Mercury accumulation, speciation, and temporal trends in Atlantic Stingrays (Hypanus sabinus)

Mercury (Hg) deposited into aquatic sediments can be converted into the more toxic methylmercury (MeHg) by microbial activity. Atlantic stingrays (Hypanus sabinus) are an estuarine and nearshore species found in coastal regions of the western North Atlantic, occurring in multiple habitat types, and...

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Veröffentlicht in:Ecotoxicology (London, England). - 1992. - 28(2019), 3 vom: 13. Apr., Seite 251-260
1. Verfasser: Soulen, Brianne K (VerfasserIn)
Weitere Verfasser: Adams, Douglas H, Roberts, Aaron P
Format: Online-Aufsatz
Sprache:English
Veröffentlicht: 2019
Zugriff auf das übergeordnete Werk:Ecotoxicology (London, England)
Schlagworte:Journal Article Elasmobranch Florida Methylmercury Temporal mercury trends Total mercury Methylmercury Compounds Water Pollutants, Chemical Mercury FXS1BY2PGL
Beschreibung
Zusammenfassung:Mercury (Hg) deposited into aquatic sediments can be converted into the more toxic methylmercury (MeHg) by microbial activity. Atlantic stingrays (Hypanus sabinus) are an estuarine and nearshore species found in coastal regions of the western North Atlantic, occurring in multiple habitat types, and feeding mainly on benthic invertebrates. Mercury dynamics and speciation in stingrays have not been well examined. This study quantified total Hg and Hg species (Hg (II) and MeHg) in Atlantic stingrays sampled from Florida's Indian River Lagoon (IRL) from 2012 to 2013. Tissues (muscle and liver) collected from 29 stingrays were lyophilized and homogenized before being analyzed using a direct mercury analyzer. Concentrations of total Hg in muscle were positively related to stingray disk width, but concentrations in liver were not. Mean (±SD) total Hg in muscle (0.56 ± 0.30 mg/kg dw) was significantly higher than mean total Hg in liver (0.23 ± 0.19 mg/kg dw). Within liver tissue, percent MeHg (of total Hg) ranged from 31 to 99%. The ratio between total Hg in liver and total Hg in muscle was <1 for nearly all individuals, suggesting a lack of active hepatic demethylation and sequestration mechanisms. Concentrations of Hg in IRL Atlantic stingrays fall below concentrations known to result in direct toxicity to fishes; however, effects thresholds are not well understood for elasmobranchs. Comparisons of Hg concentrations in IRL Atlantic stingrays sampled previously (37 individuals in 1994) indicate that total Hg concentrations in muscle of Atlantic stingrays have decreased over the past two decades, suggesting a reduction in the bioavailable Hg in the IRL ecosystem
Beschreibung:Date Completed 01.07.2019
Date Revised 30.09.2020
published: Print-Electronic
ErratumIn: Ecotoxicology. 2019 Apr 15;:. - PMID 30989483
Citation Status MEDLINE
ISSN:1573-3017
DOI:10.1007/s10646-018-02014-w