• Title/Summary/Keyword: Toxicity Units(TU)

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Acute Toxicity Test for Wastewater from Several Drainage Canals and Discharges Using Daphnia Magna (생태독성도를 이용한 공단배수 및 공장배출수의 독성도 조사)

  • Park, Dong-Gyu;Bae, Hun-Kyun
    • Journal of Environmental Science International
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    • v.20 no.7
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    • pp.811-818
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    • 2011
  • Daphnia Magna Stratus has been widely accepted as useful species for estimating the toxicity of chemicals to aquatic invertebrate and recommended as species for the testing chemicals from the international guideline as well as Korean guideline. The study was performed for the acute toxicity test by using water flea(D. Magna) for effluents from several wastewater treatment plants and drainage canals in GyeongBuk area. Five heavy metals, 1,4-Dioxane and Perchlorate were tested. Most Toxicity Units(TU) of Industrial wastewater effluents were less than 1 which means effluent was not toxic to D. Magna. However, effluents containing 1,4-Dioxane and Perchlorate were significantly toxic to D. Magna. Therefore, facilities should reduce the 1,4-dioxane since new regulations will force them after the year of 2011.

Application of Toxicity Identification Evaluation Procedures for Toxic Effluents from the Aluminum Rolling Industry (알루미늄 가공 공장 배출 방류수의 독성 원인물질 탐색)

  • Ra, Jin-Sung;Lee, Jiho;Kim, Ki-Tae
    • Journal of Environmental Health Sciences
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    • v.41 no.5
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    • pp.305-313
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    • 2015
  • Objectives: The objective of this study is to identify toxicants causing acute toxicity in effluents from the aluminum rolling industry that violate the discharge limits in Korea. Methods: Whole effluent toxicity tests (WET) were conducted on effluent discharged from the aluminum rolling industry following the US EPA WET test methods. We collected effluent samples three times and evaluated acute toxicity by using Daphnia magna. We employed toxicity identification evaluation (TIE) procedures to identify toxicants causing toxicity in the effluent. Results: No specific chemical groups were identified in the seven different manipulations applied to the of wastewater effluent samples showing 1.3 toxic units (TU) according to the TIE phase I procedures. Water quality parameters for water hardness, electric conductivity and heavy metals (Mn) were 4,322 mg/l as $CaCO_3$, 11.39 mS/cm, and $5,551{\mu}g/l$, respectively. Considering water hardness and reference toxicity, high concentrations of Mn can be disqualified from the causative toxicants. Consequently, high ionic concentrations of $Na^+$(1,648 mg/l), $Ca^{2+}$(1,048 mg/l), $Mg^{2+}$(1,428 mg/l) and $SO_4{^{2-}}$(7,472 mg/l) were identified to be causative toxicants. Water hardness and electric conductivity exceed the $EC_{50}$ value obtained by biological toxicity tests using Daphnia magna. Conclusion: According to TIE procedures, high salt concentration is determined to be a major toxicant in the effluent of agro-industrial wastewater treatment plants receiving wastewater from the aluminum rolling industry.