The results of scientific and applied investigations on mercury contamination in the areas impacted by gold mining in Siberia and the Far East were considered. Gold mining has an impact on the contamination not onl...The results of scientific and applied investigations on mercury contamination in the areas impacted by gold mining in Siberia and the Far East were considered. Gold mining has an impact on the contamination not only in industrial but in residential territories too. The mutual Russian Chinese investigation on mercury contamination of the Amur (Heilongjiang) River was proposed. The program of solving of the problems of mercury contamination in Russian gold mining areas is discussed.展开更多
Six hundred and thirty-four food samples of six kinds were collected from Beijing,Shanghai, Jiangsu, Sichuan, Jilin and Guangdong areas, China and Hg, Pb, Cd contents were determined. The results showed that their lev...Six hundred and thirty-four food samples of six kinds were collected from Beijing,Shanghai, Jiangsu, Sichuan, Jilin and Guangdong areas, China and Hg, Pb, Cd contents were determined. The results showed that their levels in the Chinese foods were low; their levels in meat, egg, milk and fish were generally below the national hygienic standard. The average daily dietary intake of Hg, Pb, Cd were 7.25 μg, 103.77μg and 30.72 μg respectively and they were all less than the ADI established by WHO展开更多
Creation of hydroelectric reservoirs in a certain large water system of China has led to a marked rise in mercury content of fish. Correlation analysis and stepwise regression of R (ratio of mercury content in carp fr...Creation of hydroelectric reservoirs in a certain large water system of China has led to a marked rise in mercury content of fish. Correlation analysis and stepwise regression of R (ratio of mercury content in carp from 12 reservoirs and that from rivers of the same water system) and various hydrologic parameters demonstrated that the ratio of catchment area and runoff was the crucial limiting factor. Other limiting factors were the ratio of flooding area of land and reservoir area of dead storage capacity, and the reciprocal of reservoir area. On this basis, the prediction equations of mercury accumulation in carp after reservoir construction, with one and two parameter respectively, were obtained. All these prediction models were proved to be of high precision.展开更多
The Kaw Nation has been collecting water, sediment, and fish samples from Kaw Lake and upper Arkansas River from 2007 to present to examine the concentrations of Mercury and other heavy metals to protect the health of...The Kaw Nation has been collecting water, sediment, and fish samples from Kaw Lake and upper Arkansas River from 2007 to present to examine the concentrations of Mercury and other heavy metals to protect the health of the tribal members. Kaw Lake is in the North-Central part of Oklahoma. Kaw Lake is a permanent water body constructed in 1976 by the Army of Corps of Engineers. The Lake is consistently fed by the Arkansas River and other tributaries as runoff coming all the way from Colorado through Kansas to Kaw Lake of Oklahoma. The Lake has a surface area of 26.64 square miles (69 km<sup>2</sup>) and shoreline of 168 miles (270 km) with a total drainage area of 56,345 square miles (145,393 km<sup>2</sup>) and an average water depth of 8 meters. The water and fish samples were collected from 7 sites of Kaw Lake, once in a month and the fish samples once in a year during summertime, early July to end of July. The fish samples focused on 5 sport, predator, and bottom dwelling species of large consumable size, greater than 200 mm length and 560 grams weight. The five fish sampled were Catfish, White bass, Largemouth and Smallmouth bass, Black and White crappie. The fish and water samples were sent to Accurate Environmental Labs for detailed analysis. Predator species were analyzed as fillet and the bottom dwellings as a whole fish using EPA Method 7471A-M. Mercury from Water and Fish Tissue Samples were analyzed by Atomic Fluorescence Spectrometry. The laboratory analysis indicated that all the Mercury concentration in the fish samples except in Blue Catfish and Spotted Bass fall below the Maximum Contaminant Level (MCL) of 0.5 mg/kg.展开更多
China is one of countries with the highest mercury production in the world. The Guizhou Province in Southwestern China is currently one of the world's most important mercury production areas. In order to study the...China is one of countries with the highest mercury production in the world. The Guizhou Province in Southwestern China is currently one of the world's most important mercury production areas. In order to study the neurotoxicity of rice from Qingzhen Chemical Plant area and probe into the signal transduction molecular mechanism of injury in rat brain stimulation by mercury contaminated rice. The rats were exposed to mercury contaminated rice for 20 d. Both of the measurements of NO and NOS were processed according to the protocol of the kit. The effect of Hg contaminated rice on the expression of c-fos mRNA in rat brain and the expression of c-FOS protein in cortex, hippocampus were observed using reverse transcription polymerase chain reaction(RT-PCR) and immunocytochemical methods. The results showed the neural transmitter NO and NOS in brain were significantly change between exposure groups and control group; the mercury polluted rice induced significantly the expression of c-fos mRNA; the c-FOS positive cells in hippocampus and cortex of exposure groups were significant different from control group(p<0.01). It could be concluded that nitric oxide was involved in mercury contaminated rice induced immediate early gene c-fos expressions in the rat brain. Through food chain, local ecosystem and health of local people iave been deteriorated seriously by mercury. This serious situation will last a long period. In order to alleviate mercury pollution, more work needs to do.展开更多
The use of filamentous fungi in bioremediation of heavy metal contamination has been developed recently. This research aims to observe the capability of filamentous fungi isolated from forest soil for bioremediation o...The use of filamentous fungi in bioremediation of heavy metal contamination has been developed recently. This research aims to observe the capability of filamentous fungi isolated from forest soil for bioremediation of mercury contamination in a substrate. Six fungal strains were selected based on their capability to grow in 25 mg/L Hg2＋-contaminated potato dextrose agar plates. Fungal strain KRP1 showed the highest ratio of growth diameter, 0.831, thus was chosen for further observation. Identification based on colony and cell morphology carried out by 18S rRNA analysis gave a 98% match to Aspergillusflavus strain KRP1. The fungal characteristics in mercury（II） contamination such as range of optimum pH, optimum temperature and tolerance level were 5.5-7 and 25-35℃ and 100 mg/L respectively. The concentration of mercury in the media affected fungal growth during lag phases. The capability of the fungal strain to remove the mercury（II） contaminant was evaluated in 100 mL sterile 10 mg/L Hg2＋-contaminated potato dextrose broth media in 250 mL Erlenmeyer flasks inoculated with 108 spore/mL fungal spore suspension and incubation at 30℃ for 7 days. The mercury（II） utilization was observed for flasks shaken in a 130 r/min orbital shaker （shaken） and non- shaken flasks （static） treatments. Flasks containing contaminated media with no fungal spores were also provided as control. All treatments were done in triplicate. The strain was able to remove 97.50% and 98.73% mercury from shaken and static systems respectively. A.flavus strain KRPI seems to have potential use in bioremediation of aqueous substrates containing mercury（II） through a biosorption mechanism.展开更多
Electric fishes(Gymnotiformes)inhabit Central and South America and form a relatively large group with more than 200 species.Besides a taxonomic challenge due to their still unresolved systematic,wide distribution and...Electric fishes(Gymnotiformes)inhabit Central and South America and form a relatively large group with more than 200 species.Besides a taxonomic challenge due to their still unresolved systematic,wide distribution and the variety of habitats they occupy,these fishes have been intensively studied due to their peculiar use of bioelectricity for electrolocation and communication.Conventional analysis of cells,tissues and organs have been complemented with the studies on the electric organ discharges of these fishes.This review compiles the results of 13 bioassays developed during the last 50 years,which used the quickness,low costs and functionality of the bioelectric data collection of Gymnotiformes to evaluate the effects of environmental contaminants and neuroactive drugs.展开更多
文摘The results of scientific and applied investigations on mercury contamination in the areas impacted by gold mining in Siberia and the Far East were considered. Gold mining has an impact on the contamination not only in industrial but in residential territories too. The mutual Russian Chinese investigation on mercury contamination of the Amur (Heilongjiang) River was proposed. The program of solving of the problems of mercury contamination in Russian gold mining areas is discussed.
文摘Six hundred and thirty-four food samples of six kinds were collected from Beijing,Shanghai, Jiangsu, Sichuan, Jilin and Guangdong areas, China and Hg, Pb, Cd contents were determined. The results showed that their levels in the Chinese foods were low; their levels in meat, egg, milk and fish were generally below the national hygienic standard. The average daily dietary intake of Hg, Pb, Cd were 7.25 μg, 103.77μg and 30.72 μg respectively and they were all less than the ADI established by WHO
文摘Creation of hydroelectric reservoirs in a certain large water system of China has led to a marked rise in mercury content of fish. Correlation analysis and stepwise regression of R (ratio of mercury content in carp from 12 reservoirs and that from rivers of the same water system) and various hydrologic parameters demonstrated that the ratio of catchment area and runoff was the crucial limiting factor. Other limiting factors were the ratio of flooding area of land and reservoir area of dead storage capacity, and the reciprocal of reservoir area. On this basis, the prediction equations of mercury accumulation in carp after reservoir construction, with one and two parameter respectively, were obtained. All these prediction models were proved to be of high precision.
文摘The Kaw Nation has been collecting water, sediment, and fish samples from Kaw Lake and upper Arkansas River from 2007 to present to examine the concentrations of Mercury and other heavy metals to protect the health of the tribal members. Kaw Lake is in the North-Central part of Oklahoma. Kaw Lake is a permanent water body constructed in 1976 by the Army of Corps of Engineers. The Lake is consistently fed by the Arkansas River and other tributaries as runoff coming all the way from Colorado through Kansas to Kaw Lake of Oklahoma. The Lake has a surface area of 26.64 square miles (69 km<sup>2</sup>) and shoreline of 168 miles (270 km) with a total drainage area of 56,345 square miles (145,393 km<sup>2</sup>) and an average water depth of 8 meters. The water and fish samples were collected from 7 sites of Kaw Lake, once in a month and the fish samples once in a year during summertime, early July to end of July. The fish samples focused on 5 sport, predator, and bottom dwelling species of large consumable size, greater than 200 mm length and 560 grams weight. The five fish sampled were Catfish, White bass, Largemouth and Smallmouth bass, Black and White crappie. The fish and water samples were sent to Accurate Environmental Labs for detailed analysis. Predator species were analyzed as fillet and the bottom dwellings as a whole fish using EPA Method 7471A-M. Mercury from Water and Fish Tissue Samples were analyzed by Atomic Fluorescence Spectrometry. The laboratory analysis indicated that all the Mercury concentration in the fish samples except in Blue Catfish and Spotted Bass fall below the Maximum Contaminant Level (MCL) of 0.5 mg/kg.
文摘China is one of countries with the highest mercury production in the world. The Guizhou Province in Southwestern China is currently one of the world's most important mercury production areas. In order to study the neurotoxicity of rice from Qingzhen Chemical Plant area and probe into the signal transduction molecular mechanism of injury in rat brain stimulation by mercury contaminated rice. The rats were exposed to mercury contaminated rice for 20 d. Both of the measurements of NO and NOS were processed according to the protocol of the kit. The effect of Hg contaminated rice on the expression of c-fos mRNA in rat brain and the expression of c-FOS protein in cortex, hippocampus were observed using reverse transcription polymerase chain reaction(RT-PCR) and immunocytochemical methods. The results showed the neural transmitter NO and NOS in brain were significantly change between exposure groups and control group; the mercury polluted rice induced significantly the expression of c-fos mRNA; the c-FOS positive cells in hippocampus and cortex of exposure groups were significant different from control group(p<0.01). It could be concluded that nitric oxide was involved in mercury contaminated rice induced immediate early gene c-fos expressions in the rat brain. Through food chain, local ecosystem and health of local people iave been deteriorated seriously by mercury. This serious situation will last a long period. In order to alleviate mercury pollution, more work needs to do.
基金High gratitude to Directorate General of Higher Education, Ministry of Education and Culture, Republic of Indonesia for the full support through DIKTI Scholarship, Brawijaya University, and Yamaguchi University
文摘The use of filamentous fungi in bioremediation of heavy metal contamination has been developed recently. This research aims to observe the capability of filamentous fungi isolated from forest soil for bioremediation of mercury contamination in a substrate. Six fungal strains were selected based on their capability to grow in 25 mg/L Hg2＋-contaminated potato dextrose agar plates. Fungal strain KRP1 showed the highest ratio of growth diameter, 0.831, thus was chosen for further observation. Identification based on colony and cell morphology carried out by 18S rRNA analysis gave a 98% match to Aspergillusflavus strain KRP1. The fungal characteristics in mercury（II） contamination such as range of optimum pH, optimum temperature and tolerance level were 5.5-7 and 25-35℃ and 100 mg/L respectively. The concentration of mercury in the media affected fungal growth during lag phases. The capability of the fungal strain to remove the mercury（II） contaminant was evaluated in 100 mL sterile 10 mg/L Hg2＋-contaminated potato dextrose broth media in 250 mL Erlenmeyer flasks inoculated with 108 spore/mL fungal spore suspension and incubation at 30℃ for 7 days. The mercury（II） utilization was observed for flasks shaken in a 130 r/min orbital shaker （shaken） and non- shaken flasks （static） treatments. Flasks containing contaminated media with no fungal spores were also provided as control. All treatments were done in triplicate. The strain was able to remove 97.50% and 98.73% mercury from shaken and static systems respectively. A.flavus strain KRPI seems to have potential use in bioremediation of aqueous substrates containing mercury（II） through a biosorption mechanism.
基金Supported by the Coordination of Improvement of Higher Education Personnel(CAPES),Ministry of Science,Technology and Innovation of Brazil(Grant No.PROAP/2014).
文摘Electric fishes(Gymnotiformes)inhabit Central and South America and form a relatively large group with more than 200 species.Besides a taxonomic challenge due to their still unresolved systematic,wide distribution and the variety of habitats they occupy,these fishes have been intensively studied due to their peculiar use of bioelectricity for electrolocation and communication.Conventional analysis of cells,tissues and organs have been complemented with the studies on the electric organ discharges of these fishes.This review compiles the results of 13 bioassays developed during the last 50 years,which used the quickness,low costs and functionality of the bioelectric data collection of Gymnotiformes to evaluate the effects of environmental contaminants and neuroactive drugs.
