MARE - Marine and Environmental Sciences Centre & ARNET - Aquatic Research Network, ESTM, Politécnico de Leiria, Portugal; Faculdade de Ciências & CESAM, Universidade de Lisboa, Lisboa, Portugal.
MARE - Marine and Environmental Sciences Centre & ARNET - Aquatic Research Network, ESTM, Politécnico de Leiria, Portugal.
Sci Total Environ. 2024 Jun 25;931:172710. doi: 10.1016/j.scitotenv.2024.172710. Epub 2024 Apr 24.
Sea turtles, with their global distribution and complex life cycle, often accumulate pollutants such as metals and metalloids due to their extended lifespan and feeding habits. However, there are limited studies exploring the impact of metal pollution on the reproductive health of female sea turtles, specifically focusing on the quality of their eggs, which has significant implications for the future generations of these charismatic animals. São Tomé Island, a crucial nesting and feeding habitat for green sea turtles, underscores the urgent need for comprehensive research in this ecologically significant area. This study aimed to investigate whether metals and metalloids in the blood of nesting female green sea turtles induce genotoxic effects in their erythrocytes and affect their egg morphometric characteristics and the composition of related compartments. Additionally, this study aimed to evaluate whether the quality of energetic reserves for embryo development (fatty acids in yolk's polar and neutral lipids) is influenced by the contamination status of their predecessors. Results revealed correlations between Cu and Hg levels and increased "lobed" erythrocytes, while As and Cu negatively influenced shell thickness. In terms of energy reserves, both polar and neutral lipid fractions contained primarily saturated and monounsaturated fatty acids, with prevalent 18:1n-9, 18:0, 16:0, 14:0, and 12:0 fatty acids in yolk samples. The yolk polar fraction was more susceptible to contaminant levels in female sea turtles, showing consistent negative correlations between pollution load index and essential n3 fatty acids, including linolenic, eicosatrienoic, eicosapentaenoic, and docosapentaenoic acids, crucial for embryonic development. These metals accumulation, coupled with the reduced availability of these key fatty acids, may disrupt the eicosanoid and other important pathways, affecting reproductive development. This study reveals a negative correlation between metal contamination in female sea turtles' blood and egg lipid reserves, raising concerns about embryonic development and the species' future generations.
海龟分布广泛，生命周期复杂，由于寿命长且摄食习性特殊，常积累金属和类金属等污染物。然而，目前关于金属污染对雌性海龟生殖健康的影响，特别是对其卵质量的影响，研究还很有限，而这对这些魅力四射的动物的后代意义重大。圣多美岛是绿海龟的重要筑巢和觅食栖息地，突显了在这个生态重要区域进行全面研究的紧迫性。本研究旨在探讨血液中金属和类金属是否会在筑巢雌性绿海龟的红细胞中引起遗传毒性作用，并影响其卵形态特征和相关隔室的组成。此外，本研究还旨在评估其前体的污染状况是否会影响胚胎发育的能量储备质量（蛋黄极性和中性脂质中的脂肪酸）。结果表明，Cu 和 Hg 水平与“裂片”红细胞的增加呈正相关，而 As 和 Cu 则负相关影响壳厚度。在能量储备方面，极性和中性脂质均主要含有饱和和单不饱和脂肪酸，蛋黄样品中主要的脂肪酸为 18:1n-9、18:0、16:0、14:0 和 12:0。蛋黄极性部分对雌海龟的污染物水平更为敏感，污染负荷指数与必需 n3 脂肪酸之间存在一致的负相关关系，这些脂肪酸包括亚麻酸、二十碳三烯酸、二十碳五烯酸和二十二碳五烯酸，它们对胚胎发育至关重要。这些金属的积累，加上这些关键脂肪酸的可用性降低，可能会破坏类二十烷酸和其他重要途径，影响生殖发育。本研究揭示了雌性海龟血液中金属污染与卵脂储备之间的负相关关系，这引发了对胚胎发育和该物种后代的担忧。
