Methyl and total mercury found in two man-made Amazonian Reservoirs

Abstract

Metilmercúrio (MeHg) e mercúrio total (Hg) foram determinados em amostras de água e peixe coletadas em dois reservatórios da Amazônia Brasileira, que apresentam diferentes características limnológicas e ecológicas. As amostras de água de Tucuruí, reservatório mesotrófico com águas claras, apresentaram a concentração de Hg (12,7 ± 8,4 ng L ), an oligotrophic reservoir with black water. Neither Cichla spp. (piscivorous fish), nor Geophagus surinamensis (omnivorous fish) presented significant differences in length-normalized concentrations of MeHg and Hg in muscle, between both reservoirs. MeHg and Hg increased with body weight and standard length of Cichla spp., and also with the trophic level on the food chain. The Hg bioconcentration factor (BCF) increased with the trophic level of the fish, from the omnivorous (10 3 ) to piscivorous fish (10 4 ). Fish from Balbina, an ecosystem naturally rich in dissolved organic matter, presented the highest BCF. Not only the different limnological and ecological characteristics but also the feeding habits seem to influence the mercury concentration in fish.

Evaluation of the Concentration of Cu, Zn, Pb and Cr in Different Fish Species from the São Gonçalo Channel in Pelotas-RS, Brazil

“…It may also cause anemia and in some cases lead to cancer. 10 The quantification of metals in fish tissue is usually carried out by atomic spectrometry techniques, such as flame atomic absorption spectrometry (F AAS); 4,9,[13][14][15][16] graphite furnace atomic spectrometry (GF AAS); 1,9,14,[17][18][19][20][21][22] inductively coupled plasma mass spectrometry (ICP-MS); 6,[23][24][25][26][27][28] inductively coupled plasma optical emission spectrometry (ICP OES) 6,23,29,30 or cold vapor atomic absorption spectrometry (CV AAS). 1,11,16 In general, for the determination of metals such as Cu, Zn, Pb and Cr in fish tissue samples using atomic spectrometry techniques, the sample must be in acid solution.…”

“…1,11,16 In general, for the determination of metals such as Cu, Zn, Pb and Cr in fish tissue samples using atomic spectrometry techniques, the sample must be in acid solution. The use of acid decomposition in open systems using digestion blocks; [15][16][17][18]29 in closed systems using the microwave oven 1,4,6,9,11,13,23,25,27,31 or by dry ashing 22 are widely used for this purpose. However, some of these systems present risk of contamination and analyte losses through volatilization or adsorption when open flasks are used.…”

Analytical chemistry in Brazil: healthy and growing

“…93 The most frequently studied sample is water, mainly due to its ability to disseminate diseases and several aspects of contaminants are reported at the water/air and soil/air interfaces. 94 Kehrig et al 95 determined methylmercury (MeHg) and total Hg in water and fish samples from two reservoirs within Brazilian Amazon and observed that the bioconcentration factor (BCF) is higher in ecosystem rich in dissolved organic matter. Santos et al 96 coupled HPLC and ICP-MS for determination of organic and inorganic Hg species in water samples.…”

Estratégias metaloproteômicas na investigação de biomarcadores de mercúrio em amostras de tecido muscular de tucunarés

“…Contudo, há uma crescente migração para os centros urbanos devido, sobretudo, à ocupação do solo pela pecuária extensiva e construção de grandes empreendimentos hidrelétricos (QUEIROZ et al, 2012). Além disso, essas duas atividades também contribuem com o aporte do mercúrio no ambiente (KEHRIG et al, 2009). …”