究应集中在了解水生环境中经常发生的PAHs引起的无性系两栖动物面临的生态毒理学风险,并制定减轻这些风险的策略。