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Dental technicians are exposed to various dusts in working laboratories. This study was conducted to measure level of silica in the respirable dust generated from dental fixed prosthodontics manufacturing processes using Fourier Transform Infrared Spectroscopy (FTIR), and to compare their occurrence of respiratory symptoms with that of non-dental hospital workers (control group). Respirable dusts were personally sampled from dental technicians working at dental laboratories in Seoul Korea according to NIOSH Method 0600. Fifty personal samples were obtained during porcelain or polishing process and weighed by a gravimetric method. 3 highest for the porcelain and polishing process, respectively. Level of silica contents in the dust was 0.81% and 1.66% for the porcelain and polishing process, respectively. The level of silica contents and silica concentration were significantly different between the two processes. Comparing prevalence of respiratory symptoms between non-smoking seventeen dental technicians and thirty-five control workers, wheezing and rhinorrhea were significantly more manifested in the dental technicians than the controls. Total frequency of respiratory symptoms was also significantly higher in the dental technicians than the controls.

ObjectivesDetermining the work-relatedness of lung cancer developed through occupational exposures is very difficult. Aims of the present study are to develop a decision tree of occupational lung cancer.Methods153 cases of lung cancer surveyed by the Occupational Safety and Health Research Institute (OSHRI) from 1992-2007 were included. The target variable was whether the case was approved as work-related lung cancer, and independent variables were age, sex, pack-years of smoking, histological type, type of industry, latency, working period and exposure material in the workplace. The Classification and Regression Test (CART) model was used in searching for predictors of occupational lung cancer.ResultsIn the CART model, the best predictor was exposure to known lung carcinogens. The second best predictor was 8.6 years or higher latency and the third best predictor was smoking history of less than 11.25 pack-years. The CART model must be used sparingly in deciding the work-relatedness of lung cancer because it is not absolute.ConclusionWe found that exposure to lung carcinogens, latency and smoking history were predictive factors of approval for occupational lung cancer. Further studies for work-relatedness of occupational disease are needed.

Objectives: This study was conducted to investigate problem drinking and analyze factors associated with alcohol use among female firefighters, as well as to provide useful data for management of alcohol use by female firefighters. Methods: The study includeed 1,587 female firefighters from throught Koea. Data were collected from June to July in 2008 using self-administered questionnaires including a general questionnaire, work related questionnaire, the Alcohol Use Disorders Identification Test (AUDIT), the Korean Occupational Stress Scale Short Form (KOSS-26), and the Center for Epidemiologic Studies Depression Scale (CES-D). Among 1,263 female firefighters (75.6%) surveyed, the results of 1,084 qualified questionnaires (70.5%) were analyzed using the chi-square test, Fisher's exact test, and multiple logistic regression. Results: The prevalence of problem drinking (AUDIT score ≥8) in female firefighters was 12.5%. Multiple logistic analysis showed that being single, smoking and depression were correlated with problem drinking. Single female firefighter, present smokers and individuals positive for symptoms of depression had OR values of 2.11, 17.58 and 1.76, respectively. Conclusions: Three factors were found to influnce the occurrence of problem drinking. Accordingly, smoking related education, counseling to cope effectively with depression and health promotion programs that consider psychological effects of job stress are needed to reduce work related factors that lead to problem drinking by female firefighters.

Surface iron on a mineral particle may be a major mediator of mineral-dust-induced toxicity, because iron on the surface of the particle acts as a Fenton catalyst to produce hydroxyl radical from hydrogen peroxide. Desferrioxamine (DF), an iron chelator, might inhibit the process of silica-induced pulmonary reaction. To test this assumption, we investigated the protective effect of DF on lipid peroxidation of cell membrane, production of inflammatory cytokine, and fibroblast proliferation by crystalline silica for an in vitro model. The Fenton activity of silica was decreased by preincubation with DF. Marked decreases in malondialde-hyde (MDA) levels were seen in the DF-treated silica group compared with the untreated group. DF inhibited not only silica-induced release of tumor necrosis factor-α (TNF-α) and interleukin-8 (IL-8) from A549, but also fibroblast proliferation. The therapeutic effect of DF on experimental silicosis in rat was also studied using total cell count with differential percentage in bronchoaiveoiar lavage fluid, the amount of hydroxyproline in lung, and examination of a histologic section. DF significantly reduced inflammation and fibrosis compared with the untreated control. From these results, we concluded that DF might play a role in the inhibition of silica-induced pulmonary reaction.