This study was to assess the lifetime cancer and non-cancer risk on exposure to volatile organic compounds (VOCs) and formaldehyde of worker and user at public facilities in Korea. We measured the concentrations of formaldehyde and VOCs in indoor air at 160 public buildings that 5 kinds of public facilities (30 hotel, 30 fitness center, 25 gosiwon, 30 reading-room and 45 video-room) all over the country. There were estimated the human exposure dose and risks with averages of the using-time and frequency for facility users and office workers, respectively. Carcinogens (benzene and formaldehyde) were estimated the lifetime excess cancer risks (ECRs). Non-carcinogens (toluene, ethylbenzene, xylene, and styrene) were estimated the hazard quotients (HQs). HQs of four non-carcinogens did not exceed 1.0 for all subjects in all facilities. Higher HQs of toluene were observed at the reading-room. The average ECRs of formaldehyde and benzene for facility worker and user were 1×10-4~1×10-6 level in all facilities. The estimated ECRs for reading-room were the highest and the fitness center and gosiwon were the next higher facilities. Because lifetime ECRs of carcinogens exceeded 1×10-4 for facility worker in the most facilities, risk management of formaldehyde and benzene in the facilities was necessary. IAQ guidelines should be determined strictly to prevent occurrence of disease caused by poor IAQ beforehand.
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).
In this study, we attempted to estimate the association between asthma oriented by indoor air sources and personal exposure by comparing the case (asthma-patient) and control (non-asthma-patient) groups. We selected 27 participants who showed positive response on lung function and methacholin provocation test. We performed environmental survey with 15 and 10 cases during May and June 2007, respectively. There was no significant difference between the case and control groups in the level of formaldehyde and TBC (Total Bacterial Count). In the dust allergen test, the case concentration was higher than the control's, without signifiant difference. In the personal exposure assessment of VOCs using OVM (Organic Vapor Monitor) badge, the case concentrations of Benzene, Toluene, and Ethylbenzene were higher than the control's, but there was no significant difference. The personal exposure of Xylene case study was significantly higher than the control's
This study was carried out to assess the improvement of treatment by the house-plant. For the purpose of this study, 17 asthma-patients residing in Seoul were selected as participants during January to March 2007. We measured VOCs and conducted clinical survey during April to September 2007. In this study, 6 species of houseplants known to be eco-friendly were investigated for the health effect along with 12 other plants. The research focused on peak expiratory flow rate(PEFR) and disease specific quality of life. When the results were compared to the non-intervention households, the intervention households had reduced levels of acetaldehyde, benzene, ethylbenzene, xylene and styrene. The reduction rate estimated from this comparative study was statistically significant(p<0.05). There was however no association between the intervention and the estimated PEFR between morning and evening data in asthma-patients.
This study was to assess the health risk of VOCs in indoor air under uncontrolled Korean-IAQ regulation. We measured the concentrations of formaldehyde and 5 VOCs (benzene, toluene, ethylbenzene, xylene, and styrene) in indoor air at 232 public buildings for four kinds of public facility (32 wedding halls, 17 Gymnasiums, 20 Galleries, and 166 Welfare facilities) around the country. There were estimated the human exposure dose and health risk used average time and frequencies of questionaries for subjects such as facility users and office workers. There were estimated the lifetime excess cancer risk (ECR) for carcinogens (formaldehyde and benzene) and hazard quotient (HQ) for non-carcinogens (toluene, ethylbenzene, xylene and styrene). For the facility user, the average levels of ECRs were 10-4∼10-5 and 10-5 ∼10-6, respectively, for formaldehyde and benzene in all facilities. HQs of four non-carcinogens were not exceeded 1.0 in all facilities and subjects. In addition, there was showed the highest ECR in the smoking facility.
The objective of the present study was to assess the health effect of houseplant. we selected 22 households of newly-built apartments and 17 asthma patients. Before intervention in the households, we conducted clinical survey investigations during April and October, 2006. In this study, 6 species of houseplants known to be eco-friendly and 14 other plants were recruited. While the clinical research items were lung function, erythrocyte sedimentation rate(ESR), white blood cell count(WBC), total eosinophil count(TEC) and total-immunoglobulin E(T-IgE). There was no association between the intervention and the estimated inflammation reaction and allergic reaction. However, peak expiratory flow rate(PEFR) of evening data were positive effect in the intervention asthma-patients households compared with the nonintervention.
본 연구에서는 식품산업에 적용 가능한 amylase의 발굴을 위하여 된장으로부터 amylase를 생산하는 균주를 분리하였고, 분리된 미생물들의 동정을 통하여 GRAS 미생물로 부터 생산되는 amylase에 대한 효소 특성을 규명하였다. 그 결과 균주 유래 16S ribosomal RNA 유전자 염기서열에서B. subtilis로 동정되어 본 균주를B. subtilis CBD2로 명명하였다. B. subtilis CBD2 균주의 생육에 미치는 배지 성분에 대한 특성을 검토한 결과 본 균주는 pH 7.0, NaCl 3%, glucose 10%에서 가장 높은 균 생육 특성을 나타내었다. 그리고 본 균주의 amylase 생산에 미치는 탄소원의 영향을 검토한 결과, 본 균주는 soluble starch, corn starch, maize amylopectin 및 wheat starch 중에서 soluble starch를 탄소원으로 사용하였을 때 가장 높은 amylase 생산성을 나타내었다. B. subtilis CBD2유래 amylase의 활성에 미치는 반응 조건을 검토한 결과 본 균주 유래 amylase는 pH 8.0 그리고 50°C에서 가장 높은 효소 활성을 나타내었으며 기질특이성에 대한 검토에서는 corn starch>wheat starch>soluble starch>maize amylopectin 순으로 효소 활성을 나타내었다. B. subtilis CBD2가 생성하는 amylase 효소와 corn starch 기질 반응에 대한 전분 분해능 및 당 생성율 변화에서는 24시간에서 가장 높은 전분 분해능 및 당 생성율을 나타내어 corn starch를 이용한 효소 반응은 24시간이 가장 적절함을 확인할 수 있었다. 따라서 본 연구에서 분리된 균주는 GRAS 미생물인B. subtilis이었으며 본 균주 유래의 amylase 특성을 활용한다면 향 후 식품산업에 있어서 전분 분해 관련 분야에 유용하게 이용될 것으로 기대되어진다.