Jian Li, Zhang Ting, Lin Liu, Xiong Jinfang, Shi Haitao, Wang Jichao
Ministry of Education Key Laboratory for Ecology of Tropical Islands, Key Laboratory of Tropical Animal and Plant Ecology of Hainan Province, College of Life Sciences, Hainan Normal University, Haikou, 571158, China.
Key Laboratory of Tropical Translational Medicine of Ministry of Education, NHC Key Laboratory of Tropical Disease Control, School of Tropical Medicine, Hainan Medical University, Haikou, 571199, China.
Environ Sci Pollut Res Int. 2022 Jul;29(33):50832-50844. doi: 10.1007/s11356-022-19354-0. Epub 2022 Mar 3.
Chemical pollutants present a substantial threat to the survival of the green turtle (Chelonia mydas). In this study, the concentrations of 12 trace elements (TEs) in seawater, sediments, and green turtle forage and eggshells from the Xisha Islands in the South China Sea, along with their patterns of transfer and accumulation, were identified. The results revealed that the median TE concentrations in seawater and sediments were lower than the first-grade limit values of the national standard in China, indicating a low ecological risk. The concentrations (μg·g) of TEs in forage ranged from 0.05-0.69, 3.43-14.4, 157-2391, 27.9-124, 2.05-9.39, 0.30-9.78, 2.01-80.50, 0.18-5.76, 0.06-0.98, 2.00-18.4, 0.02-0.24, and 0.01-0.09 for Cr, Mn, Sr, Fe, Ni, Cu, Zn, Se, Cd, As, Pb, and Hg, respectively. Seawater, sediments, turtle forage, and eggshells exhibited different TE profiles, which were driven by Hg, Sr, Cr, and Pb in seawater and sediments; Fe and Ni in sediments; Cd and As in forage; and Zn, Se, and Cu in eggshells. The contents of Cu, Zn, and Se increased slightly with trophic level, indicating that they were transferred through dietary pathways. Although Cd and As appeared to bioaccumulate in green turtle forage, it was not transferred to their eggshells, which may be related to the excretion and metabolism process in the mother's body. Thus, eggshells may be a poor bioindicator for the exposure of female green turtles to these toxic elements.
化学污染物对绿海龟（蠵龟）的生存构成了重大威胁。在本研究中，对中国南海西沙群岛海水、沉积物、绿海龟食物及龟卵壳中12种微量元素（TEs）的浓度及其转移和积累模式进行了测定。结果表明，海水和沉积物中TEs的中位浓度低于中国国家标准的一级限值，表明生态风险较低。食物中TEs的浓度（μg·g）分别为：铬0.05 - 0.69、锰3.43 - 14.4、锶157 - 2391、铁27.9 - 124、镍2.05 - 9.39、铜0.30 - 9.78、锌2.01 - 80.50、硒0.18 - 5.76、镉0.06 - 0.98、砷2.00 - 18.4、铅0.02 - 0.24、汞0.01 - 0.09。海水、沉积物、海龟食物和龟卵壳呈现出不同的TEs分布特征，这是由海水和沉积物中的汞、锶、铬和铅；沉积物中的铁和镍；食物中的镉和砷；以及龟卵壳中的锌、硒和铜驱动的。铜、锌和硒的含量随营养级略有增加，表明它们是通过饮食途径转移的。尽管镉和砷似乎在绿海龟食物中生物累积，但并未转移到龟卵壳中，这可能与母体的排泄和代谢过程有关。因此，龟卵壳可能不是雌性绿海龟接触这些有毒元素的良好生物指示物。
