Ventilation impairment of residents around a cement plant

OBJECTIVES: To identify adverse health effects due to air pollution derived from a cement plant in Korea. The ventilation impairment in residents around a cement plant was compared to another group through a pulmonary function test (PFT). METHODS: From June to August of 2013, both a pre and post-bronchodilator PFT was conducted on a "more exposed group (MEG)" which consisted of 318 people who lived within a 1 km radius of a cement plant and a "less exposed group (LEG)" which consisted of 129 people who lived more than 5 km away from the same plant. The largest forced expiratory volume in a one second (FEV1) reading and a functional residual capacity (FVC) reading were recorded after examining the data from all of the usable curves that were agreed upon as valid by PFT experts of committee of National Institute of Environmental Research. The global initiative for chronic obstructive lung disease (GOLD) criteria for COPD, defined the FEV1/FVC ratio == 0.7 and FVC% predicted < 80% were as the restrictive type. The FVC% predicted value was estimated using Korean equation. We compared the proportion of lung function impairments between the MEG and the LEG by using a chi-square, and estimated the OR of obstructive and restrictive ventilation impairments by logistic regression. RESULTS: The obstructive type impairment proportion was 9.7% in the MEG, whereas it was 8.5% in the LEG. The restrictive type was 21.6% in the MEG which was more than the 12.4% of the LEG. The odds ratio (OR) of total ventilation impairment in the MEG was 2.63 (95% CI 1.50 ~ 4.61) compared to the LEG. The OR of obstructive type in the MEG was 1.60 (95% CI 0.70 ~ 3.65), the smoking history was 3.10 (CI 1.10 ~ 8.66) whereas OR of restrictive type in the MEG was 2.55 (95% CI 1.37 ~ 4.76), the smoking history was 0.75 (95% CI 0.35 ~ 1.60) after adjusting for sex and age. Level of exposure to particulate played a role in both types. However, it appeared to be a significant variable in restrictive type, while smoking history was also an important variable in obstructive type. CONCLUSION: Although this study is a limited cross-section study with a small number of subjects, ventilation impairment rate is higher in the MEG. There might be a possibility that it is due to long-term exposure to particulate dust generated by the cement plant.

Cardiovascular Disease Risk of Bus Drivers in a City of Korea

OBJECTIVE: To prevent the occurrence of CV events such as MI and stroke among professional drivers in Korea, bus drivers were compared to other occupations through the Framingham risk scoring system (FRS) or metabolic syndrome (MS) of cardiovascular disease (CVD) risk assessment methods. METHODS: In October 2012, a health examination survey was conducted for 443 male bus drivers in a big city. Their CVD risk factors were compared to those of a 'total employed' (A group) and 'crafts and machine operators' (B group) extracted from Fifth Korea National Health and Nutrition Examination Survey (KNHANES, 2010) data by using FRS and MS. We calculated proportions of the CVD risk factors distribution between bus drivers and the A, B groups by the bootstrapping method. The Odds ratio (OR) between CV event risk combining MS with CHD equivalent risk of FRS and occupational factors like shift patterns and professional driving duration/age ratios (PDAR) of bus drivers was calculated through multinominal logistic regression. RESULTS: The proportion of BMI > or = 25 kg/m2 was 53.9% and waist circumference > or = 90cm was 40.9% among bus drivers. Hypertension and MS prevalence of bus drivers was 53.3%, 49.9% which is higher than 17.6%, 22.6% in the A group and 19.7%, 23.8% in the B group respectively. OR of high CV event risk in alternate shift was 2.58 (95% CI 1.33~5.00) in comparison with double shift pattern and OR in PDAR > or = 0.5 was 2.18 (95% CI 1.15~4.14). CONCLUSION: Middle aged male drivers in a big city of Korea stand a higher chance of developing CV event than other professions of the same age.

Occupational Stress and MMPI-2 Profile of Workers in Some Plants Undergoing Labor Dispute / 대한산업의학회지

OBJECTIVES: To identify changes in relationships with superiors or colleagues at work and family members and social networks at home, based on occupational stress and psychological characteristics in during the process of restructuring some plants undergoing a long-term labor dispute. METHODS: This study invested 213 workers involved in a long-term labor dispute using the KOSS (Korean Occupational Stress Scale) and the MMPI-2 (Minnesota Multiphasic Personality Inventory) and questionnaires. The KOSS and MMPI-2 scores in accordance with aggressiveness of trade union activity and changes in human relationships were compared. In addition, the odds ratio of whether there were differences in health behavior (perception of health status, smoking, alcohol abuse, medical treatment) and the absenteeism rate was calculated by logistic regression analysis. RESULTS: For members of the aggressiveness of trade union activity group, the rate at which the relationship between superiors or colleagues deteriorated was high, as was the total KOSS score, occupational system and lack of reward score of KOSS subclass. The depression subclass score of MMPI-2 was generally high, while the score of hypochondriasis, hysteria, psychopathic deviate, hypomania was high, and social introversion was low in the active group. In cases in which there were high score of psychopathic deviate, hypomania and paranoia, there were also signs of negative health behavior. CONCLUSIONS: Occupational stress caused by a long-term labor dispute, accompanied with depression can result in an aggressive, hostile and vulnerable personalities and have a negative impact on health behavior.