The skin of Commerson's dolphins (Cephalorhynchus commersonii) as a biomonitor of mercury and selenium in Subantarctic waters.
The skin of bycaught Commerson's dolphins was tested for mercury (Hg) and selenium (Se) biomonitoring in Subantarctic environments. The correlation of levels detected in the skin with those found in internal tissues - lung, liver, kidney and muscle - was assessed to evaluate how skin represents internal Hg and Se distribution for monitoring purposes. Mercury in skin had a concentration range of 0.68-3.11 μg g(-1) dry weight (DW), while Se had a higher concentration range of 74.3-124.5 μg g(-1) DW. There was no significant correlation between selenium levels in any of the analyzed tissues. Thus, the skin selenium concentration did not reflect the tissular Se levels and did not provide information for biomonitoring. The lack of correlation is explained by the biological role of Se, provided that each tissue regulates Se levels according to physiological needs. However, the skin Hg level had significant positive correlation with the levels in internal tissues (ANOVA p<0.05), particularly with that of muscle (R(2)=0.79; ANOVA p=0.0008). Thus, this correlation permits the estimation of Hg content in muscle based on the multiplication of skin biopsy levels by a factor of 1.85. Mercury bioindication using skin biopsies is a non-lethal approach that allows screening of a large number of specimens with little disturbance and makes possible an adequate sampling strategy that produces statistically valid results in populations and study areas. The correlation between Hg levels in the skin and internal tissues supports the use of the epidermis of Commerson's dolphins for Hg biomonitoring in the waters of the Subantarctic, which is a poorly studied region regarding Hg levels, sources and processes.
Laboratorio de Ecología, Comportamiento y Mamíferos Marinos (LECyMM), División Mastozoología, Museo Argentino de Ciencias Naturales "Bernardino Rivadavia" (MACN-CONICET), Av. Ángel Gallardo 470, C1405DJR Buenos Aires, Argentina; Museo Acatushún de Aves y Mamíferos Marinos Australes, Sarmiento 44, 9410 Ushuaia, Tierra del Fuego, Argentina.
Iris
I
Cáceres-Saez
Museo Acatushún de Aves y Mamíferos Marinos Australes, Sarmiento 44, 9410 Ushuaia, Tierra del Fuego, Argentina; Centro Austral de Investigaciones Científicas (CADIC-CONICET), Houssay 200, V9410BFD Ushuaia, Tierra del Fuego, Argentina.
R Natalie P
RN
Goodall
Museo Acatushún de Aves y Mamíferos Marinos Australes, Sarmiento 44, 9410 Ushuaia, Tierra del Fuego, Argentina; Centro Austral de Investigaciones Científicas (CADIC-CONICET), Houssay 200, V9410BFD Ushuaia, Tierra del Fuego, Argentina.
Natalia A
NA
Dellabianca
Laboratorio de Ecología, Comportamiento y Mamíferos Marinos (LECyMM), División Mastozoología, Museo Argentino de Ciencias Naturales "Bernardino Rivadavia" (MACN-CONICET), Av. Ángel Gallardo 470, C1405DJR Buenos Aires, Argentina; Centro de Estudios Biomédicos, Biotecnológicos, Ambientales y Diagnóstico (CEBBAD), Fundación de Historia Natural Félix de Azara, Departamento de Ciencias Naturales y Antropología, Universidad Maimónides, Hidalgo 775, C1405BCK Buenos Aires, Argentina.
H Luis
HL
Cappozzo
Laboratorio de Análisis por Activación Neutrónica, Centro Atómico Bariloche-Comisión Nacional de Energía Atómica (CAB-CNEA), Av. E. Bustillo 9500, 8400 Bariloche, Argentina. Electronic address: ribeiro@cab.cnea.gov.ar.
Sergio
S
Ribeiro Guevara
D000818:Animals; D001118:Argentina; D004289:Dolphins / Q000378:metabolism*; D004784:Environmental Monitoring / Q000379:methods*; D007668:Kidney / Q000737:chemistry; D008099:Liver / Q000737:chemistry; D008628:Mercury / Q000032:analysis* / Q000493:pharmacokinetics; D009132:Muscles / Q000737:chemistry; D012643:Selenium / Q000032:analysis* / Q000493:pharmacokinetics; D012867:Skin / Q000737:chemistry*; D014018:Tissue Distribution; D014874:Water Pollutants, Chemical / Q000032:analysis* / Q000493:pharmacokinetics
D014874:Water Pollutants, Chemical; D008628:Mercury; D012643:Selenium
Marine environments; Mercury; Selenium; Skin biomonitoring; Small cetaceans; South Atlantic Ocean