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\hypersetup{pdftitle={Investigation of Mercury Concentration as an Environmental Toxic Element at Muscle and Skin Textures of Zander Fish (Sander Lucioperca) in Caspian Sea},pdfauthor={Leila Taheri Azad, Abbas Esmaili Sari, Kamran Rezai Tavabe},pdfsubject={Tropentag 2010: Abstract},pdfkeywords={Caspian Sea, Health Standard          , mercury, Muscle, skin,, Zander fish},pdfpagemode=None,colorlinks=true}
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\parbox[b]{13.4cm}{\centering \large{\textbf{Tropentag, September 14-16, 2010, Zurich}}\\[1ex] \Large{``World Food System  ---\\A Contribution from Europe''\\[2ex]}}
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\begin{center}
\Large{\textbf{Investigation of Mercury Concentration as an Environmental Toxic Element at Muscle and Skin Textures of Zander Fish (Sander Lucioperca) in Caspian Sea\footnote{\textbf{Contact Address:} Leila Taheri Azad, Tarbiyat Modares University, Department of Environmental Science, 3814894383~Arak, Iran, \mbox{e-mail}: \email{ltaheriazad@yahoo.com}}\\[0.8ex]}}
\normalsize{\textsc{Leila Taheri Azad$^{1}$, Abbas Esmaili Sari$^{2}$, Kamran Rezai Tavabe$^{3}$}}
\end{center}
\begin{itemize*}
\item[]{\small{\textit{$^{1}$Tarbiyat Modares University, Department of Environmental Science, Iran}}}
\item[]{\small{\textit{$^{2}$Tarbiyat Modares University, Department of Environmental Science, Natural Recourses Faculty, }}}
\item[]{\small{\textit{$^{3}$University of Tehran, Department of Fishery, Iran}}}
\end{itemize*}
\index[author]{Taheri Azad, Leila}
\index[author]{Esmaili Sari, Abbas}
\index[author]{Rezai Tavabe, Kamran}
\begin{center}
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\textbf{Abstract}
\begin{abstract}
\normalsize{
Mercury is one of the toxic elements in environment that among the heavy metal contamination the most attention is on mercury and effect of it on human health and other lives was assessed. Since more than of \mbox{90\,\%} of methyl mercury accumulate in aquatic organism. Once in the aquatic ecosystems, part of the inorganic mercury can be microbiologically converted into methylmercury and taken up by aquatic organisms. Fish accumulate mercury directly from food and the surrounding water and can bioconcentrate large amounts of this metal. An evaluation of several studies of the critical body burden of mercury in fish suggests that whole body concentrations of 10---\unitfrac[20]{mg}{kg} could be lethal to fish, while whole body concentrations of 1---\unitfrac[5]{mg}{kg} could have chronic effects. The main aims of this present study were investigation of weight, age and generation factors influences on mercury bioaccumulation at muscle and skin textures of Zander fish and comparison of the mercury concentration at studied textures with universal standards level. For this purpose, at 2006 at western Caspian Sea shores (from Jefroud fishery station to Anzali wetland) 21 numbers Zander fish were obtained and then after biometry (measuring length, age and weight) and sex determination, the mercury concentration at studied textures by Advanced Mercury Analyzer 254 LECO apparatus were detected. Based on the results, the mercury concentration at muscle and skin (ppb in dry weight) was 0.097$\pm$0.014 and 0.035$\pm$0.007 respectively. The results showed significant differences between age and weight factors with mercury accumulation at studied texture ($p < 0.05$) while generation factor showed any significant differences on mercury concentration at the texture ($p < 0.05$). The comparison of the mercury bioaccumulation with universal standards threshold level (WHO, FAO and FDA) showed lower concentration than authorised level for mercury in fish.}

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\noindent \textbf{Keywords:} Caspian Sea, Health Standard          , mercury, Muscle, skin,, Zander fish
\index[key]{Caspian Sea}
\index[key]{Health!Standard          }
\index[key]{Mercury}
\index[key]{Muscle}
\index[key]{Skin,}
\index[key]{Zander fish}
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