Mercury concentrations in blood, brain and muscle tissues of coastal and pelagic birds from northeastern Canada

• Published in: Ecotoxicology and environmental safety 2018-08, Vol.157, p.424-430
• Main Authors: Mallory, Mark L., Provencher, Jennifer F., Robertson, Gregory J., Braune, Birgit M., Holland, Erika R., Klapstein, Sara, Stevens, Kelly, O’Driscoll, Nelson J.
• Format: Article
• Language: English
• Subjects: Animals; Aquatic birds; Birds - blood; Birds - classification; Brain Chemistry; Canada; Contaminant; Environmental Monitoring; Food Chain; Mercury; Mercury - blood; Muscle, Skeletal - chemistry; Neurotoxicity; Sublethal effects; Water Pollutants, Chemical - blood
• ISSN: 0147-6513; 1090-2414
• DOI: 10.1016/j.ecoenv.2018.04.004

Mercury (Hg) is a toxic element which has increased in marine environments for more than a century, due largely to anthropogenic activities, and biomagnifies in food chains to harmful levels in some top predators like waterfowl and seabirds. We analysed total mercury (THg) concentrations in blood, brain and muscle tissue from healthy specimens of 13 coastal and pelagic bird species from eastern and northern Canada to provide a baseline on current concentrations, especially for brain concentrations which are highly underrepresented in the literature. We also examined within and among tissues relationships of THg concentrations within individuals. THg concentrations were generally higher in pelagic species and scavenging gulls, when compared to coastal waterfowl. Brain and muscle tissue had similar concentrations of THg in the birds examined, but both of these tissues had lower concentrations that those found in blood. Our results, and that of a previous study, suggest that body condition has a large influence on blood THg concentrations and should be considered when using blood as a sampling medium. Many of the species we examined had tissue THg above levels known to cause deleterious, sublethal effects in some species. •Total mercury (THg) was sampled in blood, brain and muscle tissue of 13 species of wild, apparently healthy marine birds.•Muscle and brain THg concentrations approximated a 1:1 ratio, whereas blood THg values were more variable.•Gulls and pelagic seabirds had higher THg concentrations that coastal waterfowl.