The Key Laboratory of Mariculture, Ministry of Education, Ocean University of China, Qingdao, 266003, PR China.
The Key Laboratory of Mariculture, Ministry of Education, Ocean University of China, Qingdao, 266003, PR China.
Ecotoxicol Environ Saf. 2020 Jul 1;197:110558. doi: 10.1016/j.ecoenv.2020.110558. Epub 2020 Apr 15.
The aim of this study was to investigate the bioaccumulation and oxidative damage of Manila clam, Ruditapes philippinarum, exposed to four selected mixtures of polycyclic aromatic hydrocarbons (PAHs; benzo (a) pyrene (BaP), benzo (a) anthracene (BaA), benzo (b) fluoranthene (BbF), and chrysene (Chr) in equal proportion. For this purpose, clams were exposed to PAHs (BaP:BbF:BaA:Chr = 1:1:1:1) at different concentrations (0.05, 0.5, and 5 μg/L) for 21 days, followed by a 15-day depuration period. All four PAHs accumulated in the gill, digestive gland, adductor muscle, and soft tissue of Manila clams, and all PAH treatment groups showed clear time and dose dependence. The decreasing order of bioaccumulation for the four PAHs in the exposure experiment was Chr > BaA > BaP > BbF. Moreover, the order of PAH bioaccumulation for the four tissues during the whole experiment was digestive gland > gill > soft tissues > adductor muscles. Although the initial concentrations of the four PAHs were the same, the final accumulated contents were different. Therefore, we also determined the detoxification processes of the four PAH mixtures in gills and digestive glands. The bioaccumulation of Chr was higher than the other three PAHs, probably because clams have a lower metabolic capacity for Chr than for BaP, BbF, and BaA. Exposure to PAH mixtures can result in oxidative damage, as indicated by the fact that DNA strand breaks, lipid peroxidation (LPO), and protein carbonyl (PC) were induced significantly (P < 0.05), except in the low-dose groups of PAHs, and different trends were detected with time of exposure. According to the correlation analysis, aryl hydrocarbon hydroxylase, glutathione s-transferase, superoxide dismutase, DNA strand break, PC, and LPO in both the gill and digestive gland are potential early indicators of PAH mixtures. We investigated the accumulation rules of R. philippinarum exposed to the selected PAHs and screened the potential biomarkers. The results of our study provide important scientific information for the purpose of monitoring marine pollution.
本研究旨在探究菲律宾蛤仔（Ruditapes philippinarum）在暴露于四种选定多环芳烃（PAHs；苯并[a]芘（BaP）、苯并[a]蒽（BaA）、苯并[b]荧蒽（BbF）和䓛（Chr）以等比例混合的混合物中时的生物累积和氧化损伤情况。为此，将蛤仔暴露于不同浓度（0.05、0.5 和 5μg/L）的 PAHs（BaP:BbF:BaA:Chr=1:1:1:1）中 21 天，随后进行 15 天的净化期。所有四种 PAHs 均在菲律宾蛤仔的鳃、消化腺、闭壳肌和软组织中累积，且所有 PAH 处理组均表现出明显的时间和剂量依赖性。在暴露实验中，四种 PAHs 的生物累积量递减顺序为 Chr>BaA>BaP>BbF。此外，在整个实验过程中，四种组织中 PAH 的生物累积顺序为消化腺>鳃>软组织>闭壳肌。尽管四种 PAH 的初始浓度相同，但最终的累积含量不同。因此，我们还确定了四种 PAH 混合物在鳃和消化腺中的解毒过程。Chr 的生物累积量高于其他三种 PAH，这可能是因为蛤仔对 Chr 的代谢能力低于对 BaP、BbF 和 BaA 的代谢能力。多环芳烃混合物的暴露会导致氧化损伤，这表现在 DNA 链断裂、脂质过氧化（LPO）和蛋白质羰基（PC）显著增加（P<0.05），除了在低剂量的 PAH 组中，且随着暴露时间的不同，呈现出不同的趋势。根据相关性分析，在鳃和消化腺中，芳烃羟化酶、谷胱甘肽 S-转移酶、超氧化物歧化酶、DNA 链断裂、PC 和 LPO 是多环芳烃混合物的潜在早期标志物。我们研究了菲律宾蛤仔暴露于选定的 PAHs 后的累积规律，并筛选了潜在的生物标志物。我们的研究结果为监测海洋污染提供了重要的科学信息。
