碩士 / 國立高雄師範大學 / 生物科技系 / 105 / With the development of technology and requirement of regulations, industrial wastewater was collected and treated by wastewater treatment systems before being discharged into the aquatic environment. Although the water quality of treated effluents fulfills effluent standards, but the trace concentrations of some chemicals (e.g. heavy metals, polar or nonpolar organic compounds) in effluents may have toxic effects on aquatic organisms. Therefore, the aim of this study was to identify the major chemicals causing the toxicity of industrial effluents to standard test organisms using several approaches of Toxicity Identification Evaluation (TIE) recommended by United States Environmental Protection Agency.
Effluents from four industries (A, B, C, D) were collected to performed biological toxicity tests in order to find effluents with high toxicity for TIE tests. The results showed that effluents from the industries A, C, D mostly fulfilled effluent standards, but those from industry B caused high toxicity effects to test organisms. Five TIE test were conducted for effluents from the industry B. The effluents from the industry B were subjected to six treatments: aeration, ethylenediamine tetraacetic acid (EDTA) additions, Na2S2O3 additions, C18 solid phase extraction, anion and cation exchange resin, respectively. The results of the first TIE test showed that the TUa (Acute toxicity unit) values were decreased for effluents after being treated with cation exchange resin, EDTA additions and C18 solid phase extraction in comparison with untreated effluents. It indicated that effluent toxicity might result from cationic metals, nonpolar organics and metal complexes. On the contrary, the TUa values increased for effluents after being treated with aeration, Na2S2O3 additions and anion exchange resin. It suggested that volatile compounds, ammonium and anion ions in effluents might not cause toxic effects to water fleas. The results of the 2nd to 4th TIE test showed that the major factors causing toxicity of effluents were copper and aluminum, but not nonpolar organic compounds and metal complexes. The 5th TIE test demonstrated these results. The results of the biological toxicity test for single compound were compared with those for effluents. It showed that median lethal concentrations of copper and aluminum in the single system were lower than concentration of these chemicals in some treated and untreated effluents which caused toxic effects to water fleas. The results confirmed that the major factors causing acute toxicity of effluents were copper and aluminum. Thus, it is suggested that the use of raw materials contained copper and aluminum should be decreased, or removal efficiency of these two chemicals from wastewater should be improved in order to reduce toxic effects of these chemicals to aquatic ecosystems.
| Identifer | oai:union.ndltd.org:TW/105NKNU0111010 |
| Date | January 2017 |
| Creators | Ji-Mu Lyu, 呂季穆 |
| Contributors | Chien-Jung Tien, 田倩蓉 |
| Source Sets | National Digital Library of Theses and Dissertations in Taiwan |
| Language | zh-TW |
| Detected Language | English |
| Type | 學位論文 ; thesis |
| Format | 114 |
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