Determination of total mercury in muscle, intestines, liver and kidney tissues of cormorant (Phalacrocorax carbo), great crested grebe (Podiceps cristatus) and Eurasian buzzard (Buteo buteo)

Abstract

The total mercury concentrations in four tissues (muscle, intestines, liver and kidney) of aquatic birds (cormorant - Phalacrocorax carbo and great crested grebe - Podiceps cristatus) and Eurasian buzzard (Buteo buteo) were determined by cold vapour atomic absorption spectrometry (CV-AAS) using an Advanced Mercury Analyser AMA 254. The results of the direct CV-AAS analyses of homogenised solid samples were in very good agreement with those obtained by CV-AFS and CV-AAS analyses after acid digestion. Mercury concentrations in the tested tissues of adult populations of great crested grebe and cormorant were nearly twice as high as in the Eurasian buzzard. Significantly higher mercury concentrations were found in the liver and kidney of the cormorant (7-times and 2-times, respectively) compared to great crested grebe. The highest mercury concentration (39.2 mg/kg DM) was found in liver of adult population of cormorant while the content of mercury in younger cormorants was approx. 6-times lower (5.8 mg/kg DM). The total mercury concentration in liver was 6-times higher (2-3-times in muscle and kidney) but 13-times lower then those of the cormorant population living in Japan (Tokyo, Lake Biwa) and in the United States (Nevada, Carson River), respectively.