• Journal of Environmental Impact Assessment
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• v.25 no.6
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• pp.414-431
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• 2016

There are numerous closed and abandoned mines in Korea, from which diverse heavy metals (e.g., As, Cd, Cu, Pb, Zn) are released into the surrounding soil, groundwater, surface water, and crops, potentially resulting in detrimental effects on the health of nearby residents. Therefore, we performed human risk assessments of two abandoned metal mines, Yanggok (YG) and Samsanjeil (SJ). The exposure parameters used in this assessment were specific to residents near mines and the included exposure pathways were relevant to areas around metal mines. The computed total excess carcinogenic risks for both areas exceeded the acceptable carcinogenic risk ($1{\times}10^{-6}$), indicating that these areas are likely unsafe due to a carcinogenic hazard. In contrast, the non-carcinogenic risks of the two areas differed among the studied receptors. The hazard indices were higher than the unit risk (=1.0) for male and female adults in YG and male adults in SJ, suggesting that there are non-carcinogenic risks for these groups in the study areas. However, the hazard indices for children in YG and female adults and children in SJ were lower than the unit risk. Consumption of groundwater and crops grown in the area were identified as major exposure pathways for carcinogenic and non-carcinogenic hazards in both areas. Finally, the dominant metals contributing to carcinogenic and non-carcinogenic risks were As and As, Cu, and Pb, respectively. In addition, the carcinogenic and non-carcinogenic risks of YG were evaluated to be 10 and 4 times higher than those of SJ, respectively, resulted from the relatively higher exposure concentration of As in groundwater within SJ area. Because of lacking of several exposure parameters, some of average daily dose (ADD) could not be computed in this study. Furthermore, it is likely that the ADDs of crop-intake pathway included some errors because they were calculated using soil exposure concentrations and bioconcentration factor (BCF) rather than using crop exposure concentrations.

• Journal of Food Hygiene and Safety
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• v.29 no.3
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• pp.189-194
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• 2014

This study was conducted to evaluate microorganism contamination of food utensils and service facilities in school and to prevent hazards by food poisoning occurrence. As a result, the highest number of microorganism growth plate ($12.3{\pm}2.6$) was detected in total bacteria test plate, and also observed $10.3{\pm}3.9$ growth plates in Staphylococcus aureus test plate and $9.5{\pm}3.9$ growth plates in E. coli and coliform bacteria test plate. But we could detect to the lowest number of growth plates ($1.5{\pm}1.0$) in Vibrio test plate. We also assessed that floors were appeared to the highest microorganism contamination rate in food utensils and service facilities. Therefore, $4.5{\pm}0.6$ growth plates was detected in pre-operation floor and $4.3{\pm}1.0$ growth plates in floor. And high level of microorganism contamination also observed in tables as $3.3{\pm}1.0$ growth plates in cooking table and $3.0{\pm}0.0$ growth plates in dining table. The level of microorganism contamination of food utensils such as kitchen knife, cutting board, and food tray were lower than that in food service facilities. We analysed microorganism contamination according to purpose of use in kitchen knifes and cutting boards. The microorganism contamination rate in fish kitchen knife ($2.0{\pm}0.8$) and fish cutting board ($1.3{\pm}1.5$) were slightly higher than that of others purpose of use. As a result of microorganism identification, various strains of microorganism were contaminated in food service facilities and some strains could detected more than two times. Especially, Staphylococcus aureus was repeatedly identified in cooking table, trench, and kitchen knife. Bacillus cereus was identified in kitchen knife, and then Pseudomonas fluorescens and Pseudomonas aeruginosa were also detected in food utensils and service facilities as known to food spoilage microorganisms. Klebsiella pneumoniae was detected four times repeat, which widely distribute natural environment as normal bacterial flora but sometimes cause acute pneumonia. These results suggest that food utensils and service facilities are contaminated with not only major food poisoning microorganisms such as Staphylococcus aureus, but also food spoilage microorganisms. Taken together, strict personal hygiene control and efficient food service facilities management will be needed to enhance food safety in school feeding and to improve student health.

• Journal of Preventive Medicine and Public Health
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• v.15 no.1
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• pp.145-151
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• 1982

Breslau's report on the two stillbirths induced by illuminating gas poisoning made many investigators explore the hazards. of carbon monoxide(CO) poisoning to pregnancy. The pregnant woman, her fetus, and the newborn infant have been identified to be particularly vulnerable to CO even in low concentration. Several factors, such as placental barrier, membrane resistance of maternal and fetal red blood cells etc., were considered to be related to the delayed elimination of CO from fetus. Slower elimination of CO from fetus than from mother was confirmed in several in vivo studies. But there are few studies which have confirmed the difference of carboxyhemoglobin (HbCO) dissociation in adult and fetal bloods. Author investigated the effects of hemoglobin itself on the elimination of CO from mother and fetus. By observing the difference of CO dissociation from adult and fetal hemoglobin at the various partial pressures of oxygen, the author tries to suggest the base of the proper treatment measure for the CO poisoning of pregnant woman and newborn infant. The results were as follows: 1. The total hemoglobin amounts of adults and fetal bloods were $16.1{\pm}0.50gm%\;and\;15.7{\pm}0.32gm%$, respectively. The fetal hemoglobin proportions in adult and fetal bloods were $1.2{\pm}0.15%\;and\;72.7{\pm}3.01%$, respectively. 2. Adult and fetal bloods saturated by CO to 100% HbCO were exposed to ambient air$(21%\;O_2),\;100%\;O_2\;and\;3\;ATAO_2$. After 30 minutes exposure, the HbCO saturations of adult blood were 96.7%, 70.9%, and 52.8%, respectively, and those of fetal blood were 98.5%, 76.1%, and 62.2%, respectively. HbCO dissociation was proportional to the partial pressure of oxygen and the most marked dissociation was shown under 3 ATA $O_2$, HbCO dissociation of fetal blood was slower than that of adult blood in all conditions. According to the above results, it is possible that CO poisoning make more serious damage to the fetus and newborn infant than to the adult due to the delayed dissociation of HbCO. Thus in the treatment of CO poisoning of pregnant woman and newborn infant, hyperbaric oxygen therapy seems to be the most eflective treatment measure, but the duration of hyperbaric oxygenation should be lengthened accordingly.

• Korean Journal of Soil Science and Fertilizer
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• v.37 no.3
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• pp.177-183
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• 2004

The discharge of waste nutrient solution from greenhouse to natural ecosystem leads to the accumulation of excess nutrients that results in contamination or eutrophication. There is a need to recycle the waste nutrient solution in order to prevent the environmental hazards. The amount and kind of nutrients in waste nutrient solution might be enough to grow photosynthetic microorganisms. Hence in the present study, we examined the growth and mass cultivation of cyanobacteria in the waste nutrient solution with an objective of removing N and P and concomitantly, its mass cultivation. Four photosynthetic filamentous cyanobacteria (Anabaena HA101, HA701 and Nostoc HN601, HN701) isolated from composts and soils of the Chungnam province were used as culture strains. Among the isolates, Nostoc HN601 performed faster growth rate and higher N and P uptake in the BG-II ($NO_3{^-}$) medium when compared to those of other cyanobacterial strains. Finally, the selected isolate was tested under optimum conditions (airflow at the rate of $1L\;min^{-1}$. in 15 L reactor, initial pH 8) in waste nutrient solution from tomato hydroponic in green house condition. Results showed to remove 100% phosphate from the waste nutrient solution in the tomato hydroponics recorded over a period of 7 days. The growth rate of Nostoc HN601 was $16mg\;Chl-a\;L^{-1}$ in the waste nutrient solution from tomato hydroponics with optimum condition, whereas growth rate of Nostoc HN601 was only $9.8mg\;Chl-a\;L^{-1}$ in BG-11 media. Nitrogen fixing capacity of Nostoc HN601 was $20.9nmol\;C_2H_4\;mg^{-1}\;Chl-a\;h^{-1}$ in N-free BG-11. The total nitrogen and total phosphate concentration of Nostoc HN601 were 63.3 mg N gram dry weight $(GDW)^{-1}$ and $19.1mg\;P\;GDW^{-1}$ respectively. Collectively, cyanobacterial mass production using waste nutrient solution under green house condition might be suitable for recycling and cleaning of waste nutrient solution from hydroponic culture system. Biomass of cyanobacteria, cultivated in waste nutrient solution, could be used as biofertilizer.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.5
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• pp.589-597
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• 2008

The purpose of this study is to arrange for the systematic execution of safety control in children's foods through nutrition and hygiene standard suggestions and guidelines for quality certification system in children's preferable food. Aiming to achieve this objective, the study researched the present status of children’s preferable food sold near elementary schools, elicited the hazards and problems of those foods and selected nutritional and hygienic hazard components in those foods. To suggest the standards and guidelines for quality certification in children's preferable food, the study referred to sundry records, surveyed the practical cases of relevant policies and standards at home and abroad. We studied the standard of nutrition for the quality certification in those foods for sugar, fat, sodium, and additives (tar color: red No. 2 in a ban on use, caffeine), microorganism (aflatoxin $B_1$ (${\mu}g$/kg) and pathogenic bacteria (Staphylococcus aureus, Bacillus cereus, Salmonella spp.), which are the nutrients that may hamper health when taken in a large amount, and the standard for a diet restricted to under 200 kcal per one serving size. Results of distribution of processed foods (242 samples) by nutrition standards were as follows. In case of all ‘low’ level in total sugar, total fat and sodium, 0.4% of total samples was possible to be certified, In case of all ‘medium’ level in total sugar, total fat and sodium, maximumly 22.3% of total samples was possible to be certified. In case of all medium level in nutrients and $\leq$200 kcal/serving, 17.8% of total samples was possible to be certified. Certified food types was milk products and beverages.

• Journal of Food Hygiene and Safety
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• v.24 no.1
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• pp.1-11
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• 2009

Consumers are very concerned about food safety as the risk with food increased. This study was conducted to evaluate the perceptions and practices of consumers on food safety in order to collect some information for the development of consumer education program. Total 500 consumers were asked to answer for survey constituted with 6 questions of generic information, 4 of food safety perceptions and 8 of food safety practices from June to July, 2006. More than half of respondents (51.8%) were unsatisfied with the food safety management of government while the individual practices on food safety were satisfactory. Especially, most respondents (98.7%) checked the expiration date of food when they purchased and 97% of respondents were washed hands before food preparation. The higher food safety perception, the better food safety practices of consumers. These results suggest that the systematic and continuous educations on food safety hazards and the principles of sanitation management are necessary for safe food handling and perception on food safety.

• Journal of Food Hygiene and Safety
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• v.27 no.3
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• pp.277-284
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• 2012

The objective of this study was to investigate and evaluate microbial contamination levels of leafy greens (perilla leaf and lettuce) and its distributing conditions at different seasons (Feb, May, Aug, and Nov of the year 2011) in order to provide insight into any potential health hazards associated with consumption of these commodities. Leafy greens were collected from a farm located in Geumsan, Chungnam and wholesale markets (WM) and traditional markets (TM) located in Suwon. At the same time, temperature and relative humidity fluctuations experienced by the leafy greens during distribution from the farm to the distribution center were measured by a data logger. The contamination levels of perilla leaf and lettuce were determined by analyzing total plate count. Coliform groups, Bacillus cereus, Escherichia coli, Escherichia coli O157:H7, Salmonella spp., Listeria monocytogenes and Staphylococcus aureus were determined. The contamination levels of total aerobic bacteria, coliform groups and B. cereus in both vegetables sampled during May and August found to be higher than those sampled during February and November. E. coli O157:H7, Salmonella spp., L. monocytogenes were not detected in the vegetables analyzed in this study. There were no significant trends between samples at WM and TM in the contamination levels. Relative humidity of vegetables distributed from the farm to the distribution center showed over 90% during distribution regardless of measured seasons. In the case of background microflora on leafy greens, the density was significantly increased at 20, 30 and $37^{\circ}C$ during storage of 24h. E. coli O157:H7 and B. cereus inoculated on the leaves also showed similar increases in the storage tests. The microbial contamination levels determined in this study may be used as the fundamental data for microbial risk assessment.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.62 no.4
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• pp.333-345
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• 2017

The potato tuber is known as a rich source of essential nutrients, used throughout the world. Although potato-breeding programs share some priorities, the major objective is to increase the genetic potential for yield through breeding or to eliminate hazards that reduce yield. Glycoalkaloids, which are considered a serious hazard to human health, accumulate naturally in potatoes during growth, harvesting, transportation, and storage. Here, we used the AMMI (additive main effects and multiplicative interaction) and GGE (Genotype main effect and genotype by environment interaction) biplot model, to evaluate tuber yield stability and glycoalkaloid content in six potato cultivars across three locations during 2012/2013. The environment on tuber yield had the greatest effect and accounted for 33.0% of the total sum squares; genotypes accounted for 3.8% and $G{\times}E$ interaction accounted for 11.1% which is the nest highest contribution. Conversely, the genotype on glycoalkaloid had the greatest effect and accounted for 82.4% of the total sum squares), whereas environment and $G{\times}E$ effects on this trait accounted for only 0.4% and 3.7%, respectively. Furthermore, potato genotype 'Superior', which covers most of the cultivated area, exhibited high yield performance with stability. 'Goun', which showed lower glycoalkaloid content, was the most suitable and desirable genotype. Results showed that, while tuber yield was more affected by the environment, glycoalkaloid content was more dependent on genotype. Further, the use of the AMMI and GGE biplot model generated more interactive visuals, facilitated the identification of superior genotypes, and suggested decisions on a variety of recommendations for specific environments.

• Journal of the Korea Organic Resources Recycling Association
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• v.27 no.3
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• pp.81-89
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• 2019

The major problem encountered during the storage of pig slurry (PS) is the release of huge amounts of greenhouse gases (GHGs), which are dominated by methane ($CH_4$). To reduce this, concentrated sulfuric acid has been used as an additive to control the pH of pig slurry to 5.0-6.0. However, other low-risk substitutes have been developed due to some limitations to its use, such as corrosiveness, and hazards to animal and human health. In this study, sugar addition was proposed as an eco-friendly approach for limiting $CH_4$ emission from PS during storage. The pH of PS has been reduced from $7.1{\pm}0.1$ (control) to $5.8{\pm}0.1$, $4.6{\pm}0.1$, $4.4{\pm}0.1$, $4.1{\pm}0.1$, and $4.0{\pm}0.1$, by the addition of 10, 20, 30, 40, and 50 g sugar/L, respectively. Lactate, acetate, and propionate were detected as the dominant organic acids and at sugar concentration above 20 g/L, lactate concentration represented 42-72% (COD basis) of total organic acids. For 40 d of storage, $20.6{\pm}2.3kg\;CO_2\;eq./ton\;PS$ was emitted in the control. Such emission, however, was found to be reduced to $8.7{\pm}0.4$ and $0.4{\pm}0.1kg\;CO_2\;eq./ton\;PS$ at 10 and 20 g/L, respectively. Small amount of $CH_4$ from PS at 10 g/L was emitted until 30 d of storage, while for rest of storage period, it has increased to $8.7{\pm}0.4kg\;CO_2\;eq./ton\;PS$ ( 40% of the control) when methanogens have recovered by increasing pH to 7.0. By the end of storage, VS and COD removal in the control reached 24% and 27%, while their ranges reached 15-4% and 12-17% in the sugar added experiments, respectively. It was found that more than 90% of COD removal was done by aerobic biological process.

• Proceedings of the Korean Society of Crop Science Conference
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• 2019.09a
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• pp.5-5
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• 2019

The objectives of this paper are (i) to analyze past trends and future directions of rice production, consumption and trade across the world and (ii) to discuss emerging challenges and future directions in the global rice industry. Rice is a staple food of over half of the world's 7.7 billion people. It is an important economic, social, political, and cultural commodity in most Asian countries. Rice is the $1^{st}$ most widely consumed, $2^{nd}$ largely produced, and $3^{rd}$ most widely grown food crop in the world. It was cultivated by 144 million farms in over 100 countries with harvested area of over 163 million ha producing about 745 million tons paddy in 2018. About 90% of the total rice is produced in Asia. China and India, the biggest rice producers, account for over half of the world's rice production. Between 1960 and 2018, world rice production increased over threefold from 221 to 745 million tons (2.1% per year) due to area expansion from 120 to 163 million ha (0.5% per year) and paddy yield increase from 1.8 to 4.6 t/ha (1.6% per year). The Green Revolution led massive increase in rice production prevented famines, provided food for millions of people, reduced poverty and hunger, and improved livelihoods of millions of Asians. The future increase in rice production must come from yield increase as the scope for area expansion is limited. Rice is the most widely consumed food crop. The world's average per capita milled rice consumption is 64 kilograms providing 19% of daily calories. Asia accounted for 84% of global consumption followed by Africa (7%), South America (3%), and the Middle East (2%). Asia's per capita rice consumption is 100 kilograms per year providing 28% of daily calories. The global and Asian per capita consumption increased from the 1960s to the 1990s but stable afterward. The per capita rice consumption is expected to decline in Asia but increase outside Asia especially in Africa in the future. The total milled rice consumption was about 490 million tons in 2018 and projected to reach 550 million tons by 2030 and 590 million tons by 2040. Rice is thinly traded in international market because it is a highly protected commodity. Only about 9% of the total production is traded in global rice market. However, the volume of global rice trade has increased over six-fold from 7.5 to 46.5 million tons between the 1960s and 2018. A relatively small number of exporting countries interact with a large number of importing countries. The top five rice exporting countries are India, Thailand, Vietnam, Pakistan, and China accounting for 74% of the global rice export. The top five rice importing countries are China, Philippines, Nigeria, European Union and Saudi Arabia accounting for 26% of the global rice import. Within rice varieties, Japonica rice accounts for the highest share of the global rice trade (about 12%) followed by Basmati rice (about 10%). The high concentration of exports to a few countries makes international rice market vulnerable to supply disruptions in exporting countries, leading to higher world prices of rice. The export price of Thai 5% broken rice increased from 198 US$/ton in 2000 to 421 US$/ton in 2018. The volumes of trade and rice prices in the global market are expected to increase in the future. The major future challenges of the rice industry are increasing demand due to population growth, rising demand in Africa, economic growth and diet diversification, competition for natural resources (land and water), labor scarcity, climate change and natural hazards, poverty and inequality, hunger and malnutrition, urbanization, low income in rice farming, yield saturation, aging of farmers, feminization of agriculture, health and environmental concerns, improving value chains, and shifting donor priorities away from agriculture. At the same time, new opportunities are available due to access to new technologies, increased investment by the private sector, and increased global partnership. More investment in rice research and development is needed to develop and disseminate innovative technologies and practices to overcome problems and ensure food and nutrition security of the future population.