Whole body vibration exposure of the train drivers working for State Railway Lines is assessed by referring to ISO standard 2631 -1 and EU directive 2002/44/EC. The vibration measurements were done in the cabins of suburban and intercity train drivers. Suburban train driver performs his job usually in standing posture. Whereas intercity train driver works generally in seated (bending forward) posture and exposed to longer periods of continuous vibration, compared to suburban train drivers. The mean accelerations, a, along lateral, y, and vertical, z, directions measured on the driver seat (on the cabin floor) of the intercity (suburban) train were 1.4a y = 0.55 (0.28) m/s2 and a z = 0.65 (0.23) m/s2. Daily exposure action values suggested in EU directive are exceeded in case of intercity train drivers and their exposure falls within the health caution zone of ISO 2631-1. Intercity train drivers are therefore under the risk of having spinal disorders. A health surveillance plan requiring every five years the reassessment of the state of the spinal system of train drivers is suggested. As an early preventive measure, extended work day or more than one shift in a day is advised to be discouraged.
PCB153 (2,2',4,4',5,5'-hexachlorobiphenyl), a non-coplanar PCB and the congener most widely distributed in the environment, was orally administered to pregnant Sprague-Dawley (Crj: CD (SD) IGS) rats from gestation day 10 through 16 at doses of 0 (control), 16 and 64 mg/kg body weight. Female pups were sacrificed at 1, 3, 6, and 9 wk, and at 1 yr of age to evaluate the differences in brain neurotransmitters and their metabolites between PCB153-exposed and control groups. Brain levels of norepinephrine (NE), 3-methoxy-4-hydroxyphenylglycol (MHPG), dopamine (DA), 3,4-dihydroxyphenylacetic acid (DOPAC), homovanillic acid (HVA), serotonin (5HT), 5-hydroxyindoleacetic acid (5HIAA), acetylcholine (ACh), and choline (Ch) in discrete brain regions or in whole brain were measured. At 1 to 3 wk after birth, brain levels of DA, DOPAC, HVA, 5HT and 5HIAA in PCB-exposed groups were higher than those of the control group. At 9 wk after birth, DA turnover was reduced in half of the four brain areas examined (forebrain and hindbrain), and 5HIAA levels were increased in all brain areas in the PCB-treated group compared to those of the control group. At 1 yr after birth, the levels of DA, DOPAC, and HVA in the hippocampus, hypothalamus, and medulla oblongata were lower in the PCB-exposed groups than in the control group. Prenatal exposure to PCB153 stimulated the turnover of 5HT neurons in the brain of female offspring at early stages (1 to 9 wk) of development. On the other hand, the turnover of DA neurons in the PCB-exposed groups was reduced in late stages (9 wk to 1 yr) of development compared with that of the control group. The brain neurotransmitters of dams treated with PCB were assayed at 3 wk after delivery (15 wk old), and decreases in DA, DOPAC, and HVA were observed. PCB153 reduced the activity of DA neurons in the brain of dams. These results are discussed in relation to health effects observed in humans exposed to PCBs.
This study examined the relationship between coping skills, working hours, and psychological health among Japanese daytime workers. Self-administered questionnaires were mailed to a randomly selected sample of 2,000 workers who were members of a pre-recruited market research panel. A total of 1,821 participants responded (response rate=91.1%). Participants completed a questionnaire regarding working hours, coping skills, and psychological health (negative emotions, fatigue, and concentration/activity levels). Analyses of covariance were conducted to determine the relations of number of working hours, coping skills, and their interactions to psychological health with control for sex, age, drinking, job type, and employment type. Results revealed that working hours were significantly associated with fatigue and concentration/activity levels. High levels of instrumental support and positive reframing were significantly associated with low levels of negative emotions, fatigue, and concentration/activity levels. High levels of self-blame, denial, substance use, venting, self-distraction, religion, and behavioral disengagement were significantly associated with high levels of negative emotions, fatigue, and concentration/activity levels. This study suggests that improving coping skills such as using instrumental support or positive reframing may reduce the adverse health effects of long working hours.
The objective of this study was to assess the occupational exposure of jeepney drivers to selected volatile organic compounds (VOCs) in Manila, Philippines. Personal sampling was conducted on 15 jeepney drivers. Area sampling was conducted to determine the background VOC concentration in Manila as compared to that in a rural area. Both personal and area samples were collected for 5 working days. Samples were obtained using diffusive samplers and were analyzed for 6 VOCs (benzene, toluene, ethylbenzene, m,p-xylene and o-xylene) using gas chromatography. Results showed that the average personal exposure concentration of jeepney drivers was 55.6 (±9.3), 196.6 (±75.0), 17.9 (±9.0), 72.5 (±21.1) and 88.5 (±26.5) μg/m3 for benzene, toluene, ethylbenzene, m,p-xylene and o-xylene, respectively. The urban ambient concentration was 11.8 (±2.2), 83.7 (±40.5) and 38.0 (±12.1) μg/m3 for benzene, toluene and o-xylene, respectively. The rural ambient concentration was 14.0 (±6.0) and 24.7 (±11.9) μg/m3 for toluene and o-xylene, respectively. The personal samples had significantly higher (p<0.05) concentrations for all selected VOCs than the urban area samples. Among the area samples, the urban concentrations of benzene and toluene were significantly higher (p<0.05) than the rural concentrations. The personal exposures for all the target VOCs were not significantly different among the jeepney drivers.
Dust can be produced by almost all mining operations in underground coal mines and seen all around the mine. Different occupational groups get exposed to different dust levels and in order to minimize the probability of developing coal workers' pneumoconiosis (CWP), it is necessary to investigate the workers exposed to dust. This study aimed to evaluate the dust concentration conditions in underground coal mines and also the occupational health risks associated with exposures to respirable dust. The data obtained from the dust measurement studies conducted in various underground coal mines between the years 1978-2006 was evaluated by using analysis of variance (ANOVA) and Tukey-Kramer procedure. In the statistical analyses, the comparison of dustiness between mines and their mining regions were made by using the average dust concentration values. In addition, the numbers of workers with doubtful pneumoconiosis diagnosis were evaluated according to the occupational job category by using the number of the workers with the job illness. It was concluded that the production regions have the higher dust concentration levels and the CWP is mostly diagnosed in the workers working in production regions.
This report aims to provide an overview of the intensity of work and work satisfaction in Korea by comparing the first Korean Working Conditions Survey with the results of the fourth European Working Conditions Survey in 2005. According to the comparison, Korean workers work longer hours than workers in the majority of EU countries. However, work intensity in the EU 27 was 1.5 times stronger than Korea. In Korea, the rate of violence, bullying and harassment in the workplace is much lower than the EU 27, but in terms of work satisfaction, EU workers responded more positively than Korean workers. The amount of leave in Korean workers was much lower than the EU counterparts, yet the average number of accident-related or other work-related leaves was greater in Korean workers than workers in the EU. The pattern of exposure to physical factors, namely the most frequent hazards, such as, repetitive movement and painful or tiring posture, is similar in Korean and EU workers. However, the proportion of each exposure is larger in Korean workers than EU workers. In Korea, the most frequently reported work-related symptoms are musculoskeletal disorders followed by stress and fatigue. These patterns are quite similar in Korea and EU countries.
In the last decades there was an increase in stress at work and its effects on workers' health. These issues are still little studied in the electric utility sector. This study aims to evaluate factors associated with stress at work and to verify its associations with health status among workers of an electric company in São Paulo State, Brazil. A cross-sectional study was conducted with 474 subjects (87.5% of the eligible workers). Data were collected using self-reported questionnaires. A descriptive analysis, a multiple linear hierarchical regression analysis and a correlation analysis were performed. The majority of participants were males (91.1%) and the mean age was 37.5 yr. The mean score of stress level was 2.3 points (scale ranging from 1.0 to 5.0). Hierarchical multiple analyses showed that: regular practice of physical activities (p=0.025) and individual monthly income (p=0.002) were inversely associated with stress level; BMI was marginally associated with the stress level (p=0.074). The demographic characteristics were not associated with stress. Stress at work was significantly associated with physical and mental health status (p<0.001). To improve health of electric utility workers, actions are suggested to decrease stress by remuneration and an appropriate practice of physical activity aiming reduction of BMI.
The main purpose of this study was to assess the pulmonary reactions associated with exposure to raw materials used in ceramic production (RMCP). This was a cross sectional study in which 33 male workers with current exposure to RMCP and 20 healthy male unexposed workers (referent group) were interviewed and respiratory symptom questionnaires were administered to them. Furthermore, they underwent chest X-ray and lung function tests. Additionally, personal dust monitoring for airborne inhalable and respirable dust was carried out at dusty areas of the industry. To determine the chemical composition, possible silica phases and SiO2 contents of dust samples, they were analyzed by both X-ray diffraction (XRD) and X-ray fluorescence (XRF) techniques. Demographic and socioeconomic variables of both groups were similar, except that referent individuals were, to some extent, older and heavier than their exposed counterparts. Personal dust monitoring showed that the concentrations of inhalable and respirable dust were very high and dust contained large amounts of crystalline silica. Additionally, respiratory symptom questionnaires revealed that exposed workers, compared to their unexposed counterparts, had higher prevalences of cough, wheezing, phlegm and shortness of breath. Likewise, significant decrements in some parameters of pulmonary function were noted and most of the exposed subjects showed abnormalities in their chest radiographs. These data provide further evidence in favor of the notion that exposure to RMCP, probably due to their silica contents, is associated with respiratory symptoms, radiographic abnormalities and functional impairments.
A questionnaire survey was done to examine the associations between the dimensions of safety climate and the nurses' motivation toward patient safety. Excluding nursing directors, a total of 371 full-time female Japanese nurses (registered nurses and licensed practical nurses) working in 6 hospitals of fewer than 250 beds were analyzed. The average age was 35.6 yr (range, 20-69). For the safety climate, factor analysis (the principal factor method and promax rotation) was performed, and factors with an eigenvalue of≥1 were extracted. Seven dimensions were extracted by factor analysis as follows: "Opportunities for nursing education", "Reporting", "Fatigue reduction", "Superiors' attitudes", "Nursing conditions", "Communications with physicians", and "Relationships among nurses". We subsequently examined the associations between the dimensions of the safety climate and "Nurses' motivation to prevent mistakes". Multiple linear regression analysis showed that "Nurses' motivation to prevent mistakes" was significantly associated with "Reporting", "Nursing conditions", and "Communications with physicians". It is necessary to improve the reporting system in hospitals. It is also necessary to improve on reducing improper communications with physicians. And appropriate nursing conditions must be actualized and maintained.
Unintentional sleep and performance impairment due to extended wakefulness are often the cause of traffic and work accidents. Therefore, large-scale screening instruments assessing the ability to resist falling asleep during monotonous tasks are needed. The current widespread computer use in industrial and home settings offers the possibility to use software-based instruments as an alternative for expensive hardware interfaces to assess sleep resistance. Therefore, we propose a software-based sleep resistance task based on the procedure of the Oxford SLEep Resistance test (OSLER): the Behavioral Sleep Resistance Task (BSRT). In order to validate this instrument we submitted 36 healthy individuals to four 40-min sleep resistance challenges during a night of extended wakefulness (14, 16, 18 and 20 h). Subjective sleepiness was assessed by means of the Karolinska Sleepiness Scale and a Visual Analogue Scale for sleepiness/alertness and objective sleepiness by means of a 4-min EEG-monitored fixation task. Our results show significant correlations of BSRT hit ratio, error profiles and sleep onset latency variables with subjective sleepiness and of BSRT hit ratio and 3-6 error profiles with High-Beta Central EEG activity. Additionally, using a distribution- and scale-free sensitivity index, we found that subjective sleepiness measures are the most sensitive to the effects of sustained wakefulness, closely followed by the BSRT hit ratio and BSRT error profile 3-6.
This study investigated the visual fatigue and musculoskeletal discomfort for wheelchair users in a VDT data entry task. Eight Chinese male wheelchair users were recruited as participants to perform 9 different experimental combinations. Three screen heights and three screen inclinations were evaluated. Visual fatigue was measured using the change in critical fusion frequency (CFF), near point accommodation (NPA) and a visual complaint questionnaire. Musculoskeletal discomfort was estimated using the rating of perceived exertion (RPE). Each participant performed a data-entry task within a 30 min period using random orders. All participants during the data-entry operation used the upright posture with the participant's lower and upper arms forming right angles. The results showed that the screen height and screen inclination significantly affected visual fatigue and musculoskeletal discomfort. On average, the optimal screen height choice for wheelchair users was at eye-level height or 5 cm below eye level with a vertical screen inclination.
A push-pull ventilation system is effective for hazardous material exhaustion. Although a push-pull ventilation system has advantages over a local exhaust hood, some laborious adjustments are required. The pertinence of the adjustments is uncertain because it is difficult to evaluate the performance of a push-pull ventilation system quantitatively. In this study, a measurement of the capture efficiency of a push-pull ventilation system was carried out by means of a tracer gas method. The capture efficiency decreased to 39.3-78.5% when blockage material, a dummy worker and a cross draft, were set in the ventilation zone, but the efficiency was 95.1-97.9% when the cross draft was stopped. The results suggest that the uniform flow of a push-pull ventilation system will detour a blockage and the performance of the system will not be reduced unless a cross draft disturbs the uniform flow.
The aim of this cross-sectional study was to compare the blood lead levels of apprentices working in lead-related industries with those of non-apprentice controls and to evaluate the influence of such occupational exposure. The study was conducted between October 2004 and June 2005 in Bursa, Turkey. Subjects included 231 apprentices and 252 male controls, age ranging from 14-19 yr old. Inductively coupled plasma mass spectrometry (ICP-MS) was used to analyze blood lead levels. The overall mean blood lead level was 3.62 μg/dl (95% CI 3.39-3.85), the apprentice mean was 4.99 μg/dl (95% CI 4.60-5.38), and the control group mean was 2.37 μg/dl (95% CI 2.22-2.51). The blood lead level of apprentices was significantly higher than that of controls (p<0.05). Results show that occupational exposure increases the blood lead levels of apprentices, although the impact on their immediate health is low. Measurement of blood lead levels of apprentices should be taken periodically, and a regular medical surveillance program should be established.