Polycyclic aromatic hydrocarbons (PAHs) are priority contaminants in coastal and estuarine ecosystems under anthropogenic pressure. Although PAHs tend to accumulate in the sediment, toxicity for benthic flat fish such as soles may be caused by PAHs released from the sediment to the water column. Within this context, the present investigation aims at recognizing toxicopathic effects elicited after waterborne exposure to benzo[a]pyrene B[a]P, a model individual PAH compound, in juvenile Solea senegalensis. Sole juveniles were exposed to various concentrations of waterborne B[a]P for 3 and 7 days. Brain, liver, gills and gonad were the target tissues selected to determine biochemical and lysosomal biomarkers, and histopathology. Biological responses and toxicopathic effects were consistent with B[a]P concentration and exposure time. From day 3, hepatic catalase inhibition indicated potential oxidative effects of B[a]P. At day 7, contaminant exposure produced hepatic glutathione-S-transferase induction at low concentrations and inhibition at higher levels, evidencing a bell-shaped response. A clear gradient in lysosomal membrane destabilisation was observed in relation with B[a]P concentrations. Histopathological lesions were more frequent at day 7 and at higher contaminant levels. It seems that environmentally relevant waterborne concentrations of B[a]P (1000 ng/l) would suffice to cause toxicopathic effects on sole juveniles in relatively short exposure times. In agreement, the Integrative Biological Response index (IBR/n) indicated a dose-dependent decline in health condition upon exposure to B[a]P (IBR/n_HighB[a]P > IBR/n_MidB[a]P > IBR/n_LowB[a]P > IBR/n_DMSO > IBR/n_Control). Overall, changes in antioxidant enzymes activity, lysosomal biomarkers and gill and liver histopathology are responsive early-warning signs of health disturbance in sole juveniles exposed to waterborne PAHs.

多环芳烃 (PAH) 是沿海和河口生态系统在人为压力下的优先污染物。虽然多环芳烃倾向于在沉积物中积累，但对底栖比目鱼（如比目鱼）的毒性可能是由沉积物中释放到水体中的多环芳烃引起的。在此背景下，本研究旨在识别水源性接触苯并 [a] 芘 B[a]P（一种模型个体多环芳烃化合物）后在幼鱼Solea senegalensis 中引起的毒理学效应. 单独的幼鱼暴露于不同浓度的水性 B[a]P 中 3 天和 7 天。大脑、肝脏、鳃和性腺是选定的目标组织，用于确定生化和溶酶体生物标志物以及组织病理学。生物反应和毒理学效应与 B[a]P 浓度和暴露时间一致。从第 3 天起，肝脏过氧化氢酶抑制表明 B[a]P 具有潜在的氧化作用。在第 7 天，污染物暴露产生了肝谷胱甘肽-S- 低浓度下的转移酶诱导和较高水平下的抑制，证明了钟形反应。观察到与 B[a]P 浓度相关的溶酶体膜不稳定的明显梯度。组织病理学病变在第 7 天和更高的污染物水平更频繁。似乎与环境相关的水性 B[a]P 浓度 (1000 ng/l) 足以在相对较短的暴露时间内对单一幼鱼造成毒理学影响。一致认为，综合生物反应指数 (IBR/n) 表明暴露于 B[a]P 后健康状况呈剂量依赖性下降（IBR/n _HighB[a]P  > IBR/n _MidB[a]P  > IBR /n _LowB[a]P  > IBR/n _DMSO  > IBR/n_控制）。总体而言，抗氧化酶活性、溶酶体生物标志物以及鳃和肝脏组织病理学的变化是暴露于水性多环芳烃的单一幼鱼健康紊乱的早期预警信号。