FISH SAMPLES AS BIOINDICATOR OF ENVIRONMENTAL QUALITY: SYNCHROTRON RADIATION TOTAL REFLECTION X-RAY FLUORESCENCE ANALYSIS (SR-TXRF)

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1 5 International Nuclear Atlantic Conference - INAC 5 Santos, SP, Brazil, August 8 to September, 5 ASSOCIAÇÃO BRASILEIRA DE ENERGIA NUCLEAR - ABEN ISBN: FISH SAMPLES AS BIOINDICATOR OF ENVIRONMENTAL QUALITY: SYNCHROTRON RADIATION TOTAL REFLECTION X-RAY FLUORESCENCE ANALYSIS (SR-TXRF) Ana Elisa Sirito de Vives 1, Silvana Moreira, Sandra Maria Boscolo Brienza 3, Orghêda Luiza Araújo Domingues Zucchi 4 and Virgilio Franco do Nascimento Filho 5 1 Faculdade de Engenharia, Arquitetura e Urbanismo Universidade Metodista de Piracicaba Rodovia Santa Bárbara D Oeste/Iracemápolis, km Santa Bárbara D Oeste, SP aesvives@unimep.br Faculdade de Engenharia, Arquitetura e Urbanismo Universidade Estadual de Campinas Caixa Postal Campinas, SP Silvana@fec.unicamp.br 3 Faculdade de Ciências Matemáticas, da Natureza e de Tecnologia da Informação Universidade Metodista de Piracicaba Rodovia do Açúcar, km Piracicaba, SP sbrienza@unimep.br 4 Faculdade de Ciências Farmacêuticas de Ribeirão Preto Universidade de São Paulo Avenida Café s/n Ribeirão Preto, SP olzucchi@fcfrp.usp.br 5 Centro de Energia Nuclear na Agricultura Universidade de São Paulo Avenida Centenário, Piracicaba, SP virgilio@cena.usp.br ABSTRACT In this study fish were used as bioindicators of environmental contamination. The species were collected in Piracicaba River, São Paulo state, Brazil and the toxic elements concentrations were determined in muscle tissue and viscus (liver, intestine and stomach) by Synchrotron Radiation Total Reflection X-Ray Fluorescence Analysis (SR-TXRF). Were determined the elements Ti, Cr, Mn, Fe, Ni,, and Ba. The results were compared with values established by Brazilian Legislation for general food. The elements concentrations evidenced potential risk to human health and environmental quality alteration of the studied area. The measurements were realized at the Laboratório Nacional de Luz Síncrotron (LNLS) located in Campinas, São Paulo State, Brazil. 1. INTRODUCTION The basin of the Piracicaba River is an important industrial and agricultural pole. It presents more than 9% of the area in São Paulo State and it concentrates great problems of use and

2 control of the water resources and serious problems of contamination for several pollutants. In the last years the Company of Basic Sanitation of São Paulo State/Regional Piracicaba CETESB, have been reported elevated concentrations of metals of toxicological interest in several points of the basin. These results came of water samples, turning the problem still more preoccupying, because, it is known thoroughly that the metals are quickly absorbed for the particulate material in suspension and, consequently, to the sediment deposited in the bed of the rivers, lakes and dams. Therefore, these compartments should present elevated concentrations of metals, however, these data are not very well known. Another unknown point is with relationship to the accumulation of metals along the trophyc chain, extremely important fact, once the population feeds of aquatic organisms. The value of biological methods to monitor metals in atmosphere of fresh water has been considered of great value, offering an economic and sensitive way of analysis. The fish are useful organisms in the study of contamination for metals, because besides they explore the different levels trophycs of the aquatic ecosystem, they move freely, exploring all the areas of a micro basin [1]. Considering the techniques of elementary analysis, the Synchrotron Radiation Total Reflection X-ray Fluorescence analysis (SR-TXRF) may be considered highly qualified to identify and quantify inorganic elements in different matrices. This technique constitutes a fast method for multielemental analysis that permits to perform simultaneously qualitative and quantitative analysis of elements of a wide range of atomic number and concentration..1. Biological Samples. MATERIALS AND METHODS In order to obtain a representative sample, were captured four species of fish most consumed in the study area, with alimentary regime and area of different lives: Hypostomus punctatus ( Cascudo ) and Prochilodus lineatus ( Corumbatá ), species that live in the bottom of the river, Oreochromis niloticus ( Tilápia ) and Pimelodus maculatus ( Mandi ), species that live in the surface. The fish samples were collected in the Piracicaba River, São Paulo State. The fishes were obtained directly of the local fishermen. For samples decomposition. g were weighted "in natura" and the digestion procedure was made with nitric acid and hydrogen peroxide []. The digestion was made in muscle tissue and viscus (liver, intestine and stomach). For Hypostomus punctatus ( Cascudo ) specie it was not possible to separate the viscus samples in liver, intestine and stomach. The extracts obtained in the digestion procedures were prepared for analysis by SR-TXRF... Instrumentation The experiments were carried out in the X-ray fluorescence station of the XRF beamline installed at the Laboratório Nacional de Luz Síncrotron (LNLS), located in Campinas city, São Paulo State, Brazil. For calibration of the system was employed standard solutions with well-known elements at different concentrations (4.5 to 55.5 µg.ml -1 ) in which it was added the element Ga as internal standard. For samples excitation a polychromatic beam with energy range 4- kev and with mm width and 1 mm height operating under total INAC 5, Santos, SP, Brazil.

3 reflection conditions was used. For the detection of the characteristics X-Ray was used a semiconductor Si(Li) detector. 3. RESULTS AND DISCUSSION 3.1. Calibration of the system and quantitative analysis using TXRF The standards solutions were irradiated by seconds in way to obtain the energy spectra of the characteristic X-rays and with them the calibration of the system denominated relative sensitivities. The equations 1 and are the relative sensitivities curve for K series and L series, respectively. The samples were irradiated for 1 s and using the results obtained for the relative sensitivities, the concentrations of the elements of interest were determined (Tables 1 to 4) [3]. ln Si = Zi. 358 Z i. 77 Z 3 i ( R = ) (1) ln Si = Z i. 44 Z 3 i ( R = ) () The analyzed elements become separated in two categories: (1) essentials and microcontaminants simultaneously: chromium, manganese, iron, nickel, copper and zinc and () environmental micro-contaminants: titanium and barium. The figures 1 to 4 shows the concentration of Cr, and considered of larger damage to the human health. In the figure 3 the Cr concentration is divided by a factor of 1 (intestine sample) and a factor 1 (stomach sample) for "Corumbatá" species and for "Mandi" species by a factor 1 for musculature sample. Table 1. Concentration of metals in Hypostomus punctatus ( Cascudo ) samples Element Liver Viscus Musculature Ti Cr Mn Fe nd Ba In order to evaluate the level of contamination in the studied area and the risks to human health by ingestion of fish contaminated, we adopted values established by Brazilian legislation for food in general, considering that there are not established limits of tolerance for fish. With relationship to elements Cr, Ni, and, the limits of legislation are: and 5 mg kg -1, respectively. For the elements manganese and iron we took as reference the values of the average chemical composition of some feeds such as rice, bean, orange, banana and others. The ranges of these values are 6 until 1 µg.g -1 and 1 until 7 µg.g -1, respectively [4, 5, 6]. INAC 5, Santos, SP, Brazil.

4 Table. Concentration of metals in Oreochromis niloticus ( Tilápia ) samples Element Liver Intestine Stomach Musculature Ti Cr.18 nd.9.4 Mn Fe Ba Table 3. Concentration of metals in Prochilodus lineatus ( Corumbatá ) samples Element Liver Intestine Stomach Musculature Ti nd Cr nd Mn nd Fe Ni nd nd Ba Table 4. Concentration of metals in Pimelodus maculatus ( Mandi ) samples Element Liver Intestine Stomach Musculature Ti Cr nd 1.55 Mn nd Fe Ni nd Ba In musculature samples, the element Ni was only determined in the species Pimelodus maculatus ("Mandi"). The measured concentration was four times superior to the reference value. In this same sample kind, the concentration of the elements and were below the reference value for all analyzed species. INAC 5, Santos, SP, Brazil.

5 For the element Cr it was possible to verify that the concentration determined in musculature samples were above the reference values for the species Hypostomus punctatus ( Cascudo ), Prochilodus lineatus ( Corumbatá ) and Pimelodus maculatus ( Mandi ). For the last species the Cr concentration measured was a hundred times larger than reference values. In this way, the consumption of these fish species is not recommended. In order to evaluate the environmental quality, specific organs, like liver, are useful. In liver samples, and Cr elements were above of reference values for the species "Cascudo" and "Tilápia, which live in the surface, and for the species, "Cascudo", "Tilápia" and "Mandi", respectively. Other organs, like stomach and intestine, may be used for indicating the local contamination in smaller degree than liver samples. For the species analyzed the concentration of the Cr and, in general, were above of reference values, while for the element it was verified for the species "Cascudo" (viscus sample) and "Corumbatá" (intestine and stomach samples). The concentration found for these elements indicated that there is alteration of the environmental quality of the local. The highest concentrations determined to Mn and Fe were obtained in viscus samples of Corumbatá species, with values sixty and two hundred times, respectively, higher than the recomended values (Table 3). There are not values in the list of reference for evaluation of the contamination by Ti and Ba. In this way, only comparisons around the concentration of these elements were made. The biggest concentrations for these elements were obtained in viscus samples for all analyzed species. It can also be verified that for the species that live in the bottom of the rivers, the concentrations were higher, reaching in some cases, values a thousand times higher than those determined in musculature samples. Cascudo Tilápia Corumbatá Mandi Cascudo Tilápia Corumbatá Mandi Liver samples Musculature samples Figure 1. Concentration of and in fish samples Tilápia Corumbatá Mandi Tilápia Corumbatá Mandi Intestine samples Stomach samples Figure. Concentration of and in Tilápia, Corunbatá and Mandi species INAC 5, Santos, SP, Brazil.

6 1,,9,6,3, Tilápia Corumbatá Liver Intestine Stomach Musculature Samples Mandi Figure 3. Concentration of Cr in Tilápia, Corunbatá and Mandi species Cascudo Cr Viscus samples Figure 4. Concentrations of Cr, and in Cascudo species 6. CONCLUSIONS The concentrations of the some elements detected are evidence that there is potential risk to human health and that it is necessary to take emergency steps aiming to minimize the ingestion of species captured. The concentration found for the elements indicated that there is alteration of the environmental quality in the area studied and that is necessary to monitor and identity the sources of pollutants. The procedure adopted in this study is appropriate for investigation of the sanitary quality of the fish and for environmental monitoring, since it permits the quantification of multielements simultaneously. ACKNOWLEDGEMENTS This study had financial support of Fund of Support to Research of Universidade Metodista de Piracicaba and technical support from Laboratório Nacional de Luz Síncrotron LNLS under research proposal D9B - XRF REFERENCES 1. Tavares, T. M.; Carvalho, F. M., Avaliação da Exposição de Populações Humanas A Metais Pesados No Ambiente: Exemplos do Recôncavo Baiano, Química Nova, 15, pp (199).. Iyengar, G. V.; Sansoni, B. International Atomic Energy Agency, (198). 3. Simabuco, S. M.; Matsumoto, E., Total reflection with synchrotron radiation (SR-XRF) for rainwater analysis, Spectrochimica Acta, Part B: Atomic Spectroscopy, 55, pp (). 4. Sellanes, A. G.; Santos, N. N.; São Clemente, S. C.; Mársico, E. T.; Oliveira, G. A. In: XVII Congresso Brasileiro de Ciência e Tecnologia de Alimentos, Fortaleza, (). 5. Mantovani, D. M.; Morgano, M. A.; Damasceno, C. F. In: XVII Congresso Brasileiro de Ciência e Tecnologia de Alimentos, (). 6. Franco, G., Tabela de Composição Química dos Alimentos, Atheneu, São Paulo&Brasil (1998). INAC 5, Santos, SP, Brazil.