Predicting consequences of POP-induced disruption of blubber glucose uptake, mass gain rate and thyroid hormone levels for weaning mass in grey seal pups
[en] Persistent organic pollutants (POPs) are endocrine disruptors that alter adipose tissue development, regulation and function. Top marine predators are particularly vulnerable because they possess large fat stores that accumulate POPs. However, links between endocrine or adipose tissue function disruption and whole animal energetics have rarely been investigated. We predicted the impact of alterations to blubber metabolic characteristics and circulating thyroid hormone (TH) levels associated with polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), and organochlorine pesticides (OCPs) on suckling mass gain and weaning mass in wild grey seal pups. Glucose uptake by inner blubber was a strong predictor of whole animal mass gain rate, which in turn, resulted in heavier weaning mass. Weaning mass was predicted to increase by 3.7 ± 1.59 (sem) %, through increased mass gain rate, in the absence of the previously reported suppressive effect of dioxin-like PCB (DL-PCBs) on blubber glucose uptake. PBDEs were, conversely, associated with faster mass gain. Alleviation of this effect was predicted to reduce weaning mass by 6.02 ± 1.86% (sem). To better predict POPs effects on energy balance, it is crucial to determine if and how PBDEs promote mass gain in grey seal pups. Weaning mass was negatively related to total T3 (TT3) levels. A 20% (range = 9.3–31.7%) reduction in TT3 by DL-PCBs partially overcame the effect of DL-PCB -mediated reduction in blubber glucose uptake. Overall, DL-PCBs were thus predicted to reduce weaning mass by 1.86 ± 1.60%. Organohalogen impacts on whole-animal energy balance in grey seal pups appear to partially offset each other through opposing effects on different mechanisms. POP effects were generally minor, but the largest POP-induced reductions in weaning mass were predicted to occur in pups that were already small. Since weaning mass is positively related to first-year survival, POPs may disproportionately affect smaller individuals, and could continue to have population-level impacts even when levels are relatively low compared to historical values. Our findings show how in vitro experiments combined with measurements in vivo can help elucidate mechanisms that underpin energy balance regulation and help to quantify the magnitude of disruptive effects by contaminants and other stressors in wildlife.
Research Center/Unit :
CART - Centre Interfacultaire d'Analyse des Résidus en Traces - ULiège
Disciplines :
Chemistry Aquatic sciences & oceanology
Author, co-author :
Bennett, Kimberley; Abertay University > School of Applied Sciences > Division of Health Sciences
Robinson, Kelly; University of St Andrews > Scottish Oceans Institute > Sea Mammal Research Unit
Armsrtong, Holly; Abertay University > School of Applied Sciences > Division of Health Sciences
Moss, Simon; University of St Andrews > Scottish Oceans Institute > Sea Mammal Research Unit
Scholl, Georges ; Université de Liège - ULiège > Département de chimie (sciences) > Center for Analytical Research and Technology (CART)
Tranganida, Alexandra; Abertay University > School of Applied Sciences > Division of Health Sciences
Eppe, Gauthier ; Université de Liège - ULiège > Département de chimie (sciences) > Chimie analytique inorganique
Thomé, Jean-Pierre ; Université de Liège - ULiège > Département de Biologie, Ecologie et Evolution > Ecologie animale et écotoxicologie
Debier, Cathy; Université Catholique de Louvain - UCL > Louvain Institute of Biomolecular Science and Technology
Hall, Ailsa; University of St Andrews > Scottish Oceans Institute > Sea Mammal Research Unit
Language :
English
Title :
Predicting consequences of POP-induced disruption of blubber glucose uptake, mass gain rate and thyroid hormone levels for weaning mass in grey seal pups
Publication date :
July 2021
Journal title :
Environment International
ISSN :
0160-4120
eISSN :
1873-6750
Publisher :
Elsevier, United Kingdom
Volume :
152
Peer reviewed :
Peer Reviewed verified by ORBi
Name of the research project :
Pollutants, Hormones and Adipose Tissue in Seals - PHATS
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