Journal of Occupational Health and Epidemiology

194-201

Authors: K Samimi * , H Asilian , K Khasedar , A Khavanin

Background: 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. Materials and 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. Results: 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”. Conclusions: 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.

211-217

Authors: A Ghanbary Sartang * , M Ashnagar , E Habibi , S Sadeghi

Background: 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. Materials and Methods: 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. Results: The results of the assessment workload using RSME and NASA-TLX index of nurses showed that nurses' 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). Conclusions: 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.

226-234

Authors: M Emkani * , N Hashemi Nejad , H Jalilian , M Gholami , N Sadeghi , S Rahimimoghadam

Background: 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. Materials and Methods: 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. Results: 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. Conclusions: 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.

245-252

Authors: M Tehrani , A Khavanin * , H Asilian

Background: 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. Materials and Methods: 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. Results: 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) and liver/body weight ratio compere to control. The mean serum ALP & ALT level in the co-exposure group was significantly higher than control (P<0.001). Our findings indicated that acute styrene inhalation did not significantly change liver enzymes (AST, ALT) compared to control group (P> 0.050). Conclusions: 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.

129-134

Authors: E Bateni , A Rabiei , N Sabzikari , A Ghanbarzadegan *

Background: This study was performed to evaluate periodontal status in patients with cardiovascular disease (CVD) and assessment of periodontal diseases prevalence in these patients. Materials and Methods: In this cross-sectional study, data on 100 patients were collected with mean age of 51 ± 11 years. The case group included of 50 patients with confirmed CVD who referred to Ali-ibn Abi Talib hospital of Rafsanjan, Iran. Control group included 50 healthy volunteer subjects with no history of systemic diseases that referred to oral medicine diagnosis department of Rafsanjan Dental School. Plaque index, bleeding point index, clinical attachment loss, pocket depth and number of loosed teeth were assessed in this study. Results: Plaque index, clinical attachment loss, pocket depth and number of lost teeth in the target group were more than the control group (P < 0.05). There was no significant difference in bleeding point index between the two groups. Conclusions: Patients who suffer from CVD had a higher risk for periodontal disease. So oral health instructions for this group of patients should be considered more.

143-150

Authors: MM Yaghooti Khorasani * , M Shakerian , M Irannezhad

Background: The majority of individuals who visit the dentist are anxious. They are usually capable of controlling their anxiety. However, this fear sometimes creates great problems for the patient and dentist such as lack of visiting the dentist for treatment, incorrect diagnosis due to lack of appropriate communication between the patient and dentist, and finally, reduction of oral health level. The purpose of this study was to determine the level of dental fear and anxiety in students of Rafsanjan University of Medical Sciences, Rafsanjan, Iran, and its relationship with oral and dental health status in the 2010-2011 academic year. Materials and Methods: This descriptive study was conducted using the Dental Anxiety Scale-Revised (DAS-R), Dental fear Scale (DFS), and the decayed, missing, and filled teeth (DMFT) index checklist. The study was performed on 300 students of Rafsanjan University of Medical Sciences, enrolled during 2005-2011. The participants were selected through stratified random sampling based on the population of each department (medicine, nursing and midwifery, dentistry, and paramedicine). The DMFT, DAS-R, and DFS scores along with other gathered data were analyzed using chi-square test in SPSS software. Results: Among the participants, 82 individuals were medical students, 44 were dentistry students, 53 were nursing and midwifery students, and 121 were paramedical students. In addition, 173 subjects were women and 127 were men. Moreover, 49.3% of students had dental fear and 24.8% had dental anxiety. Among women, 32.4% had dental anxiety and 54.3% had dental fear, while among men, 14.2% had dental anxiety and 40.2% had dental fear. Conclusions: According to the obtained results, variables such as sex, marital status, field of education, history of dental visit, painful previous treatments, and dental anxiety in the family had an effect on DAS-R and DFS scores. Moreover, there was a significant relationship between DMFT index and level of fear and anxiety; with the increasing of dental fear and anxiety, DMFT also increased.

160-167

Authors: A Shirvani , R Vazirinejad , M Rezaeian *

Background: Acquired immune deficiency syndrome (AIDS) is a fatal viral disease which can affect the patient’s immune system and render the patient susceptible to opportunistic infections. In recent years, the number of women with HIV acquired through sexual transmission has increased. Therefore, due to the importance of quality of life (QOL) among these women and the impact of violence and social support on their QOL, this study can assist in the recognition of effective factors on QOL of these patients. Materials and Methods: The study population of this descriptive study consisted of all patients with Human immunodeficiency virus infection/AIDS (HIV/AIDS) who had medical records at the Behavioral Disorders Counseling Center of Shiraz, Iran. To assess QOL, violence, and social support among these patients, the World Health Organization Quality of Life (WHOQOL) scale and the Domestic Violence Questionnaire (DVQ) plus Social Support Questionnaire (SSQ) were used. The collected data were analyzed using Independent two-sample t-test, ANOVA, and correlations. Results: The QOL and SSQ scores of single individuals were higher compared to other groups and violence was lower in this group. The QOL and SSQ scores of residents of rural areas were lower compared to residents of urban areas. Moreover, the violence score of this group was higher. The QOL and SSQ scores of individuals with higher educational level and better economic status were higher than other groups, but their violence score was lower. Conclusions: Total mean QOL, violence, and social support scores were assessed in the present study. Based on the correlation found between these variables, it can be concluded that women with HIV/AIDS require more social support so that their QOL, which is one of the main determinants of health, can be improved.

176-181

Authors: F Mohseni Moghadam , M Tashakori , B Shahidi Zandi , M Hadavi * , V Akbarpoor , F Kazemi , M Moosavi

Background: Laboratory wastes are one of the environmental issues of developing countries and cause diseases and epidemics. Laboratory waste management is planned with the aim of preventing unfavorable effects on human health and the environment. The aim of the present study was to determine the status of medical waste management in clinical laboratories affiliated with Rafsanjan University of Medical Sciences, Iran, in 2015. Materials and Methods: The present study was conducted through a census in all clinical laboratories of Rafsanjan University of Medical Sciences. Data were collected using a checklist that was designed and confirmed by the Iranian Health and Treatment Ministry. After administrative coordination, the checklist was completed through visits and interviews. The collected data were analyzed using descriptive tests in SPSS software. Results: The results showed that, in 40% of cases, individuals responsible for the collection of waste had received the necessary training. In addition, in 28.6% of cases, containers were labeled in order to determine the type of waste inside the container. In 57.1% of laboratories, there was no list of chemicals which must not be mixed during waste collection. The waste was disinfected using an autoclave in only 14.3% of cases. Conclusions: In the present study, the waste classification operation of the majority of laboratories was incomplete. In order to reduce contamination in these centers, measures must be taken regarding the disposal of waste at the site of its production. Furthermore, individuals responsible for collection and transference of waste must comply with personal protection measures.

63-71

Authors: M Shariati * , A Naderi

Background: Individuals, who spend most of their time sitting, are at 30% more risk of suffering from lumbar disc than other people. One of the causes of pain in the lumbar region is musculoskeletal disorders (MSDs). MSDs are the most common and most costly injuries in occupational, administrative, and academic environments. Therefore, the aim of this study was to investigate the relationship between chair dimensions and the prevalence of MSDs in female students. Materials and Methods: This descriptive-analytic and cross-sectional study was conducted on 101 female students of Ahvaz Branch, Islamic Azad University, Iran. Dimensions of chairs (width and length of chair seat, backrest length, and etc.) were measured using a tape measure and goniometer. Lordosis and kyphosis were evaluated using a Gravity line. Data were analyzed using chi-square test. All p values of less than 0.05 were considered significant. Results: The subjects’ mean age was 27.12 years and 50% of the subjects had normal BMI. There was no significant relationship between ergonomic dimensions of chairs and kyphosis abnormality (P < 0.05). There was a significant relationship between lordosis abnormality and height of backrest (P = 0.04), seat to ground height (P = 0.04), seat width (P = 0.02), height of armrest (P = 0.04), and armrest to seat height (P = 0.04). Conclusions: According to the results, the dimensions of chairs that were used in the university were not favorable. This could lead to the presentation of some MSDs. It is recommended that the anthropometric dimensions of the consumer society be considered before the purchasing of chairs.

83-88

Authors: F Mohseni Moghadam , M Tashakori , B Shahidi Zandi , M Hadavi * , E Ranjbar , Sh Shahidi Zandi

Background: Methicillin-resistant Staphylococcus aureus (MRSA) is resistant to most antibiotics and is an important pathogen of nosocomial infections. The prevalence of community (CA-MRSA) and hospital acquired methicillin-resistant S. aureus (HA-MRSA) infection is increased. In this study we investigated the frequency of MRSA colonization and its antibiotic susceptibility in students of Rafsanjan University of Medical Sciences, Iran. Materials and Methods: In this cross-sectional study, we evaluated 200 nursing, midwifery and paramedical students. Nasal swabs were taken from all cases and were cultured on a blood medium agar. Methicillin resistance was confirmed using Oxacillin and cefoxcitin disks. Inducible clinadamycin resistance was identified using D-zone test. Demographic and specific information were collected by questionnaire. Data were analyzed by chi-square test. Results: Among 200 studied cases, the frequency of nasal carriers for S. aureus was 5%. Six (60%) out of 10 S. aureus isolates were MRSA strains. Fifty percent of MRSA and 25% of methicillin-susceptible S. aureus (MSSA) were resistant to clindamycin. Four out of 6 strains of MRSA and 1 of the MSSA strains were resistant to erythromycin and D test was positive in 50% of cases. Conclusions: Nasal carriers of the resistant strains of S. aureus are always a serious threat to themselves and others. The rate of MRSA colonization, especially clindamycin-resistant strains, was high among studied cases, emphesizing the need for screening S. aureus.

98-104

Authors: A Ghanbary Sartang , M Ashnagar * , E Habibi , S Sadeghi

Background: Musculoskeletal pain accompanied by psychological problems leads to reduced health efficiency. On the other hand, work-related anxiety and depression is another important factor that could result in reduced productivity in organizations and physical and mental problems in personnel. Musculoskeletal disorders (MSDs) are the most common occupational health problems that have high costs and lead to productivity loss in military personnel. The purpose of this study was to evaluate the association of anxiety and depression with MSDs among military personnel in 2016. Materials and Methods: This descriptive-analytic and cross-sectional study was conducted on 70 military personnel in July 2016 through convenience sampling method. The data collection tools used were the Cornell Musculoskeletal Discomfort Questionnaire (CMDQ)‎ and Goldberg Anxiety and Depression ‎Scale. Data analysis was conducted using descriptive statistics, Pearson correlation test, and ANOVA in SPSS software. Results: The highest prevalence of MSDs was observed in the back (48%), thoracic spine (41%), and shoulder (37%). The Goldberg Anxiety and Depression Scale scores showed that anxiety and depression were at a medium level. The Pearson correlation test showed a significant correlation between anxiety (P = 0.01) (r = 0.79) and depression (P = 0.01) (r = 0.76), and MSDs; with increase in anxiety and depression, MSDs also increased. Conclusions: The results of this study showed that anxiety and depression have a direct relationship with MSDs. Therefore, interventions must be carried out for MSDs prevention such as reducing physical and psychological job demands, and reducing anxiety and depression level among military personnel.

112-120

Authors: Z Zamanian , Y Mehrifar *

Background: Today, the growth of major industries depends on their appropriate interaction with small and medium enterprises (SMEs). In Iran, SMEs have 49 or fewer employees. The present study was an attempt to present an overall view of the condition of professional health and safety in such industries in order to gain information regarding activities related to occupational health and safety. Materials and Methods: This study was a cross-sectional enquiry, in which 541 SMEs in Arak, Iran, were selected through systematic sampling and questionnaires were mailed to these companies. The questionnaires were sent to the occupational health units of the health centers in order to investigate target industries. The collected data was entered into SPSS software and analyzed using descriptive statistical methods. Results: The total response rate of the SMEs was 59%. Approximately, 59.2% of the enterprises monitored their workplace every 6 months in order to reduce and control risks. In addition, 44% of the target enterprises had written and regulated health and safety policies. With respect to safety, 64.7% of the enterprises had included health and safety training in the work plans of all employees at all levels. Moreover, 72.3% trained their staff on how to use self-protection devices, and 69.7% of the target SMEs had safety and technical protection committees. Conclusion: Welfare facilities and health management in SMEs were satisfactory. With respect to safety management, it can be inferred from this study that the essential safety and health factors for SMEs include announcing and investigating accidents, and education safety, because 70% of the target enterprises performed these activities.

1-9

Authors: A Zaranejad , O Ahmadi * , E Yahyaei

Background: One of the challenges in construction is the occurrence of numerous accidents. In this regard, risk assessment can play an important role in reducing accidents. The aim of this study was to prepare comprehensive and quantitative checklists to determine the potential hazards in the construction phase. Materials and Methods: The present descriptive and analytical study was carried out on petrochemical projects in the south of Iran in 2014. After the inspection of more than 50 construction projects, two types of technical and managerial checklists were designed. The managerial and technical checklists were designed with seven and 32 major subjects, respectively. Finally prepared checklist and ET&BA method were compared in term of their risk identification capability. Results: The checklist and ET&BA methods, respectively, identified 300, 75, 125, and 48, and 107, 25, 12, and 0 risks related to hardware, design, mismanagement, and human error. Conclusions: The checklist method can identify and assess human errors, while the ET&BA method cannot. Moreover, this method was more efficient than the ET&BA technique in identification and assessment of hardware-related, design-related, and managerial risks. Moreover, the duration and cost of implementation of checklist method were significantly lower than ET&BA method. This technique can be introduced as a quantitative risk assessment method in construction phases of projects and its weaknesses can be improved by future studies.

20-25

Authors: Y Mehrifar , A Eskandarnia , H Pirami , H Mardanparvar *

Background: Laboratory activities must be planned and organized carefully because of the danger they may cause. The purpose of this study was to assess students’ awareness and comprehension of chemical hazard warning signs at the Departments of Chemistry of Razi University, Kermanshah, Iran. Materials and Methods: This descriptive study was carried out to assess students’ awareness and comprehension of chemical hazard warning signs. Data were collected from 175 students enrolled in Chemistry Laboratory Classes during the second semester of the year 2012-2013. The participants were selected randomly. The collected data was entered into SPSS software and analyzed using descriptive statistical methods. Results: The results of the study revealed that the majority of the respondents (81%; n = 143) were familiar with hazard signs of laboratory chemicals. After obtaining information on their level of awareness about potential hazards of laboratory chemicals, the respondents were also requested to match chemical properties with the corresponding labels or pictograms. Conclusions: The results indicated that the students had a high level of familiarity and understanding of hazard warning signs. The study also surveyed the preferred labeling technique and revealed that the majority favored the use of both colors and signs.

31-37

Authors: M Shakerian * , F Sardari , T Kordafshari

Background: Children are the most sensitive and vulnerable group in terms of tooth decay. Any change or improvement in health-related knowledge and behavior in this group can have long-term and significant impacts on the health of the future generation. Thus, the present study was conducted with the aim to determine the relationship of knowledge of oral health-related issues with the decayed, missing, and filled teeth (DMFT) index in 12-year-old students of Rafsanjan, Iran, in 2016. Materials and Methods: This descriptive, cross-sectional study was performed on 460 students (230 boys and 230 girls) of 12 years of age from 10 elementary schools in Rafsanjan. The subjects were randomly selected. Data were collected through clinical examination, interviews, and a questionnaire. The questionnaire consisted of two parts; the first part contained a demographic characteristics form, and the second part contained the DMFT index and questions on knowledge of oral health-related issues. Data were analyzed using independent t-test, ANOVA, chi-square, and the Pearson correlation coefficient (α = 0.05). Results: Mean DMFT index and knowledge score of the students were 2.66 ± 1.40 and 5.43 ± 1.82, respectively. Students with higher knowledge had lower DMFT index. Moreover, mean knowledge score of students with homemaker mothers was significantly higher compared to students with working mothers. Conclusion: The results of this study suggested a positive significant relationship between knowledge of oral health-related issues and DMFT index in 12-year-old students of Rafsanjan.

45-52

Authors: R Vazirinejad , A Jafarzadeh , SM Yassini , A Rahimdel , AR Sayadi *

Background: Multiple sclerosis (MS) is one of the most common chronic diseases of the central nervous system. The aim of this study was to determine the effectiveness of psychological training combined‎ with gradual muscular stress relaxation technique on QOL of patients with MS. Materials and Methods: This triple-blind, controlled, clinical trial was conducted on 60 patients with MS who were members of the Multiple Sclerosis Society of Yazd Province, Iran. The subjects were selected through convenience sampling method and with the consideration of the inclusion criteria. The participants were randomly divided into 2 groups of experimental (30 persons) and control (30 persons). The experimental group received 12 sessions of psychological training combined with gradual muscular stress relaxation technique (2 sessions per week), but the control group received no intervention. The data collection tools used consisted of a demographic characteristics form and the Multiple Sclerosis Quality of Life-54 (MSQOL-54) ‎ questionnaire. The questionnaires were completed before, immediately after, and 3 months after the training. Data were analyzed using the statistical tests of student’s t-test, Pearson correlation, and repeated measures. Results: QOL score in the experimental and control groups were 50.86 ± 14.78 and 56.25 ± 13.09 before the intervention (p=0.141), 68.49 ± 11.81 and 55.76 ± 13.37 immediately after the intervention, and 67.80 ± 11.90 and 55.06 ± 12.83 three months after the intervention, respectively. This difference was statistically significant (P <0.0010). Moreover, repeated measures statistical test showed a meaningful increase in QOL score in the experimental group in the 3 measurements (P < 0.0001). Conclusions: The implementation of psychological training intervention combined with gradual muscular stress relaxation method in patients with MS increases QOL. Therefore, it can be used as a beneficial intervention method for improving the QOL of patients with MS.