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Study on the Bio-accumulation, Elimination and Distribution of Nitrobenzene in Carassius Auratus and Cyprinus Carpio

Author: ZhangXiaoYue
Tutor: ZhaoXiaoSong
School: Jilin Agricultural University
Course: Environmental Engineering
Keywords: Nitrobenzene Carp Carp Enrichment Release
CLC: X174
Type: Master's thesis
Year: 2008
Downloads: 126
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Abstract

The nitrobenzene (Nitrobenzene) is a highly toxic chemicals, is one of our identified 58 priority toxic chemicals control, environmental priority control toxic organic pollutants in the world \It is widely used in the production of pesticides, fuels, explosives, pharmaceuticals, polymers and other chemical products. Nitrobenzene industrial wastewater from the the nitrobenzene production process and the production of aniline in the environment, polluting rivers. Aquatic life toxicity test methods to study the enrichment of nitrobenzene to aquatic organisms, is an essential part of the evaluation nitrobenzene compounds risk, and to provide a basis for further study of the toxicity of these compounds. In this study, a semi-static water contact exposure of carp and carp exposed to 0.5mg / L and 3.0mg / L nitrobenzene, bio-accumulation and release test, Gas Chromatography of nitrobenzene content in fish body . Sample pre-processing technique using homogenate combined extraction and ultrasonic extraction method, the extraction rate is fast, the extraction efficiency is high and stable, high sample recovery. Purification of the sample using a homemade column method of purification, wherein filled with alumina and anhydrous sodium sulfate. The results show that: the high, the performance of the low-dose group of fish in different organs of the enrichment of nitrobenzene is basically the same. Which, gills, intestinal uptake of nitrobenzene is more rapid accumulation of large carp gill nitrobenzene maximum concentration value of 15.21mg/kg maximum concentration value 13.41mg/kg carp gills. Nitrobenzene allocated a number of muscle. Liver, kidney enrichment curve presents a different variation, indirect proof of the metabolic conversion of nitrobenzene. Heart gradually stabilized around 2.5 days after reaching the maximum enrichment. Enrichment factor of 0.5mg / L group, low-dose group processing fish. 3.0mg / L nitrobenzene processing, the carp gills nitrobenzene enrichment coefficient of 2.35, intestinal 2.30, muscle 1.60, liver 1.61, kidney 1.95, heart 1.34; 0.05mg / L nitrobenzene concentration group : 5.00 gills, intestinal 4.32, muscle 3.04, liver 3.42, kidney 3.8, heart 2.6. Compared between the different concentration groups, enrichment and release of fish nitrobenzene showed the same regularity, different concentrations of the same biological differences bioconcentration factor, low concentrations of biological rich relatively stable set of factors than the high concentration group Bioconcentration Factor enrichment Bioconcentration peak time is also different, exposure to high concentrations of biological first reach enrichment peak at low concentration. Enrichment factor of different genotypes of the various organs of the fish by the same dose group were compared, carp nitrobenzene easier enrichment, accumulated a large quantity. Fish reared in 0.05 concentration of nitrobenzene aqueous solution of 4.5 days the Shimizu release test results show that the fish release early organ nitrobenzene cleared quickly, the release rate in line with a kinetic equation, c = αe ^{- k · t , the release of the various organs of the fish half-life of 13.0-19.0 h, the underlying index between 0.795-1.832. The gills within nitrobenzene concentration 95%, cardiac release of up to 95% in 82h 56h release. But clear not completely. Enrichment factor of nitrobenzene in the various tissues and organs of the two in fish have some differences in the enrichment of nitrobenzene, the gills enrichment, the gills of the carp high dose group and low dose group The cumulative amount of nitrobenzene were 0.050mg and 0.018mg, carp were 0.033mg and 0.016 mg. The heart in nitrobenzene accumulated less high, the low-dose group were 0.003mg, 0.001mg. Calculate the average cumulative amount of different species of fish of various organs in the body nitrobenzene cumulative amount of the distribution law, showing muscles gt; gill gt; intestinal gt; kidney gt; liver gt; law of the heart. The results of this study is the evaluation of nitrobenzene is an important indicator of the environmental impact aquatic ecosystems and harm, for the the nitrobenzene pollution hazards to fish further study its safety impact of fisheries to provide basic information.}

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