Bioaerosol exposure by farm type in Korea.

INTRODUCTION AND OBJECTIVE: Bioaerosols exist in almost every environment and are known to be risk factors for a variety of diseases. Agricultural work involves high exposure to bioaerosols and its workplace concentrations affect the surrounding areas. The study evaluates bioaerosol concentrations in agricultural workplaces and residential areas according to farm type. MATERIAL AND METHODS: In 2013-2015, a total of 381 samples were collected for endotoxin and microbial testing from three farm types: open field, greenhouse, and livestock facilities. Endotoxins were measured using a 37-mm glass fire filter connected to an air pump calibrated to 2 LPM. Microorganisms were measured using a gelatin filter and impaction (single-stage Andersen sampler). RESULTS: The concentration of endotoxins and microorganisms at the livestock facilities was significantly higher than in the open fields and greenhouses (p<0.05). Among the livestock farms, the concentrations of endotoxins and gram-negative bacteria were highest at hog farms, and the concentrations of total bacteria and fungi were the highest in poultry houses. In both greenhouses and livestock facilities, the concentrations of bioaerosols were higher in the workplace than in a nearby residential area, and the difference in concentration was significantly greater in the case of livestock facilities. CONCLUSIONS: The concentrations of bioaerosols in agricultural workplaces and nearby residential areas were higher than in the control and general areas. Therefore, measures should be taken to prevent exposure to bioaerosols at agricultural workplaces and their vicinities.

Cesium-137 Contaminated Roads and Health Problems in Residents: an Epidemiological Investigation in Seoul, 2011.

BACKGROUND: In 2011, two roads in a residential area in Seoul were found to be contaminated with the radionuclide cesium-137 (137Cs). In response to public concerns, an epidemiological study was conducted. METHODS: The standardized cancer incidence ratios in the affected and neighboring regions were calculated based on the central cancer registry. Households in the region were sampled using the random stratified sampling technique, and questionnaires were administered to family members, via home visit and via students in elementary to high schools. Information on duration of residency and frequency of use of the roads was applied to calculate cumulative radiation exposure dose from the roads, alongside with the reported 137Cs contamination amounts. Information on past medical history, perceived risk, anxiety and psychological stress was also obtained. Of the 31,053 residents, 8,875 were analyzed. To examine possible associations between radiation exposure and health problems, logistic regression adjusted for covariates were performed with consideration of the sampling design, population weight and stratification. RESULTS: No significant association was found between self-informed diseases, including cancers, and estimated radiation exposure dose. According to an increase of radiation level, a significant increase in anxiety in all and a decline in the psychosocial wellbeing of the adults was noted. The risk perception level was higher in the elderly, females, the less educated, and the highest exposed individuals. CONCLUSION: This study provides a basis for risk communication with residents and community environmental health policy.

Level of radiation dose in university hospital noninsured private health screening programs in Korea.

OBJECTIVES: The aim of this study is to evaluate radiation exposure resulting from the comprehensive health examinations of selected university hospital programs and to present basic data for research and management strategies on the health effects of medical radiation exposure. METHODS: Radiation-based diagnostic studies of the comprehensive health examination programs of ten university hospitals in Seoul, Korea, as introduced in their websites, were analyzed. The medical radiation studies of the programs were reviewed by radiologists. Only the effective doses of the basic studies were included in the analysis. The optional studies of the programs were excluded. RESULTS: Among the 190 comprehensive health examination programs, 132 programs (69.5%) included computed tomography studies, with an average of 1.4 scans. The average effective dose of radiation by program was 3.62 mSv for an intensive program for specific diseases; 11.12 mSv for an intensive program for cancer; 18.14 mSv for a premium program; and 24.08 mSv for an overnight program. A higher cost of a programs was linked to a higher effective dose (r=0.812). The effective doses of the examination programs for the same purposes differed by as much as 2.1 times by hospital. Inclusion of positron emission tomography-computed tomography was the most critical factor in determining the level of effective dose. CONCLUSIONS: It was found that radiation exposure dose from comprehensive health exam programs targeted for an asymptomatic, healthy public reached between 3.6 and 24 times the annual dose limit for the general public. Relevant management policies at the national level should be provided to minimize medical radiation exposure.

Assessment of radiation exposure from cesium-137 contaminated roads for epidemiological studies in Seoul, Korea.

OBJECTIVES: We aimed to assess the radiation exposure for epidemiologic investigation in residents exposed to radiation from roads that were accidentally found to be contaminated with radioactive cesium-137 ((137)Cs) in Seoul. METHODS: Using information regarding the frequency and duration of passing via the (137)Cs contaminated roads or residing/working near the roads from the questionnaires that were obtained from 8875 residents and the measured radiation doses reported by the Nuclear Safety and Security Commission, we calculated the total cumulative dose of radiation exposure for each person. RESULTS: Sixty-three percent of the residents who responded to the questionnaire were considered as ever-exposed and 1% of them had a total cumulative dose of more than 10 mSv. The mean (minimum, maximum) duration of radiation exposure was 4.75 years (0.08, 11.98) and the geometric mean (minimum, maximum) of the total cumulative dose was 0.049 mSv (<0.001, 35.35) in the exposed. CONCLUSIONS: An individual exposure assessment was performed for an epidemiological study to estimate the health risk among residents living in the vicinity of (137)Cs contaminated roads. The average exposure dose in the exposed people was less than 5% of the current guideline.

Characterization of the monthly variation in (1 → 3)-ß-D-glucan concentrations in university laboratories.

We characterize the monthly variation in (1 → 3)-ß-D-glucan concentration measured over the course of 1 year, and we evaluate the characteristics of size selection using a two-stage cyclone sampler. The (1 → 3)-ß-D-glucan concentrations were measured in four bio-related laboratories. A total of 156 samples were collected using a new two-stage cyclone sampler. Analysis of (1 → 3)-ß-D-glucan was performed using the kinetic Limulus amebocyte lysate assay. The study showed that airborne (1 → 3)-ß-D-glucan concentrations were significantly higher in laboratory D (mean ± SD 1,105 ± 1,893 pg/m(3)) and in the spring (5,458 pg/m(3)). The highest concentration of (1 → 3)-ß-D-glucan occurred in the spring, particularly in May.

Paraquat application and respiratory health effects among South Korean farmers.

OBJECTIVES: Paraquat is commonly used worldwide as major herbicide. The objective of this study was to investigate the association among farmers between occupational paraquat exposure and respiratory health effects. METHODS: A cross-sectional survey of health effects related to an oil spill was conducted in South Korea from 2008 to 2009. For this analysis, a total of 2882 full-time farmers were selected from the overall sample. Data collection included an interviewer-administered questionnaire and spirometry testing. Logistic regression analysis and linear regression analysis were performed to evaluate the relationship between paraquat exposure and respiratory health outcomes after adjustment for potential confounders. RESULTS: The risks of self-reported physician-diagnosed asthma, chronic obstructive pulmonary disease and allergic rhinitis were non-significantly increased among paraquat-applying farmers compared with non-paraquat-applying farmers. Although the results of a pulmonary function test fell within normal limits, a decline in forced vital capacity and forced expiratory volume in one second was apparent among paraquat-applying farmers compared with non-paraquat-applying farmers. Forced vital capacity (ß = -5.20, p<0.001) and forced expiratory volume in one second (ß = -1.89, p = 0.010) significantly decreased with each unit increase in years of paraquat application. Paraquat-applying farmers showed a significant exposure-response relationship between restrictive ventilatory defects and paraquat application years (p trend = 0.015) or lifetime days of application (p trend = 0.007). CONCLUSIONS: Our findings suggest a possible association between paraquat application and adverse respiratory health effects among farmers.

The "Chair Campaign" in Korea: an alternative approach in occupational health and safety for service workers.

In spite of the increasing number of service workers in Korea, their occupational health and safety concerns have largely been neglected. It is in this context that the Chair Campaign, which lasted four months, was launched as an alternative occupational health approach for service workers. The campaign succeeded in getting wide public support, bringing about a special inspection by the Ministry of Labor. Finally, chairs were provided for workers at checkout counters in 71 department stores and 449 large discount stores. However, there are still many workplaces where workers cannot sit, whether chairs are provided or not. Although there is still much to be done, this campaign raised social awareness that service workers, mainly women, have the right to work in healthy and safe conditions. This paper will review the campaign and evaluate its achievements and limitations.

[Reliability of self-reported information by farmers on pesticide use].

OBJECTIVES: Exposure assessment is a major challenge faced by studies that evaluate the association between pesticide exposure and adverse health outcomes. The objective of this study was to investigate the reliability of information that farmers self-report regarding their pesticide use. METHODS: Twenty five items based upon existing questionnaires were designed to focus on pesticide exposure. In 2009 a self-administrated survey was conducted on two occasions four weeks apart among 205 farmers residing in Gyeonggi and Gangwon provinces. For a reliability measure, we calculated the percentage agreement, the kappa statistics and the intraclass correlation coefficient (ICC) between the two reports according to the characteristics of the subjects. RESULTS: Agreement for ever-never use of any pesticide was 96.4% (kappa 0.61). For both 'years used' and 'age at the first use' of overall pesticides, high agreement was obtained (ICC: 0.88 and, 0.78, respectively), whereas those of 'days used' and 'hours used' were relatively low (ICC: 0.42 and, 0.66, respectively). The kappa value for the use of personal protective equipment ranged from 0.46 to 0.59, and hygiene activities came out at 0.19 to 0.37. The agreement for individual pesticide use ranged widely and there was relatively low agreement due to the low response rates. The reliability scores did not significantly vary according to gender, age, the education level, the types of crop or the years of farming. CONCLUSIONS: Our results support that carefully designed, self-reported information on ever-never pesticide use among farmers is reliable. However, the reliability of data on individual pesticide exposure may be unstable due to low response rates and needs to be refined.

Production of recombinant human von Willebrand factor in the milk of transgenic pigs.

Von Willebrand factor (vWF), a large multimeric glycoprotein present in blood plasma, is a blood protein of the coagulation system. It is defective in von Willebrand disease and is involved in a large number of other diseases, including thrombotic thrombocytopenic purpura-hemolytic uremic syndrome and heyde's syndrome. We have developed a line of transgenic swine harboring recombinant human von Willebrand factor (rhvWF) cDNA through microinjection of fertilized one-cell pig zygotes. Expression of rhvWF in the mammary gland and secretion of rhvWF into the milk of the transgenic swine were confirmed by immunohistochemical and western blot analyses, respectively, and rhvWF proteins were detected in milk from all lactating founder females at concentrations that were 28- to 56-folds greater than that in circulating human plasma. The amino acid sequence of rhvWF protein in the transgenic pig milk matched that of vWF produced from human blood plasma. This study provides evidence that production of rhvWF from transgenic pig milk is a potentially valuable technology and can be used as a cost-effective alternative in clinical applications.

Recombinant human erythropoietin produced in milk of transgenic pigs.

We have developed a line of transgenic swine harboring recombinant human erythropoietin through microinjection into fertilized one cell pig zygotes. Milk from generations F1 and F2 transgenic females was analyzed, and hEPO was detected in milk from all lactating females at concentrations of approximately 877.9+/-92.8 IU/1 ml. The amino acid sequence of rhEPO protein in the transgenic pig milk matched that of commercial rhEPO produced from cultured animal cells. In addition, an F-36 cell line, which proliferates in the presence of hEPO or commercial EPO, was induced to synthesize erythroid by extracts from tg sow milk. This study provides evidence that production of purified rhEPO from transgenic pig milk is a potentially valuable technology, and can be used as a cost-effective alternative in clinical applications as well as providing other clinical advantages.