• Korean Journal of Soil Science and Fertilizer
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• v.40 no.1
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• pp.51-56
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• 2007

The toxicities of contaminated soils with 8 consecutive year applications of three levels (12.5, 25.0, and $50.0t\;dry\;matter\;ha^{-1}yr^{-1}$) of four organic sludge [municipal sewage sludge (MSS), industrial sewage sludge (ISS), alcohol fermentation processing sludge (AFPS) and leather processing sludge (LPS)] on earthworm (Eisenia fetida) were examined by using microcosm container in the laboratory. Results were compared with those of pig manure compost (PMC) treated soil. In tests with three treatment levels (12.5, 25.0, and 50.0 t per plot), ISS treated soil showed higher contents of Cu (18.9~26.2 fold), Cr (7.7~34.7 fold), and Ni (14.8~18.8 fold) at 8 years post treatment, than PMC treated soil. LPS treated soil showed higher contents of Cr (35.7~268.0 fold) and Ni (4.5~7.6 fold) than PMC treated soil. There were no great differences in heavy metal contents among MSS, AFPS, and PMC treated soils. In these contaminated soils, earthworm mortalities of MSS and AFPS treated soils at 8 weeks post-exposure were similar to those of PMC treated soil regardless of each treatment level. Toxic effect (26.7~96.7 mortality) on the ISS and LPS treated soils was significantly higher than one of PMC treated soil, with an exception of LPS soil treated with 25.0 t per plot. At 16 weeks post-exposure, earthworm mortalities of AFPS' 12.5 and 25.0 t treated soils were similar to those of PMC treated soil. Toxic effect (53.3~100 mortality) on the 12.5, 25.0, and 50.0 t treated soils of MSS, ISS and LPS, and AFPS' 50.0 t treated soils was significantly higher than those of PMC treated soil. The data suggested that the 12.5, 25.0, and 50.0 t of MSS, ISS and LPS, and AFPS' 50.0 t treated soils were evaluated to have toxicity on earthworm.

• Journal of the Korea Organic Resources Recycling Association
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• v.4 no.2
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• pp.55-62
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• 1996

The purpose of this study is the evaluation of adsorption capacity of casts for heavy metals comparing with the activated carbon. The casts was obtained from vermicomposting of the mixed organic sludges which were generated from the treatment facilities for leather wastewater and cattle wastewater. The physico-chemical characteristics of cast was investigated. Also, the batch adsorption experiments of cast and activated carbon for heavy metals were carried out, and the results were analyzed by Freundlich isotherm. The buffering capacity to the acidic wastewater was founded in the cast, and the cation exchange capacity of cast impling adsorption capacity for soluble substances was evaluated as about 55me/100g. Those were implied that the cast have a large potential as a good adsorbent for soluble pollutants in wastewater. From the results of batch experiments, the removal efficiencies of tested various heavy metals including Pb, Cu, Cd, and Cr were very high value as 89-98% for the activated car-bon, and 80~95% for the casts except for Zn. The adsorption equilibriums for the two materials were achieved within 90 minutes. The order of preferable metals in the adsorption was found to be Pb>Cu>Cd>Cr>Zn on the cast and to be Pb>Cd>Cu>Cr>Zn on the activated carbon, respectively. From the above results, it might be con-cluded that cast is effectively available as a good adsorbent to treating the heavy metal bearing wastewater.

• Journal of the Korean Society for Marine Environment & Energy
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• v.9 no.3
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• pp.160-167
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• 2006

Harpacticoid copepod Tigriopus japonicus is widely distributed in coastal waters of Korea and plays important role in marine trophic structure as a first consumer. In this study, a series of experiment were conducted to test the potential of the species as a standard test species for marine bioassay. Tolerance on salinity and pH, sensitivity on the reference materials(copper sulfate and cadmium chloride) and response on the ocean dumping materials(waste sludge) we re tested to identify if the species satisfy the basic criteria as standard species for marine bioassay. The nauplius of the species($100{\sim}200{\mu}m$) showed wide tolerance on salinity with >90.0% survival rates exposed to $5.0{\sim}35.0psu$ for 48 h. Wide adaptability on pH's were also observed from 6.3 to 8.2 with >90.0% survival rates during the test. $LC_{50}$ values for copper sulfate and cadmium chloride were $3.6{\pm}0.7ppm,\;1.7{\pm}0.8ppm$, respectively. The variations in mortality between replicates were less than 10.0%. Comparison of $LC_{50}$ values indicated that T. japonicus nauplius was lower sensitive to copper sulfate than the most marine crustaceans included copepods, however, the sensitivity of test animal to cadmium chloride higher than the adults of copepod T. japonicus, Paracalanus parvus, and marine rotifer Brachinonus plicatilis. There were significant concentration-response relationship in the mortality of T. japonicus nauplius using the elutriates of three ocean dumping materials(industrial waste sludge). 48 h $LC_{50}$ values we re $31.1{\pm}1.1%$ for the elutriate of sludge from leather processing company and $54.4{\pm}15.1%$ for that of dye production company. Based on the above experimental results, bioassay using benthic harpacticoid T. japonicus nauplius must be a good estimation tool for marine ecotoxicological assessment of waste or chemicals. Wide tolerance on the salinity and pH, and significant linear relationship between concentration and response(mortality) supported the high potential of the species as a standard test species.