Apex predators are characterized by high levels of biomagnifying organohalogenated contaminants (OHCs) which have been found to induce detrimental health effects in wildlife, such as immune system impairment. The leukocyte coping capacity (LCC) assay is a functional real-time measure of an innate immune response essential in pathogen resistance, known as the respiratory burst. The current study suggests the novel use of this tool to test whether OHCs impair the innate immune system of a sentinel top predator, the white-tailed eagle (Haliaeetus albicilla; WTE). The LCC analysis was performed in the field on WTE nestlings (n = 84) from northern Norway over two breeding seasons. Poly- and perfluoroalkyl substances (PFAS) dominated the total OHC load, surpassing the levels of legacy organochlorines. In addition, we detected significant negative correlations between concentrations of all polychlorinated biphenyls, p,p′-dichlorodiphenyldichloroethylene, perfluorohexane sulfonic acid and long-chain perfluorocarboxylic acids and the LCC of WTE nestlings. Based on our current findings reflecting a potential negative effect of both emerging and legacy OHCs on innate immune capacity, we suggest LCC to be a relevant and accessible test expanding the ecotoxicological toolbox to assess sub-lethal effects of OHCs in apex avian wildlife.

Apex捕食者的特征是高水平的生物放大有机卤代污染物（OHC），已发现它们会在野生生物中引起有害的健康影响，例如免疫系统受损。白细胞应对能力（LCC）分析是功能性实时测量，对病原体抵抗力至关重要的先天免疫应答（称为呼吸爆发）。当前的研究表明，该工具的新颖用途在于测试OHC是否会损害前哨捕食者白尾鹰（Haliaeetus albicilla ; WTE）的先天免疫系统。LCC分析是在野外对WTE雏鸟（n = 84）来自挪威北部的两个繁殖季节。聚和全氟烷基物质（PFAS）在OHC的总负荷中占主导地位，超过了传统有机氯的水平。此外，我们检测到所有多氯联苯，p，p'-二氯二苯基二氯乙烯，全氟己烷磺酸和长链全氟羧酸的浓度与WTE雏鸡的LCC之间存在显着的负相关。根据我们目前的发现，反映新兴和旧式OHC对先天免疫能力的潜在负面影响，我们建议LCC是一项相关且可访问的测试，可扩展生态毒理学工具箱，以评估OHC对禽类先天野生动物的亚致死作用。