Mercury exposure and neurochemical impacts in bald eagles across several Great Lakes states.
Ecotoxicology
; 20(7): 1669-76, 2011 Oct.
Article
en En
| MEDLINE
| ID: mdl-21735125
ABSTRACT
In this study, we assessed mercury (Hg) exposure in several tissues (brain, liver, and breast and primary feathers) in bald eagles (Haliaeetus leucocephalus) collected from across five Great Lakes states (Iowa, Michigan, Minnesota, Ohio, and Wisconsin) between 2002-2010, and assessed relationships between brain Hg and neurochemical receptors (NMDA and GABA(A)) and enzymes (glutamine synthetase (GS) and glutamic acid decarboxylase (GAD)). Brain total Hg (THg) levels (dry weight basis) averaged 2.80 µg/g (range 0.2-34.01), and levels were highest in Michigan birds. THg levels in liver (r(p) = 0.805) and breast feathers (r(p) = 0.611) significantly correlated with those in brain. Brain Hg was not associated with binding to the GABA(A) receptor. Brain THg and inorganic Hg (IHg) were significantly positively correlated with GS activity (THg r(p) = 0.190; IHg r(p) = 0.188) and negatively correlated with NMDA receptor levels (THg r(p) = -0245; IHg r(p) = -0.282), and IHg was negatively correlated with GAD activity (r(s) = -0.196). We also report upon Hg demethylation and relationships between Hg and Se in brain and liver. These results suggest that bald eagles in the Great Lakes region are exposed to Hg at levels capable of causing subclinical neurological damage, and that when tissue burdens are related to proposed avian thresholds approximately 14-27% of eagles studied here may be at risk.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Contaminantes Químicos del Agua
/
Águilas
/
Exposición a Riesgos Ambientales
/
Mercurio
Límite:
Animals
País/Región como asunto:
America do norte
Idioma:
En
Revista:
Ecotoxicology
Asunto de la revista:
SAUDE AMBIENTAL
/
TOXICOLOGIA
Año:
2011
Tipo del documento:
Article
País de afiliación:
Estados Unidos