• Journal of Environmental Science International
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• v.11 no.9
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• pp.851-855
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• 2002

A comparison of Daphnia magna, Ceriodaphnia dubia and Simocephalus mixtus toxicity test was performed to study the relative sensitivities and discrimination abilities with both pore and elutriate water of Woopo wetland sediments. Sediment risk assessment has been done by standardized preparation method of pore and elutriate water described in the joint US EPA-US Army Crops of Engineers manual. Simocephalus mixtus which was obtained from Woopo wetlands in Korea was cultured and applied to sediment toxicity test. Water quality in Woopo wetland had great site and seasonal variations. S. mixtus was more sensitive than D. magna in heavy metal toxicity test. The toxicity results with S. mixtus reflected the water quality of elutriate and pore water. The results also suggested that S. mixtus could be used as a test organism in estimating potential risk of contaminated sediments.

• Environmental Analysis Health and Toxicology
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• v.23 no.4
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• pp.267-276
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• 2008

Acute and chronic toxicities of sediment elutriate and surface water samples collected at Lake Shihwa were evaluated using standard toxicity testing organisms including Vibrio fischeri, Daphnia magna and Moina macrocopa. Acute exposure resulted in toxic effects in all surface water or sediment elutriate samples, except for those collected from the reed swamp and Okgu stream. The rainy season influenced the toxicity of the water samples, presumably either by dilution of point discharge or through introduction of non-point source contaminants through runoff. In the sediment, elutriate and surface water samples, copper was detected above potentially lethal concentration, which may in part explain the observed toxicity. Considering acute toxicities of the surface water streams that direct to the Lake Shihwa, efforts should be warranted to control and reduce discharge of point and non-point sources along Lake Shihwa.

• Journal of Wetlands Research
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• v.2 no.1
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• pp.69-85
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• 2000

Wetlands are generally thought to be among the most fertile and productive ecosystems of the world. They provide a variety of ecological functions to the landscape. In recent years there has been considerable research activity to generate more scientific documentation on the ecological functions of wetlands. Many pollutants released to the environment settle and accumulate in the silt and mud called sediment on the bottoms of wetlands. Contaminated sediment can cause adverse effects to aquatic organism and eventually to ecological system. Sediment toxicity test with water fleas has been done by standardized preparation method of pore and elutriate water methods described in the literature for the need to protect Woopo wetlands. The results of Daphnia magna, Ceridaphnia dubla and Simocephalus sp. toxicity test were compared and discussed in terms of the relative sensitivity and discrimination abilities with both pore and elutriate water obtained from the sediments of Woopo wetlands.

• Korean Journal of Soil Science and Fertilizer
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• v.40 no.4
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• pp.274-279
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• 2007

The toxicitiy of organic sludge such as municipal sewage sludge (MSS), industrial sewage sludge (ISS), alcohol fermentation processing sludge (AFPS) and leather processing sludge (LPS) were evaluated with three environmental biomarkers as acetylcholinesterase, cytochrome P450, and heat shock protein 70 extracted from earthworm (Eisenia fetida). Their toxicities were compared with those of pig manure compost (PMC). MSS, ISS, LPS, and AFPS did not significantly affect the acetylcolinesterase activity, whereas only the elutriate of PMC slightly was increased the activity. MSS, AFPS, and PMC tended to slightly inhibit the cytochrome $P_{450}$ activity, but ISS and LPS showed significantly the inhibitory effect on cytochrome $P_{450}$. The hsp70 expression began to increase after treatments and showed high induction at 6 hour, followed by zero level at around 12 hour. The quantity of the hsp70 expressed by elutriate treatments of PMC, AFPS, MSS, ISS, and LPS was 1.9, 3.0, 3.3, 4.4, and 4.7 fold higher than that of distilled water. These results indicate that in toxicity tests of five organic waste materials, four kinds of sludge materials appeared more toxic than PMC. Results of AChE, P450, and hsp70 of earthworm might be useful for expecting or assessing an effect by exposure of organic wastes to earthworms in soil.

• Journal of Korean Society on Water Environment
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• v.22 no.3
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• pp.462-467
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• 2006

An improvement of nitrogen and phosphorus removal in SBR using the elutriated acids from the food waste as an external carbon source was investigated in this study. The food waste was elutriated at $35^{\circ}C$ and pH 9 to produce the external carbon source. The elutriate of food waste were continuously collected. The elutriated liquid contained VFAs of 39,180 mg/L representing soluble COD of 44,700 mg/L. The SBR showed poor denitrification and EBPR (enhanced biological phosphorus removal) without elutriated VFAs addition. An average denitrification rate was 0.4 mg NOx-N/g MLVSS/day. In turn, EBPR was also inhibited by this poor denitrification because the remaining nitrate in anaerobic phase resulting a poor denitrification. On the other hand, the denitrification in anoxic phase significantly improved with an elutriated VFAs addition. Nitrate removal was 82% while the denitrification rate was 2.9 mg NOx-N/g MLVSS/day with 18.4 mL/cycle of elutriated VFAs. With the enhanced denitrification, nitrate concentration in anaerobic phase could effectively be controlled to a very low level. The elimination of nitrate inhibition in anaerobic phase resulted enhancement of EBPR. The specific phosphate release rate was $1.9mg\;PO_4^{3-}-P/g\; MLVSS/day$ with less than 0.5 mg/L of $PO_4^{3-}-P$ concentration.