This study measured and analyzed the heavy metal (Cd, As) content of fine dust in the city of Gwangyang, Jeonnam from September 19 to September 22, 2016. For cadmium, the arithmetic average was 0.21 ng/m3 (0.12~0.49 ng/ m3), which did not exceed the WHO's recommended level. The average of arsenic was 2.41 ng/m3 (0.30~142.08 ng/ m3) and the geometric mean was 11.18 ng/m3, which exceeded the WHO's recommended standard in 16 out of 24 measurements. In the case of cadmium, the CTE of male was 9.22 × 10−8 RME 1.91 × 10−7 and the female CTE was 9.44 × 10−8 RME 1.92 × 10−7, which did not exceed the EPA limit of CTE 2.18 × 10−5 RME 1.51 × 10−4 for men and CTE 2.23 × 10−5 RME 1.51 × 10−4 For women, CTE 2.23 × 10−5 RME 1.51 × 10−4 results were obtained, which exceeded the EPA's recommended limit and also exceeded the maximum allowable limit of 10-4.

The objective of this study was to assess RF-EMF exposure levels in indoor daycare centers in a Metropolitan city. RF-EMF measurements were collected and surveyed from 50 volunteer daycare centers in the Korea between October 2013 and October 2014. Through our research, it was found that the main exposure source for indoor daycare centers is the frequency bands for TV and Radio broadcasting (FM: 88.1~107.9 MHz), mobile phone (869~894 MHz, 1840~1870 MHz, 1885~2170 MHz), wireless LAN and home electronics, etc., including TRS, Wireless Data Communication. The RF-EMF exposure levels for all daycare centers were far below the recommended standards of EMF Guideline Korea and international reference levels proposed by ICNIRP (International Commission on Non-Ionizing Radiation Protection). However, in terms of long term health effects some uncertainty exists, and thus minimizing exposure may reduce this uncertainty. The data we collected will be useful data for determining RF-EMF management and risk communication at daycare centers.

The objective of this study is to safety assessment for human body on the guided missile combustion products. This study is to verify the safety assessment when operating the interior missile ejection take on verify the safety of the human body. During the missile ejection of combustion products, this study is analyzed combustion products. Result are accepted NIOSH and KOSHA of the safe guideline, and 6 exposure gas to the specified values 42% (CO), 22% (CO2), not detected (others) are within minimal exposures criteria of the reference value respectively. Contribution of these results supported that interior missile ejection during combustion products may have been ensured human safely. Therefore, the future for improving the environmental safety of the shooting projectile steel plate round, dust collector, ventilation and other facilities is to improve environmental safety and efficient renovated design needed by target focused areas.

This study was conducted to compare the value of the working environment measurement with the expected exposure value drawn by using a program, thereby going to investigate whether it is available to the risk assessment of domestic workplace. We used the ECETOC TRA program which is one of the exposure predictive models. Four kinds of substances were measured in two workplace which was exposed to organic solvents and one kind of substance was measured in three workplace which was exposed to dusts and then an exposure assessment of chemical risk factors was conducted. The result value of the working environment measurement, solid substance exceeded standard in one site, and it was found that the other solid and liquid substances were within the standard. The value of the exposure assessment program showd the same result; it was higher than the value of the working environment measurement, suggesting that due to its nature, the exposure assessment program is run only on the worst situation. Therefore, it was found that when the exposure assesment program is used, variables should be substituted only after accurately assessing the workplace and it is a good idea to assess the risk beforehand with the exposure assessment program in the case of the workplace which employs no more than 5 people and where it is hard to assess the working environment.

The objective of the present study was to estimate the health risk level for children exposed to phthalate and identify the pathways including indoor floor dust, surface wipe and hand wipe in elementary-schools and institutes. The samples of indoor place were collected at children's facilities (50 elementary-schools and 46 academies) in summer (Aug ~ Sept, 2008), winter (Dec 2008 ~ Feb, 2009) and Spring (Mar ~ Apr, 2009) periods. Hazard Index (HI) were estimated for the non-carcinogens and the examined phthalate were diethylhexyl phthalate (DEHP), dibutyl-n-butyl phthalate (DnBP), butylbenzyl phthalate (BBzP). Risk analysis indicates that did not exceed 0.01 (HI) for all subjects in all facilities it's 50^th % and 95^th % value. For DEHP, DnBP and BBzP their detection rates through multi-pathways were high and their risk based on health risk assessment was also observed to be acceptable.

Information on time spent in microenvironments has a critical role in individuals’ exposure assessment. Time-activity studies have become an integral part of comprehensive exposure assessment and personal exposure modeling. The aims of this study were to estimate the exposure level of NO₂, PM₁₀ and VOCs, and to compare the estimated exposure by using time-activity pattern and indoor air concentration. This study was performed upon 28 university students living in Daegu. We measured air pollutants of NO₂, PM₁₀ and VOCs at houses where the university students spent most their times. In this study, according to the summer and winter, time-activity patterns of university students were different. The 28 university students average spending times in house indoors and other indoors time were 11.52±2.14 and 7.63±2.65 hours in summer, and 14.78±3.30 and 6.59±3.03 hours in winter, respectively. The university students personal exposure NO₂ concentrations were average 21.62±5.88 ppb and I/O ratio was 0.89±0.27. Personal average exposure of PM₁₀ concentration was between house indoors and outdoors concentrations which indoor house concentration was 37.68±7.57 μg/m³ and outdoor house concentration was 43.85±9.80 μg/m³ with 0.88±0.17 of I/O ratio. Personal exposure to benzene and the average concentration of benzene did not exceed in atmosphere environmental standard (annual 1.5 ppb) and the outdoor houses concentration was much higher than indoor houses.

The aim of this study was to calculate the health risks which children were exposed to trace metals through several pathways including air, floor dust, wipe and hand wipes in elementary-schools and academies. The samples were collected at children's facilities (50 elementary-schools and 46 academies) in summer (Aug ~ Sept, 2008), winter (Dec 2008 ~ Feb, 2009) and Spring (Mar ~ Apr, 2009) periods. The lifetime Excess Cancer Risks (ECRs) were estimated for carcinogen trace elements such as As, Cd, and Cr. For carcinogens, the Excess Cancer Risk (ECR) was calculated by considering the process of deciding Cancer Potency Factor (CPF) and Age Dependent Adjust Factor (ADAF) of the data of adults. Hazard Quotients (HQs) were estimated for the non-carcinogens trace metals like Cd, Cr, Hg and Pb. The average ECRs for young children were 1×10^-9~1×10^-8 (50%th percentile) level in all facilities. Non-carcinogens did not exceed 0.1 for all subjects in all facilities. For trace metals their risk based on health risk assessment was also observed to be acceptable.

The purpose of this study was to investigate the health risk and management of childhood exposure to indoor aldehydes in elementary-schools and academies. The samples were collected at children's facilities (50 elementary-schools and 46 academies) in summer (Aug ~ Sept, 2008), winter (Dec 2008 ~ Feb, 2009) and Spring (Mar ~ Apr, 2009) periods. The overall mean concentration of formaldehyde was 68.3 ㎍ /m³ and 27.2% of exceeded the 100 ㎍/m³ by the school health guideline. The concentration ratio of Indoor air and outdoor air (I/O) of aldehydes exceeds 1.0. The level of indoor air contamination did appear to be high, and 24.6% of the academies evaluated had exceeded the formaldehyde level specified by the public health act (120㎍ /m³). We estimated the lifetime excess cancer risks (ECRs) of formaldehyde, and the hazard quotients (HQs) of non-carcinogens (acetaldehyde and benzaldehyde). In addition, for carcinogens, the excess cancer risk (ECR) was calculated by considering the process of deciding cancer potency factor (CPF) and age dependent adjust Factor (ADAF) of the data of adults. The average ECRs of formaldehyde for young children were 1×10^-6~1×10^-5 level in all facilities. HQs of formaldehyde did exceed 0.1 for all subjects in elementary school.

This survey was conducted to develop an appropriate management for safety of children snacks. In this study, monitorings of food additives such as nine kinds of tar colors (tartrazine, sunset yellow FCF, brilliant blue FCF, indigo carmine, new coccine, amaranth, erythrosine, allura red and fast green FCF) which are sold at stationary store around the school, were performed. Eighty two samples (3 snacks, 71 candies, 4 chocolates and 4 beverages)were analyzed for tar colors. Results of risk assessment for tar colors were expressed as EDI (Estimated Daily Intake) comparing with ADI (Acceptable Daily Intake). The ratio of high risk group for tar color intake (95th) were 0-3.56%. The consumptions of tar colors from domestic and imported products for nine kinds of tar colors in candies were not significantly different. The results of this study indicated that each EDI of nine kinds of tar colors sold at stationary store around the school is much lower than each ADI in general. Consequently, the children snacks are thought to be safe for consumption.

This study assessed the health risk of trace elements in indoor children-facilities by multi-pathway measurements (Air, Dust, Wipe, Hand washing). The samples of indoor place were collected at various children's facilities (40 day-care houses, 42 child-care centers, 44 kindergartens, and 42 indoor playgrounds) in summer (Jul~Sep, 2007) and winter (Jan~Feb, 2008) periods, and analyzed by ICP-MS. The lifetime Excess Cancer Risks (ECRs) were estimated for carcinogen trace elements such as As, Cd, Cr and Ni. For carcinogens, the Excess Cancer Risk (ECR) was calculated by considering the process of deciding Cancer Potency Factor (CPF) and Age Dependent Adjust Factor (ADAF) of the data of adults. Both Hazard Quotients (HQs) and Hazard Index (HI) were estimated for the non-carcinogens and children sensitivity trace elements like Cd, Cu, and Cr. The average ECRs for young children were 1×10^-10~1×10^-6 (50%th percentile) level in all facilities. Non-carcinogens and Children's sensitivity materials did not exceed 1.0 (HQs, HI) for all subjects in all facilities. For trace elements their detection rates through multi-pathways were not high and their risk based on health risk assessment was also observed to be acceptable. In addition, through education on the risk of multi-pathway exposure of trace elements for managers of facilities as well as for users the risk control of exposure of children.

Domestic studies for identification of causality between children exposure to toxic chemicals, such as arsenic (As) and resulted hazardous effects were not implemented. This study was conducted to probabilistically estimate dietary As intake and health risk assessment for young children and all age-specific populations from the consumption of As-contaminated rice of Korea. Arsenic intakes for young children (1 to 6 years old) from As-contaminated rice were higher than other age-specific groups, based on a dose-per-body weight basis. Based on the current EPA cancer slope factor for As, estimated cancer risks (to the skin cancer) associated with dietary intake of As-contaminated rice for 1 to 2 years old group and 3 to years old group are 1.76 per 10,000 and 3.16 per 10,000, respectively, at the 50th percentile. Based on possible reference levels (0.005 mg/kg/day) for children, mean and 95th percentile value of HQ from rice for young children are very below 1.0, which is a regulatory limit of non-carcinogenic risks for human.

The purpose of this study is to investigate the potential exposure of chemicals from the working environment of nail shops and determine health-related symptoms from the nail shop workers by self-reporting questionnaire. A total of 54 nail shop workers from 15 different locations were asked to conduct a survey concerning their working environment. VOCs (including toluene and nine other substances) and aldehyde(including formaldehyde and four other substances) detected. We studied on the relationship between the environmental concentration of chemical substances and the self-reported symptoms of nail shop workers. There was a significant relationship between the neck pain and substances such as 2- propanol, benzene, toluene, n-buthylacetate, ethylbenzene, and xylene (p<0.01). Furthermore, symptoms in the nose irritation, neck irritation and recurrent coughs had significant relationship with benzene (p<0.05), whereas, toluene showed significant relationship with neck irritation and symptoms such as coughs and fatigue (p<0.05).

This study was performed to investigate the concentration of indoor aldehydes in children’s facilities. The samples were collected from various children's facilities (40 playrooms, 42 day-care centers, 44 kindergartens, and 42 indoor playgrounds) in summer (Jul~Sep, 2007), winter (Jan~Feb, 2008) and spring (Mar~Apr, 2008). The ratio of Indoor and outdoor (I/O) of aldehydes exceeds 1.0 and the formaldehyde levels in each child-care facilities were significantly different. We evaluated the lifetime cancer and non-cancer risk of young children due to indoor aldehyde exposure. We estimated the lifetime excess cancer risks (ECRs) of formaldehyde, acetaldehyde and the hazard quotients (HQs) of non-carcinogens (benzaldehyde and formaldehyde). Formaldehyde was evaluated for both carcinogenic and non-carcinogenic risk. The average ECRs of formaldehyde for young children were 1×10^-4~1×10^-5 level in all facilities. HQs of four non-carcinogens did not exceed 1.0 for all subjects in all facilities.

The aim of this study was to determine exposure assessment of pathogenic bacteria in edible ices by using the monitoring data from the previous study. According to the results of exposure assessment of edible ices contaminated with S. aureus, the contamination level of S. aureus in raw materials was higher than other foodborne pathogens, and the contamination level of S. aureus in mixed samples increased much before sterilization. The most significant reduction in contamination level was observed in mixed samples after sterilization, thus, the contamination levels in frozen final products was less than that of raw materials. Overall, the possibility for the infection of foodborne bacteria from the intake of edible ices per person per day was ranged from minimum 5.89 × 10-7 to maximum 5.01 × 10-5. For more realistic estimates, consumption of edible ices and dose-response model must be studied further.

This study performed and re-analysed the articles of exposure assessment for the indoor environment of houses in many environment-related journals published. in Korea since 1990. Based on this comparative study, we estimated the unit health risk on indoor environment. The objective of this study was to offer scientific data for decision-making policy for improvement and management of indoor air quality on Korean house in. The pooled concentrations for the critical air pollutants in the house were 13.93±13.91㎍/m3 (PM10), 680±226 ppm for (CO2), 1.9±1.6 ppm (CO), 419±158 CFU/m3 (bacteria), 0.036 ± 0.002 ppm (NO2), and 104.935 ± 16.424 Bq/m3 (Rn), The pooled concentrations for the volatile organic compounds were 6.9±6.7㎍ /m3 (benzene), 39.3±55.1㎍/m3 (toluene), 4.2±4.0㎍/m3 (ethylbenzene), 11.4±8.3㎍/m3 (m, p-xylene), 4.2 ±1.5㎍/m3 (styrene) and 6.3±4.5㎍/m3 (o-xylene). The unit cancer risk for men and women by inhalation of benzene was 3.7 × 10-5 and 4.8 × 10-6, respectively. In additio

Indoor air quality tends to be the dominant contributor to personal exposure, because most people spend over 80% of their time indoors. In this study, indoor and outdoor NO2 concentrations were measured simultaneously with personal exposures of 30 university students in weekday and weekend in Daegu, Korea. House characteristics and subject's activity pattern were used to determine the effects on personal exposure. Since university students spent most of their times indoor, their NO2 exposure was associated with indoor NO2 level during both weekday and weekend in spite of different time activity. Using a time-weighted average model, NO2 exposures of university students were estimated by NO2 measurements in indoor home, indoor school, and outdoor home. In conclusion, major personal exposure to NO2 resulted from air quality of indoor environment at house.

PAHs 화합물은 유기탄소화합물의 불완전연소에 의해 주로 발생하는데, 일반인들은 대기오염에 의한 호흡노출과 가열조리식품의 경구섭취가 주요 인체노출경로로 알려지고 있다. 본 연구에서는 PAHs화합물에 오염된 식품이 식생활에 많은 부분을 차지하고 있어 우리나라 대표식품을 참고로 가정식과 외식의 식단을 작성하고 작성한 식단을 근거로 식품 중 PAHs화합물 오염도를 분석하여, 분석된 PAHs화합물의 오염도 자료를 활용한 가정식과 외식 1끼 식사를 기준으로 인체노출량을 비교하고, 성인 하루 가정식 2회, 외식 1회 섭취시의 1일인체노출량을 평가하였다. 다빈도·다소비식품에서 PAHs화합물 오염도를 분석한 결과 총 PAHs농도는 2.00~141.28 ug/kg의 범위로 검출되었으며, 멸치볶음이 가장 높게 나타났다. 상대독성계수(TEFs)를 활용하여 환산한 독성등가량은 0.03~l.31 ugTEQ_(BaP)/kg 범위였고, 가장 높은 값을 가진 식품은 햄버거이었다. 식품별 오염도와 노출변수들을 고려하여 산출한 끼니별 가정식과 외식에서의 PAHs 화합물 평균인체노출량은 각각 2.4×10^(-3) ugTEQ_(BaP)/kg/meal와 4.0x10^(-3) ugTEQ_(BaP)/kg/meal으로 외식이 가정식보다 PAHs화합물의 인체노출이 1.7배가 높은 수준으로 나타났다. 햄버거, 숯불쇠고기구이, 숯불삼겹살구이, 고등어구이 등은 PAHs화합물 오염도와 독성등가량 및 1회분식품섭취량이 모두 높아 PAHs화합물의 주요노출기여 식품인 것을 알 수 있었다. 가정식에서 미역국이 1.8x10^(-3) ugTEQ_(BaP)/kg/meal으로, 외식에서는 햄버거가3.9x10^(-3)ugTEQ_(BaP)/kg/meal으로 기여도가 가장 높았다 하루 3회 식사를 고려한 1일 PAHs화합물인체노출량수준은 8.0x10^(-3)~9.7×10^(-3) ug/kg/day 이었다. 본 연구 결과가 PAHs 화합물의 안전성평가와 기준규격설정의 필요성 및 식품안전관리를 위한 규제를 제정하는 기초 자료가 되길 바라며, PAHs화합물의 고노출상황을 줄일 수 있는 개개인의 계획된 식단 작성시, 이에 대한 정보를 제공하고자 한다.

Daily exposure of aflatoxin B₁ (AFB₁) was estimated in foods (rice, barley, soybean, peanut, soysauce, soybean paste) by ELISA (enzyme linked immunosorbent assay) using polyclonal antibody R_(101). Before ELISA, a simple extraction method was applied for the quantitation of AFB₁ in foods using chloroform which showed high recovery (70± 12%). AFB₁ levels in foods were 0.32 ng/ml (rice), 0.24 ng/ml (barley), 0.22 ng/ml (peanut), 0.30-0.78 ng/ml (soysauce), and 0.2 ng/ml (soybean paste). Based on food consumption, we estimated that Koreans were exposed to AFB₁ at the level of 1.86±0.46 ng/kg/day and liver cancer incidence attributed to AFB₁ exposure (assuming that AFB₁ as a single hepatocarcinogenic agent) might be calculated to be 13.1 per 100,000 population. Our data demonstrate that AFB₁ levels in foods were below the regulation of 10 ppb in foods and might not be the major risk factor for the high incidence of liver cancer in Korea.

The primary purpose of this study was to determine the risk of various disease outcomes due to exposure to cyanobacteria toxin (microcystin-LR) through drinking water in a Korean watershed. In order to determine the risk in a more quantitative way, the risk assessment framework developed by the National Research Council (NRC) of the United States (US) - hazard identification, dose-response relationship, exposure assessment, and risk characterization - was used in this study. For dose-response relationships, a computer software (BenchMark Dose Software (BMDS)) developed by the US Environmental Protection Agency (EPA) was used to fit the data from previous studies showing the relationship between the concentration of microcystin-LR and various disease outcomes into various dose-response models. For exposure assessment, the concentrations of microcystin-LR in the source water and finished water in a Korean watershed obtained from a recent study conducted by the Ministry of Environment of Korea were used. Finally, the risk of various disease outcomes due to exposure to cyanobacteria toxin (microcystin-LR) through drinking water was characterized by Monte-Carlo simulation using Crystall Ball program (Oracle Inc.) for adults and children. The results of this study suggest that the risk of disease due to microcystin-LR toxin through drinking water is very low and it appears that current water treatment practice should be able to protect the public from the harmful effects of cyanobacteria toxin (microcystin-LR) through drinking water.