Journal of Occupational Health and Epidemiology
Volume:5 Issue: 4, Autumn 2015

Gas refining is a process in which workers are exposed to different chemicals. This study aimed to assess the health risks caused by exposure to these substances in order to determine hazardous jobs and to present controlling methods.
This cross-sectional study was performed on the workers at gas refinery in 2015. The sample included all the staff in operational parts and the selection was by census. To determine the risk of exposure to chemical pollutants, the method proposed by the Department of Occupational Safety and Health of Malaysia was used. Following this procedure, first the materials and processes were identified. Afterwards, risk and exposure rates were calculated. Using these two rates and risk rate formulas for individual chemicals, the exposure was calculated.
The results showed that employees were exposed to 103 different types of chemicals that collectively were causing 162 types of exposure in different jobs. Of the total exposures, 5 percent were evaluated as “inconsiderable risk rate”, 51 percent as low, 30 percent average, 13 percent high, and 1.2 percent as “very high risk rate”.
The highest risk rate of exposure to chemicals in the refinery was related to benzene in stabilizer and topping area shift works (RR = 5) as well as the shift works in feller area and evaporation pools with risk rate of 5, ranking their risk as very high, indicating that corrective actions should start on this hazardous and carcinogenic chemical as soon as possible.

Abstract: (292 Views)
Due to high prevalence of musculoskeletal risk factors among kitchen workers and their role in causing discomfort, the aim of this study was to investigate the effects of ergonomic factors (mental workload and working posture) on musculoskeletal disorders (MSDs) among workers of training hospitals in Qazvin, Iran.
This cross-sectional study was done through census among 60 workers of teaching hospital's kitchens of Qazvin University of Medical Sciences in 2016. Data were collected using pain perception and mental workload questionnaires and Quick Exposure Check (QEC) method was used for posture assessment. Data were analyzed using single and multiple logistic regression tests.
About 85% of the workers reported that their work shift was very heavier than normal. The best and worst exposure score in QEC method were assigned to cooking and trolley responsible tasks, respectively. Seventy percent of working postures were classified in action level 3 (i.e. investigation and changes are required soon) that increased the backache prevalence by nearly about 4 times. Heavy workload in interaction with other influential factors increased the neck discomfort about 5 times and back discomfort by 2.5 times.
Long working hours, heavy workload, stress, high-speed work, long standing and inadequate rest are the factors influencing the increase of MSDs prevalence among the kitchen workers. By increasing numbers of manpower, reducing the workload and working hours and adequate rest, in addition to doing the work properly, MSDs in this group can somehow be reduced.

Mental workload is one of the factors that influence individuals’ performance in the work environment as well as their efficiency and productivity. This study aimed to evaluate the effectiveness of the Rating Scale Mental Effort (RSME) for mental workload in nurses.
This study was descriptive and cross-sectional conducted on 75 nurses. For assessment of mental workload, first NASA task load index (NASA-TLX) and then RSME were measured. After from data gathering, the data were analyzed using SPSS, descriptive statistics, Student’s independent t-test, analysis of variance (ANOVA) and Pearson correlation test.
The results of the assessment workload using RSME and NASA-TLX index of nurses showed that nurse's workload was high. Pearson correlation test regression coefficient showed a good correlation between scores of RSME and NASA-TLX index (r = 0.72) (r2 = 0.51). Also there was no significant association between age and work experience with mental workload score in RMSE (P = 0.09) (P = 0.08) and NASA-TLX index (P = 0.08) (P = 0.06). Student’s t-test showed that no significant relationship was observed between sex and scores of RMSE (P = 0.08) and NASA-TLX index (P = 0.07).
The results of this study showed that RMSE is a good method for assessing mental workload and there was acceptable correlation with NASA-TLX valid indices. RMSE index can be used to assess the mental workload.

Non-specific pain of low back and neck has direct impact on quality of life, active days at work, and health care costs. The purpose of this study was to determine the pain intensity and disability index for low back and neck among dentists.
This cross-sectional study was conducted among 80 dentists (44.6% female and 55.4% male). Dentists pain intensity and low back and neck disability index were evaluated with the self-administered visual analog scale and Oswestry questionnaire, respectively. Statistical data analysis was done using SPSS.
Disability index of low back and neck has been reported equal to 26.6 ± 10.7 and 22.0 ± 8.8, respectively. Also the data showed the average pain intensity of low back and neck to be 75.5 ± 24 and 49.6 ± 19.7. The result showed significant relationship between pain intensity and disability index for low back and neck with body mass index (BMI) and exercise (P According to results, dentists have a high pain prevalence and moderate disability index of low back and neck. Also based on the relationship between the pain and disability index values with BMI and exercise, we recommend practice of relaxation and stretching exercises during breaks in the dentists work schedules to minimize the risk of work-related musculoskeletal disorders among dentists.

Vibration as one of the harmful physical factors is relatively present in a wide range of jobs. Musculoskeletal disorders (MSDs) are among the most prevailing complaints of workers encountering occupational factors for example vibration. Therefore, this study was conducted to investigate vibration and its association with the MSDs in upper limbs of heavy mine vehicles drivers.
This cross-sectional study was conducted, on heavy mine vehicles of Gol-Gohar Sirjan Centre, Sirjan, Iran. In general, 288 drivers with 92 vehicles were working at the mine site. SVAN958 vibration meters and the Nordic Musculoskeletal Questionnaire were used to measure whole body vibration and upper limb MSDs, respectively. Finally, the data were analysed using SPSS.
The highest average equilibrated acceleration was in graders (2.179 m/s2) and drills had the lowest average acceleration (0.479 m/s2). Prevalence of MSDs within past 12 months showed a significant difference in the neck (P = 0.044) and elbow (P = 0.023) between case and control group. The whole body vibration variable was associated with MSDs in the neck (P = 0.020) and wrist/hands (P = 0.030), and with increase in vibration the MSDs showed a 59% increase in neck and 72% in wrist/hands. In multivariate analysis, the whole body vibration variable had a significant relation with MSDs in wrist/hand (P = 0.027) and caused an 83% increase in the risk of MSDs per each unit in wrist/hand.
The prevalence of disorders in studies with short duration is probably not quite visible; however, by increasing the working experience with these vehicles which have higher vibration than standard rates, the chance of developing MSDs increases.

A disease impacts patients’ participation level in their individual and social life through impacting their physical and mental performance. Due to the increasing prevalence of diabetes mellitus (DM), and the importance of patients’ participation and quality of life (QOL) and the determination of the most important aspects affected by the disease in the participation and Quality of Life of patients with type II DM in Rafsanjan, Iran, the present study was conducted.
In this cross-sectional study, 227 patients with type II DM were assessed. The data collection tool consisted of a 2-part questionnaire. The first part was a demographic characteristics checklist. The second part was the Persian version of the Impact on Participation and Autonomy (IPA-p) scale. The IPA-p scale was used to collect data on the subject's participation in their own life. Then, a trained individual completed the demographic checklist through interviews. Subsequently, the subjects were asked to complete the IPA-p scale.The collected data were analyzed in SPSS software. Statistical tests such as t-test and ANOVA were used to compare the obtained means.
The highest level of participation was observed in the age group of 30-49 years, and participation was higher in men, single individuals, and individuals with a good economic status.
The results of the present study suggested the presence of a statistically significant relationship between the participation of patients with type II DM and individual, social, economic factors. Thus, this disease causes a reduction in their participation in different life aspects, and therefore, causes a reduction in QOL. With the consideration of the long-term course of the disease, taking measures to improve individuals’ participation level seems necessary.

Liver is an important organ that responsible for biological detoxification. There are few studies about the effect of co-exposure to organic solvents and noise on hepatic system enzymes. The study aim was to assess the effects of short-term exposure to noise and styrene on rat liver enzymes.
In this experimental study, we studied the liver enzymes of male rats. Twenty-four rats (250±10 g) were divided in four groups (N=6): control (A), noise exposure (100dB) (B), styrene exposure (750ppm) (C), styrene (750ppm) noise (100dB) co-exposure (D). Treatment was performed in an 8 hours/day and 5 day/week order for 2 weeks. Blood samples were obtained for AST, ALT, and ALP investigation. Data analysis was performed in SPSS software.
Calculations based on weighting did not show any significant difference in body weight and liver/body weight ratio in co-exposed group, compared to the control (P>0.050). Noise exposure caused a statistically significant increase both in liver enzymes (ALT, ATP, AST) (P 0.050).
It can be concluded that exposure to noise (100 dB) alone and combined with styrene can cause imbalance in liver enzymes level. Results suggest that liver enzymes are sensitive to noise therefore can be used as a screening method for early diagnosis of hepatic dysfunction for exposed individuals at work places. The current study clearly confirmed that co-exposure to noise and styrene has an additive effect in ALP augmentation.