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Monitoring of fluoride content in the environment around an aluminium smelter plant
Poster Session 4F. Environmental comparison of tests soil and soil invertebrates were selected on lands without irrigation. In studied agricultural lands following taxonomic groups of invertebrates are found: Lumbricidae,Julidae, Coleoptera, Dermoptera. The analysis performed beforehand by atomic absorption analysis of soil and animal tissues has shown that in arable strata of irrigated lands is kept in 1.5--5 times greater level of technogenic elements - Ni, Cd, Ph, than on fields without irrigation. Different taxonomic groups of soil invertebrates response to anthropogenic contamination and accumulateheavy metals in the organism differently. The greater concentration function possess Julidae which accumulateshundreds times more toxicants than their contents in soil. Even though concentration Ph in soil is on the allowable level, in animal tissue it reaches 511.2 mglkg in the recalculation on the dry mass. Except these animals but in smaller degree Ni, Cd and Ph are accumulated by maggots of Elateridae, Thenebrionidae,Curculionidae. Herewith, often it is observed accumulation of metals in animal body at a greaterdegrees on lands withoutirrigation,than on irrigated fields.
IP4F1141
A STUDY OF AN EGYPTIAN MUMMY "ISETIRI HETES" FROM THE PTOLEMAIC PERIOD 1\1-1 B.C.
M. Klys -, J. Bialka, T. Lech, 1. Zi~ba·Palus, B. Opolska-Bogusz, B. Pr6chnicka. Collegium Medicum Jagiellonian University. Institute ofForensic Medicine, Poland Chemical, physicochemical, serological and histological examinations of the fragments of an Egyptian mummy dated between the fourth and first century B.C. were performed. An analysis of the infrared spectra of the fragments indicated a type of resin originating from the Copal group. Physicochemical investigations showed that main chemicalelements such as Ca, Mg, Na, K, P and trace chemical elements such as Fe, Zn, Cu and Pb occurred in bone fragments in proportionstypical for people living today. In tooth fragments,values werc sinilar to normal except for K, P and Zn, which were lower, and Pb, which was absent. In the fingernails, most elements were found in much higher concentrations except for Cu and Pb, which were lower. Human protein was identified, the ABO phenotype was determined as type B, and morphological disruption of the cells was observed. The results of the study in terms of their implicationson mummification are discussed.
IP4F115I CHANGES IN CHOSEN BIOCHEMICAL PARAMETERS IN URINEOF THE CHILDREN LIVING IN THE COPPERBASINAS AN EFFECTOF ENVIRONMENTAL EXPOSURE IN THE LONGITUDINAL STUDIES
Ewa Bakonska-Pacori *1, Irena Nowacka,Krzysztof A. Sobiech, Antoni Janusz", /Physiology Dept., 2Anthropology Dept., Acad. of Phys. Educ., Wrocfaw, Poland The wide environmental degradation consequences on the LubinGlog6w Copper Basin area evoked by the copper minesand foundries activity is shown especially by the constant exposure to the heavy metals presence as Ph, Cd, Cu, Zn, Fe, As. These metals by the accumulation effect give the extremal kind of toxicity, especially in the children organisms. The research work was led from 1991 to 1997 in the urine obtained from the same group of children living in the Copper Basin. In urine were determinated protein and creatinine concentrations and the level of Pb, Cd, Cu, Zn, Fe, Ca, Mg. The data obtained in particular years display the increase in the Pb and Cd concentration in the urine above the upper border of allowed values. It was observed a 1.5 fold increase in the Pb concentration and in the last year (1996--97) - systematical decrease of this parameter as
231
an effect of widely constituted both environmental and health protection. During the first years the copper concentration was higher than the physiologicallyaccepted values but on last years it started to decrease from 0.18 to 0.10 tLmollrnrnol of creatinine. It was noticed a decrease of Ca and Mg excretion, what could be a result of the heavy metals competitionwith these bioelernents in the organisms. The toxic metals exposure is correlated with a decreased psychomotoric efficiency and morphologic development of the investigated children.
IP4F116I
ELEMENTAL STATUS OF CATTlE GRAZING ADJACENT TO A PORTION OF NATIONAL HIGHWAY
N. Sahoo ., B. Patra, S.K. Ray,P.K. Das. DepartmentofMedicine, Veterinary College, Orissa University of Agriculture and Technology, Bhubaneswar; India A study was carried out to assess the extent of automobile pollution with respect to cadmium (Cd), copper (Cu), manganese (Mn), lead (Ph) and zinc (Zn) near a portion of NationalHighway No.5 running between Bhubaneswarand Cuttaek, one of the busiest motorways in India (Vehicularload is about 30,000pay day). Blood, soil and fodder samplescollected at varioussites were analysed in atomic absorption spectrophotometer using the standard procedures of analysis. The mean Cd, Cu, Pb and Zn concentration in blood samples of cattle grazing freely near this highway were estimated to be 0.008. 0.993, 0.271 and 1.335 ppm as against 0.008, 0.816, 0.130 and 1.090 ppm in animals near a village road (control), respectively. Manganese could not be detected in any of the blood samples. Average values of composite fodder samples i.e. Penicum repensand Cynodendactylon for Cd, Cu, Mn, Pb and Zn were found out to be 0.008, 0.335, 2.900, 0.503 and 0.980 ppm near highway and 0.006, 0.242, 1.725,0.261 and 0.643 ppm in control area, respectively, Average concentration of the heavy metals i.e., Cd, Cu, Mn, Pb and Zn in the surface soil near highway were 0.015, 0.380, 4.983, 0.560 and 1.749 ppm whereas 0.014, 0.230, 3.131, 0.340 and 1.060 ppm in control area, respectively. Statistical analysis revealed that the cattle population inhabitating near this portion of highway are under the grip of the subtle effects of heavy metals especially lead which is most likely through the contaminated fodder and/or soil. Necessary steps have been taken in order to get rid of the automobile pollution.
IP4F1171
MONITORING OF FLUORIDE CONTENT IN THE ENVIRONMENT AROUND AN ALUMINIUM SMELTER PLANT
N. Sahoo *, S.K. Ray. DepartmentofMedicine, Veterinary College. Orissa Universityof Agricultureand Technology, Bhubaneswar; India Thirty villages situated within 10 kms radius from an aluminium smelter plant (National Aluminium Company Ltd.), the largest aluminium producer and exporter of India, were selected using cross-sectional epidemiological methods in order to assess the degree of fluoride pollution in the vicinity during 1993-1997. Out of the 7629 ruminants (922 sheep, 912 goats and 5795 cattle) examined, 6.0 to 65.4 per cent animals in the selected sample villages showed pathognomonic dental and/or skeletal lesions suggestiveof fluorosis. Minimum and maximum mean fluoride concentration in serum, urine, milk and bone samples were recorded to be 0.12--0.86 ppm, 2.05-30.23 ppm, 0.21-0.68 ppm and 4125-18636 mglkg, respectively. Average fluoride content in the water (pond, river and well), soil (surface and deep) andfodder (Oryza sativa and Cynodon dactyIon) ranged between 0.13-3.84 ppm, 0.34-1.96 ppm and 2.91-100.6 ppm, respectively. Mean fluoridecontent of different organs of fresh water fish tCirrihinus mrigala; Catla calla and Labeo rohita) varied from 9.36-201.24 mglkg. Although the concentration of fluoride in
232
Poster Session 4F. Environmental
majority of the biological samples were analysed to be statisticaJIy higher than the corresponding samples of control area, no definite pattern of fluoride pollution, which is very .likely in an industrial fluorosis, were observed around this smelter in relation to the season of the year, direction of the prevailing wind and distance from the smelter. Isopleths of various biological samples revealed the coexistence of endemic fluorosis in this locality. Suitable recommendations have been made to aJIeviate the possible hazards associated with endemic and/or industrial fluorosis.
in urine was 0.66 ± 0.44 (range 0.12-4.65) ppm, a 0.07 ± 0.08 ppm increase over baseline values obtained before (P < 0.01). When expressed as a function of creatinine concentration and of specific gravity, fluoride levels were, respectively, as follows: 1.47 ± 1.04 mg/g and 0.66 ± 0.44 mglIJ24 h. Values obtained are within normal limits as referred to in the literature for adults. These results are important from public health point of view, particularly for control of pathologies such as hypocalcemia, hypomagnesemia among others, and for management of fluid and electrolyte therapy.
IP4F118!
IP4F120 I
METAL CONCENTRATION IN BIVALVE MOLLUSCS FROM THE COASTOF BUENOS AIRESPROVINCE, ARGENTINA
OPTIMAL MINERALIZATION CONDITIONS FOR TOTAL MERCURY ANALYSES IN HUMAN, ANIMAL, FUNGUS AND ENVIRONMENTAL SAMPLES
N.R. Verrengia Guerrero *, Eva A. Wider. Biomarkers Laboratory, Dept. ofBiological Chemistry, School ofSciences, Buenos Aires University, 4 piso, Pab.II, Buenos Aires (1428), Argentina
S. Jahanbakht *, F. Livardjani, A. Jaeger, A. Lugnier. Centre Anti-Poison, Faculte de Medecine/Ioboratoire de Toxicologie, Faculte de Pharmacie, Strasbourg, France
Analysis of metal concentrations in marine organisms may be considered as a useful tool to assess the extend of pollution of aquatic systems. Bivalve molluscs, such as mussels or clams, have been extensively recommended and employed in several monitoring programs. However, there are few works about metal contaminants in bivalve molluscs from the coastal zones of the Argentine Sea. Therefore, the purpose of this work was to determine the levels of trace metal concentrations (Cd, Cu, Cr, Ni, Pb, and Zn) in the whole body soft tissue of marine clams. The organisms were collected from three sampling stations, along San Clemente Beach, Province of Buenos Aires, Argentina, during April 1996. Sampling station A is relatively unpolluted, in station B urban and industrial effluents are discharged, and in C is located the San Clemente Port. The analysis were performed by atomic absorption spectrophotometry, after the digestion of the samples with concentrated nitric acid. For all the elements analysed, lowest levels were found in bivalves from sampling station A, with means ofO.l4p.g Cd/g, 0.25 iLg Cr/g, 5.14 iLg Culg, 2.09 iLg Nifg, 0.86 iLg Pb/g, and 25.24 iLg Zolg. In general, similar values were observed for Cd, Cr, and Ni in organisms collected at sampling station B. However, in this zone the highest levels for Cu, Pb, and Zn were obtained (mean values of 11.80, 1.66, and 31.75 iLglg, respectively). The levels of Cu and Zn in molluscs collected at sampling station C were similar to those from station A. Instead for Cd, Cr, and Ni the highest levels were observed (1.07, 0.57, and 3.66 iLglg, respectively). For Pb, the values were similar to those observed in molluscs from station B. These data may be useful not only to assess the levels of metals in bivalve molluscs of this zone, but also to compare with future monitoring programs.
Literature results of mercury assays in biological and environmental samples show important interlaboratory variations. These discrepancies are not due to the analytical methods used, which are generally of high accuracy and precision (spectrometric atomic absorption, inductively coupled plasma-mass spectrometry), but to the lack of complete mineralization of the organic material. That's why we have established the best conditions of samples mineralization by studying a wide range of experiments. These were carried out on human blood, plasma and urine, animal muscles (fishes), mushrooms, water and sediments by varying physical and chemical parameters (acid and basic treatments, temperature, time, mineralization volume, organic matrix composition, mercury concentrations). Optimal conditions for a complete recuperation of mercury in blood and plasma were obtained using a mixture of nitric and sulphuric acid (3 mL HN03, 2 mL H2S04) at 80°C for 15 min, with a 200 ilL sample, in a total volume of 30 mL. For urine and environmental water samples, the best results were obtained in the same conditions, but without heating, at room temperature (20°C), and only for 10 min. Fish tissues (500 mg) were treated for an optimal mercury recuperation in a more acid medium (6 mL HN03, 4 mL H2S04), at 60°C for 1 h. For mushrooms (l g), maximal efficiency was obtained, as for the blood mineralization, but at 60°C for I h. Sediments (500 mg), require more drastic conditions (fish acidic medium, 150°C, 24 h). These conditions show a high mercury reproductibility and accuracy and a higher than 90% mercury recuperation.
IP4F1191 AN EVALUATION OF FLUORIDE EXCRETION IN CHILDREN FROMFIVE ELEMENTARY SCHOOLS IN CARACAS,VENEZUELA
Gladys R. Galf *, Carlos Mujica, Anafs Romero, Adelaida Matos, Jesus Rodriguez. College ofPharmacy, Universidad Central de Venezuela, Caracas, Venezuela In 1994, the Venezuelan Ministry of Health initiated a program for fluoridation of salt for human consumption. Fluoride excretion in urine was measured previous to application of the program. In order to evaluate this program, in 1997 we determined fluoride excretion in urine from 292 children with between 3 and 7 yr old, from five elementary schools in Caracas. Samples were taken from the first urine voided in the morning. Fluoride was determined by a direct potentiometric method using an ion selective electrode; creatinine was determined by the alkaline picrate reaction and the specific gravity, using the Urisystem refractometer. Fluoride average concentration
I P4F121 I EXPERIMENTAL ECOTOXICOLOGICAL MODEL FOR THE BEHAVIORAL STUDY IN THE ENVIRONMENT OF INORGANIC ANDORGANIC MERCURY
S. Jahanbakht *, E. Ruhl, F. Livardjani, A. Jaeger, A. Lugnier. Centre Anti-Poison, Faculte de Medecine/Societe Carrare/Laboratoire de Toxicologie, Faculte de Pharmacie, Strasbourg, France The studies were achieved separately with inorganic and organic mercury (respectively, mercury chloride, methylmercury chloride) according to temperature and pH. The method selected was an interactive model formed of two compartments (water and air). It was represented by a 200 L capacity aquarium filled with 100 L of aqueous medium. The complete system was thermostated at different temperatures (24, 28 and 30°C) and adjusted to several pH values (1.0-10.0), in presence of HgCl2 or HgCH3CI (l mgIL). Mercury was determined directly in air and in water for inorganic mercury. and after mineralization for the organic compound, by an original laboratory-prototype apparatus conceived on the principle of cold vapor flameless spectrometric atomic absorption. The determination and mineralization conditions were optimized so as to obtain higher sensitivity and accuracy (90 ng/m! in air, 15 pg in absolute weight). When mercury chloride was used in acid medium (pH < 5), mercury
IP4F1141
A STUDY OF AN EGYPTIAN MUMMY "ISETIRI HETES" FROM THE PTOLEMAIC PERIOD 1\1-1 B.C.
M. Klys -, J. Bialka, T. Lech, 1. Zi~ba·Palus, B. Opolska-Bogusz, B. Pr6chnicka. Collegium Medicum Jagiellonian University. Institute ofForensic Medicine, Poland Chemical, physicochemical, serological and histological examinations of the fragments of an Egyptian mummy dated between the fourth and first century B.C. were performed. An analysis of the infrared spectra of the fragments indicated a type of resin originating from the Copal group. Physicochemical investigations showed that main chemicalelements such as Ca, Mg, Na, K, P and trace chemical elements such as Fe, Zn, Cu and Pb occurred in bone fragments in proportionstypical for people living today. In tooth fragments,values werc sinilar to normal except for K, P and Zn, which were lower, and Pb, which was absent. In the fingernails, most elements were found in much higher concentrations except for Cu and Pb, which were lower. Human protein was identified, the ABO phenotype was determined as type B, and morphological disruption of the cells was observed. The results of the study in terms of their implicationson mummification are discussed.
IP4F115I CHANGES IN CHOSEN BIOCHEMICAL PARAMETERS IN URINEOF THE CHILDREN LIVING IN THE COPPERBASINAS AN EFFECTOF ENVIRONMENTAL EXPOSURE IN THE LONGITUDINAL STUDIES
Ewa Bakonska-Pacori *1, Irena Nowacka,Krzysztof A. Sobiech, Antoni Janusz", /Physiology Dept., 2Anthropology Dept., Acad. of Phys. Educ., Wrocfaw, Poland The wide environmental degradation consequences on the LubinGlog6w Copper Basin area evoked by the copper minesand foundries activity is shown especially by the constant exposure to the heavy metals presence as Ph, Cd, Cu, Zn, Fe, As. These metals by the accumulation effect give the extremal kind of toxicity, especially in the children organisms. The research work was led from 1991 to 1997 in the urine obtained from the same group of children living in the Copper Basin. In urine were determinated protein and creatinine concentrations and the level of Pb, Cd, Cu, Zn, Fe, Ca, Mg. The data obtained in particular years display the increase in the Pb and Cd concentration in the urine above the upper border of allowed values. It was observed a 1.5 fold increase in the Pb concentration and in the last year (1996--97) - systematical decrease of this parameter as
231
an effect of widely constituted both environmental and health protection. During the first years the copper concentration was higher than the physiologicallyaccepted values but on last years it started to decrease from 0.18 to 0.10 tLmollrnrnol of creatinine. It was noticed a decrease of Ca and Mg excretion, what could be a result of the heavy metals competitionwith these bioelernents in the organisms. The toxic metals exposure is correlated with a decreased psychomotoric efficiency and morphologic development of the investigated children.
IP4F116I
ELEMENTAL STATUS OF CATTlE GRAZING ADJACENT TO A PORTION OF NATIONAL HIGHWAY
N. Sahoo ., B. Patra, S.K. Ray,P.K. Das. DepartmentofMedicine, Veterinary College, Orissa University of Agriculture and Technology, Bhubaneswar; India A study was carried out to assess the extent of automobile pollution with respect to cadmium (Cd), copper (Cu), manganese (Mn), lead (Ph) and zinc (Zn) near a portion of NationalHighway No.5 running between Bhubaneswarand Cuttaek, one of the busiest motorways in India (Vehicularload is about 30,000pay day). Blood, soil and fodder samplescollected at varioussites were analysed in atomic absorption spectrophotometer using the standard procedures of analysis. The mean Cd, Cu, Pb and Zn concentration in blood samples of cattle grazing freely near this highway were estimated to be 0.008. 0.993, 0.271 and 1.335 ppm as against 0.008, 0.816, 0.130 and 1.090 ppm in animals near a village road (control), respectively. Manganese could not be detected in any of the blood samples. Average values of composite fodder samples i.e. Penicum repensand Cynodendactylon for Cd, Cu, Mn, Pb and Zn were found out to be 0.008, 0.335, 2.900, 0.503 and 0.980 ppm near highway and 0.006, 0.242, 1.725,0.261 and 0.643 ppm in control area, respectively, Average concentration of the heavy metals i.e., Cd, Cu, Mn, Pb and Zn in the surface soil near highway were 0.015, 0.380, 4.983, 0.560 and 1.749 ppm whereas 0.014, 0.230, 3.131, 0.340 and 1.060 ppm in control area, respectively. Statistical analysis revealed that the cattle population inhabitating near this portion of highway are under the grip of the subtle effects of heavy metals especially lead which is most likely through the contaminated fodder and/or soil. Necessary steps have been taken in order to get rid of the automobile pollution.
IP4F1171
MONITORING OF FLUORIDE CONTENT IN THE ENVIRONMENT AROUND AN ALUMINIUM SMELTER PLANT
N. Sahoo *, S.K. Ray. DepartmentofMedicine, Veterinary College. Orissa Universityof Agricultureand Technology, Bhubaneswar; India Thirty villages situated within 10 kms radius from an aluminium smelter plant (National Aluminium Company Ltd.), the largest aluminium producer and exporter of India, were selected using cross-sectional epidemiological methods in order to assess the degree of fluoride pollution in the vicinity during 1993-1997. Out of the 7629 ruminants (922 sheep, 912 goats and 5795 cattle) examined, 6.0 to 65.4 per cent animals in the selected sample villages showed pathognomonic dental and/or skeletal lesions suggestiveof fluorosis. Minimum and maximum mean fluoride concentration in serum, urine, milk and bone samples were recorded to be 0.12--0.86 ppm, 2.05-30.23 ppm, 0.21-0.68 ppm and 4125-18636 mglkg, respectively. Average fluoride content in the water (pond, river and well), soil (surface and deep) andfodder (Oryza sativa and Cynodon dactyIon) ranged between 0.13-3.84 ppm, 0.34-1.96 ppm and 2.91-100.6 ppm, respectively. Mean fluoridecontent of different organs of fresh water fish tCirrihinus mrigala; Catla calla and Labeo rohita) varied from 9.36-201.24 mglkg. Although the concentration of fluoride in
232
Poster Session 4F. Environmental
majority of the biological samples were analysed to be statisticaJIy higher than the corresponding samples of control area, no definite pattern of fluoride pollution, which is very .likely in an industrial fluorosis, were observed around this smelter in relation to the season of the year, direction of the prevailing wind and distance from the smelter. Isopleths of various biological samples revealed the coexistence of endemic fluorosis in this locality. Suitable recommendations have been made to aJIeviate the possible hazards associated with endemic and/or industrial fluorosis.
in urine was 0.66 ± 0.44 (range 0.12-4.65) ppm, a 0.07 ± 0.08 ppm increase over baseline values obtained before (P < 0.01). When expressed as a function of creatinine concentration and of specific gravity, fluoride levels were, respectively, as follows: 1.47 ± 1.04 mg/g and 0.66 ± 0.44 mglIJ24 h. Values obtained are within normal limits as referred to in the literature for adults. These results are important from public health point of view, particularly for control of pathologies such as hypocalcemia, hypomagnesemia among others, and for management of fluid and electrolyte therapy.
IP4F118!
IP4F120 I
METAL CONCENTRATION IN BIVALVE MOLLUSCS FROM THE COASTOF BUENOS AIRESPROVINCE, ARGENTINA
OPTIMAL MINERALIZATION CONDITIONS FOR TOTAL MERCURY ANALYSES IN HUMAN, ANIMAL, FUNGUS AND ENVIRONMENTAL SAMPLES
N.R. Verrengia Guerrero *, Eva A. Wider. Biomarkers Laboratory, Dept. ofBiological Chemistry, School ofSciences, Buenos Aires University, 4 piso, Pab.II, Buenos Aires (1428), Argentina
S. Jahanbakht *, F. Livardjani, A. Jaeger, A. Lugnier. Centre Anti-Poison, Faculte de Medecine/Ioboratoire de Toxicologie, Faculte de Pharmacie, Strasbourg, France
Analysis of metal concentrations in marine organisms may be considered as a useful tool to assess the extend of pollution of aquatic systems. Bivalve molluscs, such as mussels or clams, have been extensively recommended and employed in several monitoring programs. However, there are few works about metal contaminants in bivalve molluscs from the coastal zones of the Argentine Sea. Therefore, the purpose of this work was to determine the levels of trace metal concentrations (Cd, Cu, Cr, Ni, Pb, and Zn) in the whole body soft tissue of marine clams. The organisms were collected from three sampling stations, along San Clemente Beach, Province of Buenos Aires, Argentina, during April 1996. Sampling station A is relatively unpolluted, in station B urban and industrial effluents are discharged, and in C is located the San Clemente Port. The analysis were performed by atomic absorption spectrophotometry, after the digestion of the samples with concentrated nitric acid. For all the elements analysed, lowest levels were found in bivalves from sampling station A, with means ofO.l4p.g Cd/g, 0.25 iLg Cr/g, 5.14 iLg Culg, 2.09 iLg Nifg, 0.86 iLg Pb/g, and 25.24 iLg Zolg. In general, similar values were observed for Cd, Cr, and Ni in organisms collected at sampling station B. However, in this zone the highest levels for Cu, Pb, and Zn were obtained (mean values of 11.80, 1.66, and 31.75 iLglg, respectively). The levels of Cu and Zn in molluscs collected at sampling station C were similar to those from station A. Instead for Cd, Cr, and Ni the highest levels were observed (1.07, 0.57, and 3.66 iLglg, respectively). For Pb, the values were similar to those observed in molluscs from station B. These data may be useful not only to assess the levels of metals in bivalve molluscs of this zone, but also to compare with future monitoring programs.
Literature results of mercury assays in biological and environmental samples show important interlaboratory variations. These discrepancies are not due to the analytical methods used, which are generally of high accuracy and precision (spectrometric atomic absorption, inductively coupled plasma-mass spectrometry), but to the lack of complete mineralization of the organic material. That's why we have established the best conditions of samples mineralization by studying a wide range of experiments. These were carried out on human blood, plasma and urine, animal muscles (fishes), mushrooms, water and sediments by varying physical and chemical parameters (acid and basic treatments, temperature, time, mineralization volume, organic matrix composition, mercury concentrations). Optimal conditions for a complete recuperation of mercury in blood and plasma were obtained using a mixture of nitric and sulphuric acid (3 mL HN03, 2 mL H2S04) at 80°C for 15 min, with a 200 ilL sample, in a total volume of 30 mL. For urine and environmental water samples, the best results were obtained in the same conditions, but without heating, at room temperature (20°C), and only for 10 min. Fish tissues (500 mg) were treated for an optimal mercury recuperation in a more acid medium (6 mL HN03, 4 mL H2S04), at 60°C for 1 h. For mushrooms (l g), maximal efficiency was obtained, as for the blood mineralization, but at 60°C for I h. Sediments (500 mg), require more drastic conditions (fish acidic medium, 150°C, 24 h). These conditions show a high mercury reproductibility and accuracy and a higher than 90% mercury recuperation.
IP4F1191 AN EVALUATION OF FLUORIDE EXCRETION IN CHILDREN FROMFIVE ELEMENTARY SCHOOLS IN CARACAS,VENEZUELA
Gladys R. Galf *, Carlos Mujica, Anafs Romero, Adelaida Matos, Jesus Rodriguez. College ofPharmacy, Universidad Central de Venezuela, Caracas, Venezuela In 1994, the Venezuelan Ministry of Health initiated a program for fluoridation of salt for human consumption. Fluoride excretion in urine was measured previous to application of the program. In order to evaluate this program, in 1997 we determined fluoride excretion in urine from 292 children with between 3 and 7 yr old, from five elementary schools in Caracas. Samples were taken from the first urine voided in the morning. Fluoride was determined by a direct potentiometric method using an ion selective electrode; creatinine was determined by the alkaline picrate reaction and the specific gravity, using the Urisystem refractometer. Fluoride average concentration
I P4F121 I EXPERIMENTAL ECOTOXICOLOGICAL MODEL FOR THE BEHAVIORAL STUDY IN THE ENVIRONMENT OF INORGANIC ANDORGANIC MERCURY
S. Jahanbakht *, E. Ruhl, F. Livardjani, A. Jaeger, A. Lugnier. Centre Anti-Poison, Faculte de Medecine/Societe Carrare/Laboratoire de Toxicologie, Faculte de Pharmacie, Strasbourg, France The studies were achieved separately with inorganic and organic mercury (respectively, mercury chloride, methylmercury chloride) according to temperature and pH. The method selected was an interactive model formed of two compartments (water and air). It was represented by a 200 L capacity aquarium filled with 100 L of aqueous medium. The complete system was thermostated at different temperatures (24, 28 and 30°C) and adjusted to several pH values (1.0-10.0), in presence of HgCl2 or HgCH3CI (l mgIL). Mercury was determined directly in air and in water for inorganic mercury. and after mineralization for the organic compound, by an original laboratory-prototype apparatus conceived on the principle of cold vapor flameless spectrometric atomic absorption. The determination and mineralization conditions were optimized so as to obtain higher sensitivity and accuracy (90 ng/m! in air, 15 pg in absolute weight). When mercury chloride was used in acid medium (pH < 5), mercury