Oil-related contaminants in Arctic seabirds

We sampled four seabird species [black guillemot - (Cepphus grylle; n = 20), thick-billed murre (Uria lomvia; n = 30), black-legged kittiwake (Rissa tridactyla; n = 20) and northern fulmar (Fulmarus glacialis; n = 30)] in the Baffin Bay-Davis Strait region; an area where natural oil and gas seeps are present but lacking any large scale oil and gas projects. Inuit hunters collected the seabirds in Qaqulluit National Wildlife Area in July 2018 off the southeast corner of Baffin Island. Liver tissue of each bird was then analyzed for oil-related contaminants (Polycyclic Aromatic Compounds; PACs) and trace elements. We found detectable levels of PACs and several trace elements in all species examined. Northern fulmars had the highest concentrations of parent and alkylated PACs, which differed significantly from the other species. Alkylated PACs were higher than parent compounds in all four seabird species examined, with fulmars and murres having the highest levels detected. Overall, PAC concentrations in the seabird species examined were similar to PAC concentrations for other bird species examined in regions with more industrialization. Metabolomics analysis revealed that thick-billed murres are more prone to oxidative stress when compared to black guillemots. These findings provide data for assessing the current oil-related contaminant exposure of biota in the region. As well, they provide background levels for the region at a time when shipping activity is relatively low, which can used for future comparisons following expected increases in shipping and oil and gas activities.

本研究于巴芬湾-戴维斯海峡区域（Baffin Bay-Davis Strait region）采样了四种海鸟物种：黑海鸠（Cepphus grylle，n=20）、厚嘴海鸦（Uria lomvia，n=30）、黑脚三趾鸥（Rissa tridactyla，n=20）以及北方管鼻鹱（Fulmarus glacialis，n=30）。该区域存在天然油气渗漏，但尚无大规模油气开发项目。2018年7月，因纽特猎人于巴芬岛（Baffin Island）东南角外的卡库卢伊特国家野生动物保护区（Qaqulluit National Wildlife Area）采集了上述海鸟。随后对每只海鸟的肝脏组织开展分析，检测其中的石油类污染物——多环芳烃化合物（Polycyclic Aromatic Compounds, PACs）与微量元素。本研究在所有受试海鸟物种中均检出了PACs与多种微量元素。其中，北方管鼻鹱的母体型与烷基化PACs浓度均为四种受试物种中最高，且与其余三个物种存在显著差异。所有受试海鸟物种的烷基化PACs浓度均高于母体型PACs，北方管鼻鹱与厚嘴海鸦的检出浓度最高。总体而言，本研究中受试海鸟的PACs浓度，与工业化程度更高区域内其他受试鸟类的PACs浓度水平相近。代谢组学分析结果显示，相较于黑海鸠，厚嘴海鸦更易发生氧化应激。本研究结果可为评估该区域当前生物群落的石油类污染物暴露水平提供数据支撑。同时，在当前航运活动相对较低的背景下，本研究数据可为该区域提供本底浓度水平，可用于未来航运与油气活动预期增加后的对比评估。