Laboratoire d'Ingénierie de l'Environnement et d'Ecotechnologie, ENIS, Université de Sfax, BP 1173, 3038, Sfax, Tunisia.
Centro Interdisciplinar de Investigação Marinha e Ambiental (CIIMAR/CIMAR), Terminal de Cruzeiros do Porto de Leixões, Av. General Norton de Matos S/N, 4450-208, Porto, Matosinhos, Portugal.
Environ Sci Pollut Res Int. 2019 Oct;26(29):29704-29721. doi: 10.1007/s11356-019-05872-x. Epub 2019 Aug 12.
Coastal marine areas are highly vulnerable to the exposure to various types of stressors and impact of chemical pollution resulting from increasing anthropogenic activities, namely pollution by metals and polycyclic aromatic hydrocarbons (PAHs). To assess ecosystem quality and functions, biomarkers can provide information about the presence and adverse effects of pollutants. Accordingly, the present study was conducted to evaluate the chronic (28 days) biologic effects of putatively contaminated sediments from the Zarzis area, located in the south of the Gulf of Gabes on the Southern Tunisian coast, on the marine flatfish Solea senegalensis. Sediments were collected at three sampling sites, impacted by wastewater discharges, aquaculture activities, and industrial contamination, and then surveyed for metals (Cd, Cu, Cr, Hg, Zn, and Pb) and organic contaminants (polycyclic aromatic hydrocarbons). The quantified biomarkers involved the determination of oxidative stress, phase II metabolism, and the extent of lipid peroxidation (catalase, CAT; glutathione peroxidase activity: total and selenium-dependent, T-GPx and Se-GPx; activities of glutathione-S-transferases, GSTs; levels of lipid peroxidation, by means of the thiobarbituric acid reactive substances assay, TBARS) and neurotoxicity (activity of acetylcholinesterase, AChE). S. senegalensis exposed to potentially contaminated sediments, collected near the aquaculture facility, presented the highest values for the generality of biomarkers tested, and a significant inhibition of AChE activity. A few lesions have been also recorded in the gills and liver tissues of S. senegalensis following chronic exposure. However, the observed lesions in gills (e.g., epithelial lifting, lamellar fusion, gills hyperplasia and hypertrophy, and leukocyte infiltration) and liver (cytoplasmic vacuolation, enlargement of sinusoids, foci of necrosis, and eosinophilic bodies) were of minimal pathological importance and/or low prevalence that did not significantly affect the weighted histopathological indices. Finally, the biological responses evidenced by this flatfish can be potentially caused by metal and PAH pollution occurring in specific areas in the southeast of Tunisia. The type and extent of the observed biochemical alterations strongly suggest that the contaminated sediments from the surveyed areas could cause early adverse biological effects on exposed biota.
滨海海洋区域极易受到各种类型的压力源的影响，也容易受到人为活动造成的化学污染的影响，例如金属和多环芳烃 (PAHs) 的污染。为了评估生态系统的质量和功能，生物标志物可以提供污染物存在和不良影响的信息。因此，本研究旨在评估位于突尼斯南部加贝斯湾南部的扎尔齐斯地区受污染沉积物对海洋比目鱼塞内加尔鳎的慢性（28 天）生物学影响。在受废水排放、水产养殖活动和工业污染影响的三个采样点采集沉积物，并对其进行金属（Cd、Cu、Cr、Hg、Zn 和 Pb）和有机污染物（多环芳烃）的检测。量化的生物标志物涉及氧化应激、二期代谢和脂质过氧化程度（过氧化氢酶，CAT；谷胱甘肽过氧化物酶活性：总和硒依赖，T-GPx 和 Se-GPx；谷胱甘肽-S-转移酶的活性，GSTs；通过硫代巴比妥酸反应物质测定法测定脂质过氧化水平，TBARS）和神经毒性（乙酰胆碱酯酶活性，AChE）的测定。在水产养殖设施附近采集的可能受到污染的沉积物中，塞内加尔鳎暴露于其中，其测试的生物标志物的总体值最高，且 AChE 活性受到显著抑制。在慢性暴露后，塞内加尔鳎的鳃和肝脏组织中也记录到一些病变。然而，在鳃（如上皮细胞提起、瓣融合、鳃增生和肥大以及白细胞浸润）和肝脏（细胞质空泡化、窦扩张、坏死灶和嗜酸性小体）中观察到的病变，其病理学意义不大/低流行率，并未显著影响加权组织病理学指数。最后，这种比目鱼表现出的生物学反应可能是由突尼斯东南部特定地区的金属和 PAH 污染引起的。观察到的生化变化的类型和程度强烈表明，调查区域的受污染沉积物可能会对暴露生物群造成早期的不良生物学影响。
