Influence of persistent organic pollutants on the endocrine stress response in free-living and captive red kites (Milvus milvus)

• Published in: Environmental pollution (1987) Vol. 242; no. Pt A; pp. 329 - 337
• Main Authors: Monclús, Laura, Ballesteros-Cano, Rubèn, De La Puente, Javier, Lacorte, Silvia, Lopez-Bejar, Manel
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01.11.2018
• Subjects: Corticosterone; DDE (pesticide); DDT (pesticide); DDTs; DHEA; endocrine system; Feathers; hexachlorobenzene; migratory behavior; Milvus milvus; Northern European region; PCBs; persistent organic pollutants; polychlorinated biphenyls; prasterone; Raptors; Spain; stress response; Northern European region; Spain; DHEA; DDTs; Raptors; Feathers; PCBs; Corticosterone
• ISSN: 0269-7491; 1873-6424; 1873-6424
• DOI: 10.1016/j.envpol.2018.06.086

Persistent organic pollutants (POPs) have the potential to impair the endocrine regulation of organisms and alter their ability to respond to environmental changes. We studied whether polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) affected the endocrine regulation of free-living and captive red kites (Milvus milvus) through studying the dynamics of corticosterone (CORT) and dehydroepiandrosterone (DHEA). We sampled migratory free-living kites coming from northern Europe and captive kites born in a rehabilitation center in Spain. We used body feathers from the interscapular region as a minimally-invasive and integrative matrix. The most abundant compound detected in free-living kites was 4,4′-dichlorodiphenyldichloroethylene (4,4′-DDE; 6.10 ± 1.56 ng g−1 dw feather) followed by CB-153 (3.10 ± 0.63 ng g−1 dw feather) and CB-180 (2.43 ± 1.08 ng g−1 dw feather). In captive kites, the most abundant compounds were 4,4′-dichlorodyphenyltrichloroethane (4,4′-DDT; 2.38 ± 1.30 ng g−1 dw feather), CB-153 (2.15 ± 0.47 ng g−1 dw feather) and hexachlorobenzene (HCB; 2.03 ± 0.45 ng g−1 dw feather) at similar concentrations. Free-living kites showed higher levels of 4,4′-DDE and CB-180 in comparison to captive kites. Age influenced HCB and CB-101 levels, whereas body mass was inversely related to CB-180 and 4,4′-DDT. Interestingly, captive kites showed a ratio DDT/DDE higher than 1 suggesting a relatively recent exposure of DDT, in contrast to free-living kites. Regarding hormonal levels, free-living kites showed higher levels of CORT (3.30 ± 0.22 pg mm−1 feather) than captive (2.40 ± 0.16 pg mm−1 feather), reflecting higher allostatic load. In addition, a positive association between PCBs and DDTs and adrenal hormones was found in free-living kites, suggesting an increase of CORT as a response of the endocrine system to cope with stressors and a subsequent elevation of DHEA to ameliorate the potential negative effects that high CORT levels could cause to the organism. [Display omitted] •First assessment of dehydroepiandrosterone (DHEA) in feathers.•Study of the relationship between DHEA and corticosterone (CORT) levels in feathers.•Different hormone levels were observed between free-living and captive kites.•PCBs and DDTs were positively correlated to CORT and DHEA in free-living kites.•Further research is needed focusing on the mechanism of interaction with HPA axis. Positive relationship between PCBs and DDTs and adrenal hormones in free-living red kites.