Laboratório de Biogeoquímica Costeira, Instituto de Ciências do Mar, Universidade Federal do Ceará, Av. Abolição, 3207, Fortaleza, Ceará, 60165-081, Brasil.
Bull Environ Contam Toxicol. 2023 May 27;110(6):99. doi: 10.1007/s00128-023-03745-1.
Scutes present very complex morphologies with different growth rates at different areas of the carapace that can change the accumulation process of essential and non-essential metals. To infer the effects of morphology and growth on Hg concentrations in scutes, we mapped them in the carapace of one individual of four species of sea turtles sampled along the Brazilian coast. The results showed that Hg concentrations were higher in the vertebral scutes of Chelonia mydas and Eretmochelys imbricata suggesting variation in growth rates of different carapace areas since the vertebral area is the first to develop prior to costal areas. Caretta caretta and Lepidochelys olivacea did not show differences between carapace areas. The preliminary data from this pilot study indicate that vertebral scutes may be suitable for monitoring Hg in C. mydas and E. imbricata, since they reflect longer exposure period. A species-to-species comparison of Hg concentrations is not possible due to the small number of sampled individuals, nevertheless, E. imbricata showed remarkably lower Hg concentrations compared to the other three species. Further studies are required for all four species, with a larger number of individuals, preferentially of varying life stages, due to the unknown effects of different diets, Hg exposure, and migration histories.
盾片呈现出非常复杂的形态，其不同区域的生长速度也不同，这可能会改变必需和非必需金属的积累过程。为了推断形态和生长对盾片中汞浓度的影响，我们对沿巴西海岸采集的四种海龟个体的甲壳上的盾片进行了定位。结果表明，在玳瑁和绿海龟的脊椎盾片中，汞浓度较高，这表明不同甲壳区域的生长速度存在差异，因为脊椎区域是在肋部区域之前首先发育的。由于样本数量较少，因此，在棱皮龟和丽龟中，甲壳区域之间没有差异。这项初步研究的初步数据表明，脊椎盾片可能适合监测玳瑁和绿海龟中的汞，因为它们反映了更长的暴露期。由于不同饮食、汞暴露和迁移历史的未知影响，无法对四种物种的汞浓度进行物种间比较。由于未知的不同饮食、汞暴露和迁移历史的影响，所有四种物种都需要进行更多的研究，样本数量要更大，最好涵盖不同的生命阶段。
