• Magazine of the Korean Society of Agricultural Engineers
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• v.40 no.4
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• pp.77-84
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• 1998

Adsorption and leaching characteristics of the artificial soils produced from water and wastewater treatment sludges were examined. The batch adsorption test and TCLP leaching test were used, and constituents of interest were heavy metals and nutrients. As, Cr, Cu, Pb, and Cd were analyzed for metals, and nitrogen and phosphorus were analyzed for nutrients. All the artificial soils showed strong adsorption and low leaching for the heavy metals, which implies that the artificial soils may not be hazardous to the environment due to heavy metals and even they can be utilized effectively to remove metals in solution like mine and industrial wastewaters. This is quite promising result because in most case heavy metals are the most concern in the application of sludge product to the farmland. For the nutrients, generally, artificial soils showed high adsorption and low leaching except artificial soil from wastewater sludge produced by low temperature firing. The artificial soils produced from water treatment sludge were active in adsorbing nutrients and showed low leaching that they can be practically used to remove nutrients in advanced treatment process of the wastewater. The artificial soils produced from wastewater treatment sludge were less active in adsorbing nutrients and showed high teaching. However, they could be used usefully if applied properly to the plant growing because of their fertilizing effect. Based on the test results, overall, the artificial soils were thought to be not hazardous to the environment and they could be more useful if applied properly.

• Journal of Environmental Science International
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• v.19 no.10
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• pp.1203-1210
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• 2010

To obtain the risk assessment of hazardous materials in ginseng, the residues of heavy metals and organochlorine pesticides in samples on the Yeungju and Sangju are surveyed. Cd and Hg in ginseng on Yeungju and Sangju is not detected. 0.21 mg/kg of As, 0.39 mg/kg of Cr, 0.14 mg/kg of Pb, 1.83 mg/kg of Cu, 3.93 mg/kg of Zn and 0.43 mg/kg of Ni in ginseng on Sangju are shown. 0.25 mg/kg of Cr, 0.08 mg/kg of Pb, 1.11 mg/kg of Cu, 8.99 mg/kg of Zn and 1.15 mg/kg of Ni in ginseng on Yeungju are detected. As and Pb in ginseng on Sangju are 7.0% and 2.8% for Korea Food & Drug Administration(KFDA) advisory level, respectively. Pb in ginseng on Yeongju are 1.6% for Korea Food & Drug Administration(KFDA) advisory level. The heavy metals such as AS, Cr, Cd, Pb, Cu, Zn, Hg, Ni in soil on Yeongju and Sangju are range of 0-20% for with Korea Food & Drug Administration (KFDA) level. BHC isomer, DDT isomer and endosulfan isomer are not detected in ginseng and soil on Yeongju and Sangju, respectively. Finally, the assessment of hazardous materials of the heavy metals and organochlorine pesticides in ginseng on the Youngju and Sangju are verified the safety the level compare with tolerances level for Korea.

• Journal of Korean Society for Atmospheric Environment
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• v.24 no.5
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• pp.574-583
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• 2008

The results of HAPs emission data using TRI (Toxic Release Inventory), SODAM (Source Data Management system) were investigated and the emissions of 7 heavy metals from their sources and emission processes were also analyzed. Questionnaire for source data analysis as well as the stack sampling were carried out for 17 factories among 6 selected industrial types. The annual amount of emissions was estimated based on the measured concentration and flow rates. All sources were operated with high efficiency control devices and the concentration levels of all heavy metals were shown to be below 0.1 to of regulation standard. The highest emission source of heavy metals was steel manufacturing industry with the annual emission of 342.9 kg/yr and followed by hazardous waste incinerator, paint manufacturing, nonferrous metal manufacturing, rolling & press goods manufacturing and storage battery manufacturing. In the case of Hg, the emissions were quite significant from electric acros of steel manufacturing industry, although the concentration level was below the emission standard, showing the necessity of specific care for its management.

• Journal of Environmental Health Sciences
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• v.19 no.2
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• pp.46-54
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• 1993

This study was carried out on the stabilized/solidified treatment for the reducing leachability of hazardous heavy metals copper, lead, chromium and cadmium in the hazardous sludge which treated to be unleached heavy metals by sodium diethyl dithiocarbamate. Cement matrix was analyzed for the leachability of 24 hrs and dynamic leaching test, structure and the optimum condition for the stabilization and solidification of the hazardous sludge. In 28 days of curing time the unconfined compressive strength was 21.5 kg/cm$^2$ at the ratio of portland cement (0.5)+fly ash (0.25) and 23.5 kg/cmz at the ratio of portland cement (0.5)+fly ash (0.25) + cake (0.25). High concentration of Pb, Cr and Cd in the sea water and Cu in the distilled water were leached at the dynamic leaching test. The concentration of leaching heavy metals for specimens which were tested 24 hrs were found low leachability with decreasing pH of leachant. According to dynamic leaching test, the low level of copper, lead, cadmium and chromium were leached in the cement matrix with sodium diethyl dithiocarbamate. But the effective diffusion coefficient of unleached cement matrix which was treated sodium diethyl dithiocarbamate was decreased above 2 times than that of cement matrix. The relation of leachant renewal period (Y) and cumulative fraction ion leached (X) was the following regression equations. Solidification with unleached agent. Y$_{Cu}$ = 1413752X + 247, Y$_{Pb}$ = 223501IX + 214, Y$_{Cr}$ = 8310601X - 472, Y$_{Cd}$ = 168787X + 1061 The structure of' solidified matrix with X-ray diffraction analysis was composed more Ca(OH)$_2$, Si, Mg(OH)$_2$ and Al in the unleached cement matrix than those in cement matrix.

• Journal of Food Hygiene and Safety
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• v.15 no.4
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• pp.324-327
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• 2000

The analysis of hazardous heavy metals, such as Pb, Cd and As, was conducted from the porcelain dinnerwares. Total 374 samples of those products in the domestic market were purchased for the study. All the samples were extracted by 4% acetic acid solution, followed by the analysis with AAS(Atomic Absorption Spectroscopy). As a result, Pb and As were detected maximum 8.63$\mu\textrm{g}$/ml, 2.58 ng/ml, respectively. Cd was fecund in a sample as 0.10$\mu\textrm{g}$/ml.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.49 no.5
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• pp.556-563
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• 2016

We examined the removal of hazardous heavy metals (Cd, Cr, and Pb) from laver Pyropia sp. using citric, hydrochloric, and nitric acids. Under the same conditions, the quality of the laver samples was also evaluated using the variation in absorbance and major mineral levels. The heavy metals that accumulated in raw laver samples after 3 days in seawater included Pb (117.79 μg/g), Cr (33.53 μg/g), and Cd (10.54 μg/g) in descending order. The rate of heavy metal removal from laver was higher at lower pH for all acids used. However, its color changed unsatisfactorily at pH 2.0. After 10 min in seawater at pH 2.5, the heavy metals in laver were eliminated in the order Cd (68.7–81.6%), Pb (57.7–67.0%), and Cr (31.9–49.4%) using the three acids. The differences in heavy metal removal among acid types were not significant. The laver quality was not affected after 20 min at the pH range of 2.5–4.0. The maximum removal of heavy metals was from laver soaked for 10 min in seawater at pH 2.5 using the organic acid, citric acid.

• Journal of Korean Society for Atmospheric Environment
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• v.15 no.3
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• pp.235-247
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• 1999

This study was performed to investigate what was the most serious occupational factors in small scale industries. Twenty-three occupatonally hazardous substances were measured at the five workplaces in the Eastern Seoul during 1995∼1996. Total of 2,020 samples were analyzed by either GC/FID for organic vapors or AAS for heavy metals. From the results of this study noise was the most serious factor at the selected workplaces. Noise level in the metal processing, the printing, and the auto repairing industries exceeded the 8 hr PEL by 19.7%, 13.6%, and 11.6%, respectively. Mean concentrations of toluene in the shoe making and the printing industries exceeded the assessment crieterion by 6.0% and 3.8%, respectively. Further study of risk assessment of occupational exposure may be required to protect workers from hazardous working conditons.

• Journal of the Korean Society of Clothing and Textiles
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• v.28 no.1
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• pp.165-171
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• 2004

The analytical method of toxic heavy metals in disposable diapers was developed. Disposable diapers obtained from Korea, Japan, America and German were determinated and quantified. Sample treatment (Total Digestion) was wet chemical acid digestion for extraction of nine hazardous inorganic elements (Sb, As, Pb, Cd, Cr, Co, Cu, Ni, Hg) in disposable diapers. Inductively Coupled Plasma Mass Spectrometer (ICP-MS) and Inductively Coupled Plasma Atomic Emission Spectrometer (ICP-AES) have been used for analyzing nine hazardous inorganic elements. The results were as follows : The concentration of extractable Sb which was treated for 3 hours with artificial urine and disposable diapers was higher than those of 6 hours and 24 hours. The concentration of extractable Cr was same as Sb. On the other hands, the behavior of Cu and Ni were different from Sb and Cr. Concentrations of extractable Cu and Ni increased as increasing the reaction time between artificial urine and disposable diapers.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.28 no.4
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• pp.393-405
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• 2018

Objective: This study examines the types of hazardous factors in the working environment and the time-trend for their exposure levels over 10 years (2007 to 2016). Study Design and Method: The types of hazardous factors and exposure levels were drawn from the 19 measurement reports on the working environment over 10 years at a shock absorber manufacturing facility. Risk assessment of the types of factors and time-trend of exposure levels were evaluated using the factors and exposure levels. Results: A total of 34 hazardous factors were evaluated. The types were noise, 15 organic compounds, seven kinds of acid sand alkalis, eight kinds of heavy metals, and three other compounds. Special management materials used were nickel, hexavalent chrome, and sulfuric acid. Human carcinogens (1A) used were trichloroethylene, nickel, and sulfuric acid. There were six types of substances belonging to the IARC's 2B (body carcinogens) classification or higher, including, methyl isobutyl ketone, ethyl benzene, and trichloroethylene. No detection was found for 627 out of the 2065 total measurements in 19 exposure survey reports, representing 30.4%. Organic solvents, acid and alkali products, and heavy metals showed continuous low exposure concentrations. Noise, welding fumes, and the evaluation of mixed solvents show a gradual decrease in geometric mean and maximum over the time-trend of 10 years. Conclusions: In the case of a shock absorber manufacturing facility, the hazardous factors of noise and the evaluation of mixed solvents still indicate high concentrations exceeding the exposure limits and necessitate reduction studies. These two factors and welding fumes showed a continuous decrease in their ten-year tendency. Organic compounds, acids/alkalis, and heavy metals were managed smoothly in a work environment of continuous low concentrations.

• Journal of Sasang Constitutional Medicine
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• v.22 no.3
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• pp.132-140
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• 2010

1. Objective: To compare the contents and transfer rate of hazardous substances in crude, washing solution, crude after washing, decoction and remnant after boiling. 2. Methods: The heavy metal contents of each step were measured by inductively coupled plasma mass spectrometer (ICP-MS) and mercury analyzer (MA-2). In order to analyze pesticides in each sample we used simultaneous multi-residue analysis of pesticides by GC/ECD, which was followed by GC/MSD analysis to confirm the identity of the detected pesticide in each sample. In addition, the contents of sulfur dioxide (SO2) were performed by Monier-Williams distillation method. 3. Results: 1) Contents (mg/kg) of heavy metals in decoction of all herbal medicine prescriptions were not detected. 2) Transfer rates (%) of heavy metals from crude to remnant were As (83.3%), Cd (100.0%), Pb (182.6%) and Hg (100.0%). 3) Contents (mg/kg) of residual pesticides were not detected. 4) Transfer rate (%) of sulfur dioxide (SO2) from crude to remnant was 44.2%. 4. Conclusion: Our results showed that boiled herbal medicine prescriptions which we take is safe from the hazardous substances.