OBJECTIVETo study the effect of occupational stress on cardiovascular function of different vocational population.

METHODSThe occupational stressors, risk factors of cardiovascular diseases were investigated by questionnaire in 839 people with 4 kinds of jobs. Blood pressure, sugar, and lipid were detected at the same time.

RESULTSBlood pressure were higher in the groups of old age, long standing and teachers, and the abnormal rate of blood pressure was 21.69%. There was no difference in abnormal ECG among ages, standing and occupation, and the abnormal rate of ECG was 19.07%. Job control, job demands, job responsibility, role in a job and shift work were the main stress factors affecting systolic and diastolic blood pressure. More conflict in job, less chance of participation, severe job loads were the risk factors of primary hypertension. Accident due to job responsibility, job responsibility, role in a job were the main risk factors of abnormal electrocardiograph. Self-respect and activity beyond work were the good modifiers of heart function.

CONCLUSIONOccupational stress has certain effect on cardiovascular function.

Adult ; Blood Pressure ; Electrocardiography ; Female ; Humans ; Logistic Models ; Male ; Occupational Diseases ; physiopathology ; Stress, Psychological ; physiopathology

OBJECTIVETo understand the toxic effects of manganese exposure on health by measurement of manganese concentration and occupational health inspection among workers in an enterprise exposed to manganese, and to provide a basis for occupational disease control.

METHODSThe air concentrations of manganese in 12 workplaces where workers often stayed were measured by typical sampling; occupational health inspection was performed among a total of 538 workers in the enterprise by cluster sampling.

RESULTSThe average concentrations of manganese in the workplace from 2011 to 2013 were 0.179 mg/m(3), 0.122 mg/m(3), and 0.082 5 mg/m(3), respectively, indicating a significant decrease in manganese level within the three years by rank-sum test (P < 0.05). The results of health inspection showed that 165 (30.7%) out of 538 workers had abnormal indices, and the incidence of autonomic nervous system abnormalities reached 32.7% (176/538). There was no correlation between manganese concentration in the workplace and the incidence of abnormal indices in health inspection, while the manganese concentration in the workplace was positively correlated with the incidence of autonomic nervous system symptoms (r = 0.718, P < 0.05).

CONCLUSIONThe manganese concentration in the workplace is positively correlated with the incidence of autonomic nervous system symptoms. Early exposure to a low level of manganese can induce functional changes and potential damages in the nervous system.

Humans ; Incidence ; Manganese ; analysis ; Nervous System ; drug effects ; physiopathology ; Occupational Diseases ; chemically induced ; epidemiology ; Occupational Exposure ; analysis ; Occupational Health ; standards ; Workplace

OBJECTIVETo assess the impact of work-related musculoskeletal disorders (WRMDs) on work ability among workers.

METHODSA total of 1686 workers in various occupations, such as administration and education, were enrolled as subjects using the random cluster sampling method. The WRMDs and work ability of all subjects were evaluated using standardized Nordic questionnaires for the analysis of musculoskeletal symptoms and the Work Ability Index (WAI) scale, respectively. Comparison of work ability and its classification between the disease group and the non-disease group was performed by paired t test, RxC table χ2 test, and the Wilcoxon rank-sum test. The relationship between work duration and work ability was analyzed by the Spearman correlation test and a multi-level model.

RESULTS(1). The work ability of workers in the disease group was significantly lower than that in the non-disease group (P<0.0 1). (2) There were significant differences in work ability between workers with different work durations (<10 years, 10-20 years, and ≥20 years) (F=22.124, P< 0.01). With the increase in work duration, the work ability of workers declined in both groups, and the work ability of workers in the disease group (Spearman coefficient rs=-0. 172, P<0.01) had a more significant decline than that in the non-disease group (Spearman coefficient rs=-0.104, P<0.01). WRMDs were important risk factors for the decrease in work ability among workers. (3) There were significant differences in constituent ratios and levels of work ability classification between the disease group and the non-disease group (χ2=121.097, P<0.01; Z=-10.699, P<0.01). The proportions of workers with poor and medium work ability in the disease group were significantly higher than those in the non-disease group, while the proportion of works with excellent work ability in the disease group was significantly lower than that in the non-disease group. The similar characteristics in constituent ratios and levels of work ability classification could be found between the disease group and the non- disease group in various occupations (P<0.01).

CONCLUSIONWRMDs have a harmful effect on the work ability of workers, and the work ability of workers substantially declines with the increase in exposure time (work duration).

Humans ; Musculoskeletal Diseases ; physiopathology ; Occupational Health ; Occupations ; Risk Factors ; Surveys and Questionnaires ; Work Performance

OBJECTIVETo evaluate the role of muscle fatigue in the pathogenesis of high prevalence of low back pain(LBP) in drivers who work at high altitude, in order to seek the effective measures for prevention and treatment of LBP.

METHODThe spectral electromyographic(EMG) changes during isometric contraction of erector spinalis to fatigue in 26 drivers in the field were consecutively recorded after daily driving for 5 days. The relationship between the decline of median frequency and the development of the back extensor fatigue were analyzed.

RESULTSThe decline rates of EMG median frequency of the erector spinalis on 1-5 working day [(-0.258 +/- 0.087), (-0.248 +/- 0.070), (-0.256 +/- 0.097), (-0.267 +/- 0.093), (-0.274 +/- 0.081)%/s respectively] were significantly different from that of baseline measured before work [(-0.175 +/- 0.114)%/s, P < 0.05 or P < 0.01]. A positive correlation was also found between the decline rate and the working time(r = -0.809, P < 0.05).

CONCLUSIONThe high prevalence of LBP in the drivers working at high altitude is due to acumulative fatigue of back extensor resulting from long-distance driving, lack of proper rest, decrease of muscle endurance and increase of liability to fatigue, consequently leading to the muscle dysfunction and finally LBP.

Altitude ; Automobile Driving ; Electromyography ; Humans ; Low Back Pain ; etiology ; physiopathology ; Muscle Fatigue ; physiology ; Occupational Diseases ; etiology

OBJECTIVES: This study aimed to evaluate occupational symptoms and chemical exposures of nail salon technicians. METHODS: Work-related symptoms of nail salon technicians in Daegu City were surveyed using a researcher-administered questionnaire, and responses were compared to those of non-exposed office workers as controls. Personal exposure level of airborne volatile organic compounds was also monitored using passive samplers. RESULTS: A total of 159 subjects in 120 salons were interviewed. Average work-shift concentrations of 13 chemicals were measured for 50 workers from 30 salons using personal passive samplers. The most frequently reported respiratory or neurologic symptoms by nail shop technicians compared to controls were nose irritation (odds ratio [OR], 54.0; confidence interval [CI], 21.6 to 134.8), followed by headache (OR, 9.3; CI, 4.7 to 18), and throat irritation (OR, 4.3; CI, 2.2 to 8.5). For eyes and skin, 92% of respondents complained eye irritation (OR, 13.1; CI, 5.7 to 30.1). In musculoskeletal symptoms, workers reported pain or discomfort in shoulders (OR, 20.3; CI, 7.7 to 54) and neck (OR, 19.7; CI, 8.9 to 43.6). From personal measurements, the proportion of exceeding the Korean Occupational Exposure Limit was the highest for acetone with 64%, followed by toluene (50%), butyl acetate (46%), and methyl methacrylate (12%). However, the service was being provided without a proper ventilation system in most surveyed shops. CONCLUSIONS: Based on these findings, it is warranted to have appropriate local exhaust ventilation place to ensure adequate health protection of nail shop technicians as well as customers. At the same time, greater policy interests are warranted in nail care business to protect health of both workers and customers.
Adolescent ; Adult ; Air Pollutants, Occupational/*chemistry ; Eye Diseases/physiopathology ; Female ; Humans ; Interviews as Topic ; Male ; Middle Aged ; Musculoskeletal Diseases/physiopathology ; Occupational Diseases/physiopathology ; Occupational Exposure/*analysis ; Questionnaires ; Republic of Korea ; Respiratory Tract Diseases/physiopathology ; Skin Diseases/physiopathology ; Ventilation ; Volatile Organic Compounds/*analysis ; Workplace ; Young Adult

By implementing epoch-making policies of industrial promotion, the national economy has made a remarkable development. As a result of such economic growth, industrial accidents and occupational diseases have become a serious problem in Korean society. In the presidential order for the execution of the Korean labor standard law, neuritis and other diseases stemming from health impairments due to vibration in industrial processes are designated to be dealt with as vibration diseases. In the case of vibration disease, industrial accident compensation is not effectively paid. In order to investigate vibration hazards of rock-drill operators, the author studied subjective symptoms and did physical function tests on a total of 208 persons (vibration exposed group), who used rock-drills, and 115 persons (control group) who are not using rock-drills at anthracite mines. The results of physical function test are as follows. 1. There is no difference in smoking habits between the vibration exposure group and the control group. 2. In the use of their ear plugs, both the vibration exposed group and the control group showed a low tendency in using the ear plugs. 3. In the prevalence rate of white finger, the vibration exposed group reached 12.5 percent, but only 0.9 percent in the control group. Thus, both groups showed different rates in the initiation of their illness (p < 0.01). 4. The prevalence rate of finger numbness for the vibration exposed group was 23.1 percent, but only 9.6 percent in control group (p < 0.05). 5. In the prevalence rate of insomnia, the vibration exposed group had 22.6 percent and the control group 9.6 percent. Thus, the vibration exposure group showed a higher rate than the control group (p < 0.05). 6. In the vibration sense threshold, the vibration exposed group showed a statistically higher level than the control group (p < 0.01). 7. In the mean value of skin temperature, the control group was higher than the vibration exposed group (p < 0.05). 8. In the amount of perspiration, the exposed group measured higher than the control group (p < 0.01).
Adult ; Coal Mining* ; Human ; Middle Age ; Occupational Diseases/epidemiology* ; Occupational Diseases/physiopathology ; Raynaud's Disease/epidemiology ; Sensory Thresholds ; Smoking ; Vibration/adverse effects*

A growing body of literature has documented that job stress is associated with the development of cardiovascular disease. Nevertheless, the pathophysiological mechanism of this association remains unclear. The purpose of this study is to elucidate the relationship between job stress, heart rate variability, and metabolic syndrome. The study design was cross-sectional, and a total of 169 industrial workers were recruited. A structured-questionnaire was used to assess the general characteristics and job characteristics (work demand, decision latitude). Heart rate variability (HRV) was recorded using SA-2000 (medi-core), and was assessed by time-domain and by frequency-domain analyses. Time domain analysis was performed using SDNN (Standard Deviation of normal to normal interval), and spectral analysis using low-frequency (LF), high-frequency (HF), and total frequency power. Metabolic syndrome was defined on the basis of risk factors being clustered when three or more of the following cardiovascular risk factors were included in the fifth quintile: glucose, systolic blood pressure, high-density lipoprotein cholesterol (bottom quintile), triglyceride, and waist-hip ratio. The results showed that job characteristics were not associated with cardiovascular risk factors. Compared to the lower strain group (low strain+passive+active group), the high strain group had a less favorable cardiovascular risk profile with higher levels of blood pressure, glucose, homocysteine, and clotting factor, but the difference was not statistically significant. The SDNN of HRV was significantly lower in the high strain group than in the low strain group. The prevalence of metabolic syndrome in the lower strain group and high strain group was 13.2% and 23.8%, respectively. In the high strain group, the metabolic syndrome was significantly related to a decreased SDNN. However, we could not find a significant association in LF/HF ratio. This result suggests that decreased HRV found in the high-strain group are not a direct indicator of disease. However, it can induce cardiovascular abnormalities or dysfunctions related to the onset of heart disease among high risk groups.
Adult ; Aged ; *Heart Rate ; Humans ; Male ; Metabolic Syndrome X/*physiopathology ; Middle Aged ; Occupational Diseases/*physiopathology ; Research Support, Non-U.S. Gov't ; Stress, Psychological/*physiopathology

Objective: To expore the correlation between neck disability, neck pain and muscle strength in cervical pondylosis of office worker, and to provide scientific basis for the prevention and treatment of cervical spondylosis. Methods: In April 2021 ,234 patients with cervical spondylotic myelopathy treated in the Subsidiary Rehabilitation Hospital of Fujian University of Traditional Chinese Medicine from April 2015 to April 2017 were selected, the correlation between Neck Disability Index (NDI) score, neck pain and muscle strength was analyzed using the Spearman rank correlation method. Mann-Whitney U test was used to compare the difference of maximum muscle strength of isometric contraction. Results: NDI score was negatively correlated with neck flexion, extension, and muscle strength in the left and right flexion directions (r(s)=-0.164, -0.169, -0.222, -0.176, P=0.012, 0.010, 0.001 , 0.007). In mild and moderate functional disorder patients, the muscle strength in flexion, extension and left and right flexion direction was greater, the difference was statistically significant (P <0.01). Conclusion: There is a negative correlation between cervical functional disorder and cervical muscle strength in office workers, suggesting that strengthening cervical muscle strength may be a way to improve cervical spine function.
Cervical Vertebrae ; Humans ; Muscle Strength/physiology* ; Neck Muscles/physiology* ; Neck Pain/physiopathology* ; Occupational Diseases/physiopathology* ; Range of Motion, Articular/physiology* ; Spondylosis/physiopathology*

Adult ; Chemical and Drug Induced Liver Injury ; Dimethylformamide ; adverse effects ; Formamides ; analysis ; Humans ; Kidney ; physiopathology ; Kidney Diseases ; chemically induced ; physiopathology ; urine ; Kidney Function Tests ; Liver ; physiopathology ; Liver Diseases ; physiopathology ; urine ; Liver Function Tests ; Male ; Middle Aged ; Occupational Exposure

OBJECTIVE: To explore the effect of dust exposure, type of work, age, length of service and duration of dust exposure on pulmonary function in coal miners by pulmonary function tests.
 METHODS: A total of 1 953 coal miners, who received occupational healthy examination and pulmonary function tests during June, 2013 and August, 2014 in Hunan Prevention and Treatment Institute, were enrolled for this study.
 RESULTS: A total of 1 302 miners (66.7%) displayed pulmonary dysfunction, including 1 139 with mild dysfunction (58.3%) and 163 with moderate or more serious dysfunction (8.3%). The risk factors for pulmonary dysfunction were age (OR=1.329, 95% CI: 1.196-1.620), dust exposure duration (OR=1.267, 95% CI: 1.136-1.413) and type of works (mining workers OR=1.156, 95% CI: 1.033-1.293; all P<0.05).
 CONCLUSION The incidence rate of pulmonary dysfunction in coal miners is relatively high in Hunan Province. Most of them are mild dysfunction. The incidence rate of pulmonary dysfunction in mining works is statistically higher than that in other work types. Older workers and long duration-exposed workers are more likely to have pulmonary dysfunction.
China ; Coal Mining ; Dust ; Humans ; Incidence ; Lung ; physiopathology ; Lung Diseases ; epidemiology ; Occupational Exposure ; Respiratory Function Tests ; Risk Factors