• Korean Journal of Soil Science and Fertilizer
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• v.44 no.1
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• pp.38-47
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• 2011

This study focused on health risk assessment via multi-routes of As exposure to establish a target cleanup level (TCL) in abandoned mines. Soil, ground water, and rice samples were collected near ten abandoned mines in November 2009. The As contaminations measured in all samples were used for determining the probabilistic health risk by Monte-Carlo simulation techniques. The human exposure to As compound was attributed to ground water ingestion. Cancer risk probability (R) via ground water and rice intake exceeded the acceptable risk range of $10^{-6}{\sim}10^{-4}$ in all selected mines. In particular, the MB mine showed the higher R value than other mines. The non-carcinogenic effects, estimated by comparing the average As exposure with corresponding reference dose were determined by hazard quotient (HQ) values, which were less than 1.0 via ground water and rice intake in SD, NS, and MB mines. This implied that the non-carcinogenic toxic effects, due to this exposure pathway had a greater possibility to occur than those in other mines. Besides, hazard index (HI) values, representing overall toxic effects by summed the HQ values were also greater than 1.0 in SD, NS, JA, and IA mines. This revealed that non-carcinogenic toxic effects were generally occurred. The As contaminants in all selected mines exceeded the TCL values for target cancer risk ($10^{-6}$) through ground water ingestion and rice intake. However, the As level in soil was greater than TCL value for target cancer risk via inadvertent soil ingestion pathway, except for KK mine. In TCL values for target hazard quotient (THQ), the As contaminants in soil did not exceed such TCL value. On the contrary, the As levels in ground water and polished rice in SD, NS, IA, and MB mines were also beyond the TCL values via ground water and rice intake. This study concluded that the health risks through ground water and rice intake were greater than those though soil inadvertent ingestion and dermal contact. In addition, it suggests that the abandoned mines to exceed the risk-based TCL values are carefully necessary to monitor for soil remediation.

• Journal of Ginseng Research
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• v.22 no.2
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• pp.122-125
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• 1998

Adequate available soil moisture level is considered to be one the most important components in growing high yields of good quality ginseng. Excessive soil moisture may promote stillborn fungal pathogens and cause serious diseases in ginseng fields. This study showed that soil moisture levels for optimum growth and health of ginseng varied with soil texture. Fifty- percent available moisture for sandy loam and 75% for silty loam are the best moisture levels for good growth and higher yield.

• Journal of environmental and Sanitary engineering
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• v.22 no.3
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• pp.35-50
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• 2007

In order to investigate water pollution of spring, we carried out the experiments on mineral water, rainwater and surrounding soil of several springs collected in Incheon area from February to August in 2007. The results were as follows. 1. Soil : This study investigated the pH and organic matter contents in the soil which effect on microorganisms. The pH value was from 4.5 to 5.3 on average and organic matter contents ranged from 1.09% to 5.6% and E. coli, K. pneumoniae, S. faecalis and other microorganisms were isolated. 2. Natural mineral water : As the rainfall increased, the concentration of $No_3-N$, consumption of $KMnO_4$ and the number of microorganisms was increased while the other physicochemical items were not affected. The microorganism isolated in the natural mineral water were as follows: E. coli, K. oxytoca S. faecalis, S. facium, and so on from evacuation; E. agglomerans, E. amnigenus, E. cloacae, E. sakazakii and so on from the environments and evacuation. Detection of these microorganisms shows that the environment around the spring had been exposed to excrements of the warm blood animal. 3. Rain : The coliforms in the rain were the identical one detected from the mineral water and the soil. In conclusion the quality of natural mineral water is influenced by rain, resident bacteria of soil and surrounding environment. This study will be the basic data of characteristics of spring in Incheon area and also this result will give useful aids for the efficient control of spring.

• Journal of Soil and Groundwater Environment
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• v.27 no.2
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• pp.50-60
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• 2022

The concentration levels and distribution characteristics of 16 polycyclic aromatic hydrocarbons (PAHs) were investigated and evaluated for total 100 soil samples as a part of the survey on soil contamination in Gwangju. The results (median and range) of T-PAHs (sum of 16 PAH concentrations), C-PAHs (sum of carcinogenic PAH concentrations) and T-TEQs (sum of 16 TEQ concentrations) were 20.8 (7.6~1158.1), 2.2 (N.D~509.6), and 0.3 (N.D~424.6) ㎍/kg, respectively. There was a positive correlation between C-PAHs/T-PAHs and T-TEQs/T-PAHs except one point where the concentration of benzo(a)pyrene was high. The ratios of the C-PAHs/T-PAHs were 31.7% for low molecular weight-PAHs and 68.3% for high molecular weight-PAHs, suggesting that PAHs generation mainly arose from combustion sources. The ratio of isomers of individual PAHs, Phe/Ant, Flu/Pyr, Ant/(Ant+Phe), Flu/(Flu+Pyr), and BaA/(BaA+Chr), also confirmed the predominance of PAHs from combustion activities. Statistical tracing of the source of PAHs through principal component analysis indicated that the main sources of combustion were automobile fuel and coal. The overall results of this study suggested HMW-PAHs, T-PAHs, C-PAHs and T-TEQs should be separately evaluated to better assess the toxicity and environmental behavior of individual PAHs.

• Journal of Environmental Health Sciences
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• v.47 no.2
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• pp.155-165
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• 2021

Objectives: Acute exposure to high concentrations of chemicals can occur when a chemical accident takes place. As such exposure can cause ongoing environmental pollution, such as in the soil and groundwater, there is a need for a tool that can assess health effects in the long term. The purpose of this study was assessing the health risks of residents living near a chemical accident site due to long-term exposure while considering the temporal concentration changes of the toxic chemicals leaked during the accident until their extinction in the environment using a multimedia environmental dynamics model. Methods: A health risk assessment was conducted on three cases of formaldehyde chemical accidents. In this study, health risk assessment was performed using a multimedia environmental dynamics model that considers the behavior of the atmosphere, soil, and water. In addition, the extinction period of formaldehyde in the environment was regarded as extinction in the environment when the concentration in the air and soil fell below the background concentration prior to the accident. The subjects of health risk assessment were classified into four groups according to age: 0-9 years old, 10-18 years old, 19-64 years old, and over 65 years old. Carcinogenic risk assessment by respiratory exposure and non-carcinogenic risk assessment by soil intake were conducted as well. Results: In the assessment of carcinogenic risk due to respiratory exposure, the excess carcinogenic risk did not exceed 1.0×10-6 in all three chemical accidents, so there was no health effect due to the formaldehyde chemical accident. As a result of the evaluation of non-carcinogenic risk due to soil intake, none of the three chemical accidents had a risk index of 1, so there was no health effect. For all three chemical accidents, the excess cancer risk and hazard index were the highest in the age group 0-9. Next, 10-18 years old, 65 years old or older, and 19-64 years old showed the highest risk. Conclusion: This study considers environmental changes after a chemical accident occurs and until the substance disappears from the environment. It also conducts a health risk assessment by reflecting the characteristics of the long-term persistence and concentration change over time. It is thought that it is of significance as a health risk assessment study reflecting the exposure characteristics of the accident substance for an actual chemical accident.

• Korean Journal of Soil Science and Fertilizer
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• v.47 no.5
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• pp.362-367
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• 2014

This study was performed to test the applicability of the ozone/hydroxy radical reaction system, which applied advanced oxidation processes, to remove total petroleum hydrocarbon (TPH) from the fine soil in washing water of the soil washing process. Removal efficiency was tested on 40 L of washing water in a pilot reaction tank. Fine soil contaminated with $800mg\;kg^{-1}$ TPH was prepared at 5% and 10% suspended solids. Testing conditions included ozone/hydroxy radical flow rates of 40, 80, and $120L\;min^{-1}$, and processing time of 2 to 12 hours. The removal efficiency of petroleum hydrocarbon from water waster by ozone/hydroxy radical was increased with higher flow rates and lower percentages of suspended solids. Optimal efficiency was achieved at $80L\;min^{-1}$ flow rate for 4 hours for the 5% suspended solids, and $120L\;min^{-1}$ for 6 hours for the 10% suspended solids. These results verified the efficiency of hydroxy radical in removing TPH and the applicability of the ozone/hydroxy radical reaction system in the field.

• Journal of the Korean Society of School Health
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• v.21 no.2
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• pp.89-95
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• 2008

Purpose: The purpose of this study is to investigate the heavy metal pollution of playgrounds of elementary schools in the Ulsan Metropolitan City. Soil pollution is one of the most dangerous problems of the utmost concern to both children and teachers. The result of this study would be an educational datum for improving children's health and establishing educational policy. Methods: For the analysis, fifteen representative schools were selected from five sample areas such as Dong-gu, Nam-gu, Jung-gu, Buk-gu and Ulju-gun of the Ulsan city. And from each school playground, soil was extracted from five spots and mingled into one sample. These fifteen samples were pretreated by the microwave extraction method, and the extracted heavy metals(As, Cd, Cu, Pb, Cr⁶⁺, Zn and Hg) were quantified by the ICP(Inductively Coupled Plasma) system. Results: The results of the analysis shows that the level of heavy metal pollution of elementary school playgrounds in Ulsan city did not exceed the permitted limit of each heavy metal. This means that the soil pollution of playgrounds in the Ulsan Metropolitan City is not so serious as it is expected. But it should be added that the soil is not too safe to be ignored.

• Proceedings of the Korean Environmental Health Society Conference
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• 2001.11a
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• pp.11-16
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• 2001

If microorganisms are injected into porous medium such as soils along with appropriate substrate and nutrients, soil pore size and shape are changed from the initial condition as a result of biofilm formation, which make hydraulic conductivity reduced. In this research, hydraulic conductivity reduction was measured after specific bacterium or fungus was inoculated into soil pore. Hydraulic conductivity was decreased to 10 % ∼ 1 % and maintained constant while substrate was provided. Under the adverse conditions such as no substrate, chemical solution permeation, and freeze-thaw cycles, hydraulic conductivity was increased 30∼50%. Hydraulic conductivity decrease of fungus-soil mixture was faster than that of bacterium-soil mixture. Fungus-soil mixture, however, was more sensitive to the adverse conditions.

• Korean Journal of Environmental Agriculture
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• v.32 no.4
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• pp.245-251
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• 2013

BACKGROUND: The objectives of this study are to investigate the contamination levels of heavy metals in soil, ground water, and agricultural product near the abandoned Boeun and Sanggok mine areas in Korea and to assess the health risk for these local residents exposed to the toxic heavy metals based on analytical data. METHODS AND RESULTS: By the results of human health risk assessment for local residents around Boeun and Sanggok, human exposure to cadmium, copper, arsenic from soil and to lead, cadmium, and arsenic from rice grain were higher in Sanggok, but human exposure to zinc and arsenic from ground water was higher in Boeun. By the results of hazard index (HI) evaluation for arsenic, cadmium, copper, lead, and zinc, HI values in both areas were higher than 1.0. This result indicated that the toxicity hazard through the continuous exposure to lead, cadmium, arsenic from rice, ground water, and soil would be likely to occur to the residents in the areas. Cancer risk assessment for arsenic, risks from the rice were exposed to one to two out of 10,000 people in Boeun and one of 1,000 people in Sanggok. These results showed that the cancer risks of arsenic in both areas were 10~100 times greater than the acceptable cancer risk range of US EPA ($1{\times}10^{-6}{\sim}1{\times}10^{-5}$). CONCLUSION(S): Therefore, if these two local residents consume continuously with arsenic contaminated soil, ground water, and rice, the adverse health effects (carcinogenic potential) would be more increased.

• Journal of Environmental Health Sciences
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• v.24 no.3
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• pp.63-69
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• 1998

The treatment of soils and water contaminated with MTBE using the Fenton oxidation was investigated. The effects of dosage of $H_{2}O_{2}$, and Fe$^{2+}$ concentrations, and solution pH on transformation and mineralization in soil were evaluated. Generation of TBA and acetone following Fenton-oxidation of MTBE in water and generation of acetone following Fenton-oxidation of TBA were observed. Therefore TBA and acetone are degradation intermediates of MTBE. There was a large difference of treatment efficiency in Fenton oxidation of MTBE between soil and water system. This may be caused by the complex nature of soil, soil organic matter which can consumed OH $\cdot$ radicals, and interacting with inorganic-soil constituents. The pH of soil was observed to have a significant effect on the chemical oxidation efficient of MTBE in soil The data demonstrated that optimal pH range were pH 3~4 and around 6. The soil batch studies demonstrated that treatment efficiency of MTBE was enhanced by adding additional ferrous salts but Fenton-oxidation occurred in no additional iron which indicated that iron in soil can catalyze the Fenton-oxidation. The most effective parameter of Fentonoxidation was $H_{2}O_{2}$/Fe$^{2+}$ ratio which theocratical ratio is 0.5. The optimal range of this ratio was found to be 0.6~2.3. In evaluating effect of $H_{2}O_{2}$ dosage on treatment efficiency, the increase of $H_{2}O_{2}$ did not always lead to increase of decompositions of MTBE in soil. Fenton oxidation was effective in destroying MTBE in aqueous extracts of contaminated soil and water. Experimental data provided evidence that the Fenton oxidation can effectively remediate MTBE-contaminated water and soil.