宽吻海豚(Tursiopstruncatus)是世界海洋中的基石和前哨物种。我们研究了全氟烷基和多氟烷基物质(PFAS)与其应力轴之间的相关性。我们调查了12种不同PFAS变体的血浆生物标志物与三种皮质醇库之间的关联(总计,绑定,并且免费)在查尔斯顿河口水域的野生T.truncatus中,南卡罗来纳州(n=115)和印度河泻湖,佛罗里达州(n=178),2003年至2006年,2010年至2013年和2015年。以前曾报道过这些海豚的所有PFAS和总皮质醇水平;以前没有报道过结合皮质醇水平和游离皮质醇计算。我们测试了无效假设,即每个PFAS的水平与每个皮质醇池的水平无关。当全氟辛烷磺酸时,游离皮质醇水平较低,PFOA,和PFHxS生物标志物水平较高,但当PFTriA较高时游离皮质醇水平较高。当PFDA较高时,结合的皮质醇水平较高,PFDoDA,PFDS,PFTeA,和PFUnDA生物标志物。当PFOA较低时,总皮质醇较高,但是当PFDA时,总皮质醇更高,PFDoDA,PFTeA,PFTriA较高。其他分析表明性别和年龄趋势,以及协变量碳链长度和PFAS类别的影响的异质性。虽然这是一项横断面观察研究,因此,可以反映皮质醇对PFAS毒物代谢动力学的影响,这些相关性表明PFAS会影响T.truncatus的应力轴。然而,如果PFAS确实影响了海豚的应力轴,它是特定的化学结构,并且可能会对各个皮质醇池产生不同的影响。对这些海豚进行长期研究并将它们与没有或很少接触PFAS的种群进行比较至关重要。
Bottlenose dolphins (Tursiops truncatus) are keystone and sentinel species in the world\'s oceans. We studied correlations between per- and polyfluoroalkyl substances (PFAS) and their stress axis. We investigated associations between plasma biomarkers of 12 different PFAS variants and three cortisol pools (total, bound, and free) in wild T. truncatus from estuarine waters of Charleston, South Carolina (n = 115) and Indian River Lagoon, Florida (n = 178) from 2003 to 2006, 2010-2013, and 2015. All PFAS and total cortisol levels for these dolphins were previously reported; bound cortisol levels and free cortisol calculations have not been previously reported. We tested null hypotheses that levels of each PFAS were not correlated with those of each cortisol pool. Free cortisol levels were lower when PFOS, PFOA, and PFHxS biomarker levels were higher, but free cortisol levels were higher when PFTriA was higher. Bound cortisol levels were higher when there were higher PFDA, PFDoDA, PFDS, PFTeA, and PFUnDA biomarkers. Total cortisol was higher when PFOA was lower, but total cortisol was higher when PFDA, PFDoDA, PFTeA, and PFTriA were higher. Additional analyses indicated sex and age trends, as well as heterogeneity of effects from the covariates carbon chain length and PFAS class. Although this is a cross-sectional observational study and, therefore, could reflect cortisol impacts on PFAS toxicokinetics, these correlations are suggestive that PFAS impacts the stress axis in T. truncatus. However, if PFAS do impact the stress axis of dolphins, it is specific to the chemical structure, and could affect the individual pools of cortisol differently. It is critical to conduct long-term studies on these dolphins and to compare them to populations that have no or little expose to PFAS.