Effects of Simultaneous Exposure to Smoking and Welding Fume on Pulmonary Function Tests in Spot Welders.

BACKGROUND: The respiratory effects of fume exposure during spot welding may aggravate some environmental risk factors such as tobacco smoking. Fume exposure and smoking have negative effects on pulmonary function tests (PFTs). This study assessed the simultaneous effects of smoking and welding fume on spirometry tests in spot welders. MATERIALS AND METHODS: This cross-sectional study was conducted on 667 spot welders and 1000 assemblers in an automotive manufacturing plant. Spirometry was carried out on all the participants under standard conditions and according to the American Thoracic Society Clinical Practice Guidelines and indices including FEV1, FVC, FEV1/FVC, FEF 25-75, and PEF were measured and compared between two groups of the study population including workers of spot welding and assembling. RESULTS: It was found that the effect of simultaneous exposure to smoking and welding fume was aggravated on the PFT indices including the FEV1 percent, FEV1/FVC, the FEV1/FVC percent, the PEF percent, FEF25-75, and the FEF25-75 percent, but not on indices such as FVC, the FVC percent, and PEF. CONCLUSION: Simultaneous exposure to smoking and welding fume resulted in a reduction in some spirometry indices, causing respiratory airway obstruction in the spot welders. Occupational safety and regular medical examinations with shorter intervals in smoking spot welders can prevent acute respiratory effects of exposure to smoking and welding fume.

Predictive factors for return to work after lumbar discectomy.

Background. Lower back pain (LBP) is one of the most common complaints leading to disability and work absence. This study was performed to determine the rate and contributing factors of return to work in the postoperative phase after lumbar discectomy. Methods. This cohort study was performed among 142 patients attending the orthopedics spine clinic of a teaching hospital during 2016. Initially, the demographic and occupational characteristics and Oswestry disability index (ODI) were fulfilled, and patients were followed with regard to time off, work return and type of job after surgery. Results. 113 participants (79.5%) returned to work in 3 months. Male gender, higher literacy, non-manual job, less physical activity, non-smoking, formal work agreement, lower working hours and higher income were associated with return to previous work. Also, shorter preoperative duration of LBP, longer hospital stay, lower severity of LBP, lower ODI score and poor perceived prognosis of return to work were associated with return to previous work. Conclusions. Return to work after discectomy is seen in more than two-thirds of patients and is related to factors such as pain intensity and body mass index. However, return to previous versus modified job is a multifactorial issue.

Prospective cohort study on the social determinants of health: Tehran University of Medical Sciences employees` cohort (TEC) study protocol.

BACKGROUND: In this study, the association between the social determinants of health (SDH) as well as other health risk factors and outcomes will be evaluated at different socioeconomic layers. METHODS/DESIGN: This is a prospective cohort study that was launched in January 2018 on Tehran University of Medical Sciences' employees. The initial enrolment phase will continue up to March 2021, or until a sample size of 5500 is reached. In addition to annual phone-calls, the participants will be followed thrice at 5-year intervals. Data are collected through blood and urine samples, complete physical examination, anthropometric evaluation, and the completion of questionnaires related to SDH, such as socioeconomic status and social capital, history of diseases, lifestyle (including, nutrition, physical activity, cigarette and hookah smoking), occupational exposures (including psychosocial factors at work and work-family conflicts), and different aspects of physical, mental and occupational health as health outcomes. The association between independent variables and health (objective or subjective) are examined using multiple models and by controlling the confounding effects. Moreover, the trend in lifestyle changes and its impact on health are evaluated. DISCUSSION: Our study will explore the key social determinants as well as other factors including socioeconomic status and social capital, history of diseases, lifestyle and occupational exposures that affect health. This will provide social and occupational health decision-makers and stakeholders with new and valuable evidence in an era in which we are witnessing huge changes in lifestyle.

A Burden Assessment of Occupational Exposures in Iran, 1990-2010: Findings from the Global Burden of Disease Study 2010.

BACKGROUND: The present study describes the burden of occupational diseases in Iran based on the results of the Global Burden of Disease study conducted in 2010 (GBD 2010). This study aimed to determine the burden of occupational diseases in Iran based on the results of GBD 2010. It is a cross-sectional study. METHODS: Disability-adjusted life years (DALYs) of occupational diseases were calculated based on the prevalence rates obtained through model estimation, as well as GBD 2010 disability weights and mortality rates obtained from different data registry systems of Iran. Causal association criteria application to select risk outcome pairs, estimation of exposure to each risk factor in the population, estimation of etiological effect size, selection of a counterfactual exposure distribution, risk assessment, and identification of burden attributable to each risk factor were the main conducted statistical steps. RESULTS: There was an increasing trend of DALYs (710.08/100,000 people in 1990 and 833.00/100,000 people in 2005) followed by a slight decrease (833.00/100,000 in 2005-784.55/100,000 people in 2010). A total of 50.4% and 36% of total DALYs per 100,000 people were due to the adverse effects of musculoskeletal disorders and work-related injuries, respectively. CONCLUSIONS: Musculoskeletal disorders and work-related injuries are the most important adverse consequences of work-related risks that require urgent interventions to be controlled. Male workers (15-25 years and over 60) with the highest DALYs and mortality rates need more training programs, safety regulations, and higher level of protection support. In spite the decreasing trend of occupational disease related DALYs and death rates in Iran in recent years, a long-term effort is required to maintain the currently decreasing trend.

Medical radiation workers' knowledge, attitude, and practice to protect themselves against ionizing radiation in Tehran Province, Iran.

BACKGROUND: Medical radiation workers are potentially at a risk of unwanted ionizing radiation exposures. This study assessed the radiation protection knowledge, attitude, and practice (RP-KAP) of health-care workers who are occupationally exposed to radiation regarding protecting themselves from radiation. MATERIALS AND METHODS: This study was cross-sectional in design and was carried out in 16 hospitals affiliated to the Tehran University of Medical Sciences between May and September 2014. Total health-care workers who were occupationally exposed to radiation comprising 670 individuals were included in the study based on census sampling method. In total, 413 individuals consented to complete an anonymous 32-item questionnaire comprising single best choice questions with a numerical value assigned to each correct answer. Each set of RP-KAP questions was scored and categorized as poor, medium, and good. The effect of independent variables for prediction of RP-KAP was explored using linear regression analyses. RESULTS: A significant number of participants had poor RP-knowledge (78.9%), RP-attitude (70.7%), and RP-practice (32.4%). Based on linear regression analyses, it was found that field of study (ß = 0.1, P = 0.001), marital status (ß = -0.14, P = 0.01), and level of education (ß = 0.2, P < 0.001) were the predictors of higher RP-knowledge. In-service RP-training (ß = 0.1, P = 0.04) was associated with an increased RP-attitude. Being a woman (ß = 0.2, P < 0.001) and longer years of experience with radiation (ß = 0.2, P < 0.001) were significantly related to better practice. CONCLUSION: In-service training with appropriate qualified and up-to-date materials based on radiation workers' educational needs and approved protocols and guidelines is recommended.

Predictors of early return to work after a coronary artery bypass graft surgery (CABG).

OBJECTIVES: Identifying factors predictive of early return to work in patients who underwent a coronary artery bypass graft surgery (CABG). MATERIAL AND METHODS: Two hundred twenty-six working patients who volunteered and underwent a primary coronary artery bypass surgery between September 2013 and May 2014 were selected for the study and followed up for 6 months. Predictors of early return to work (RTW) (within 2 months) were analyzed from variables in a prospectively collected database and the 36-Item Short Form Health Survey (SF-36) questionnaire carried out in the hospital and rehabilitation center as well as from the follow-up performed via the phone. RESULTS: One hundred and two (45.1%) and 155 (68.9%) patients returned to work within 2 and 3 months after the surgery, respectively. Furthermore, 196 patients (87.1%) returned to work within 6 months after the surgery. In the univariate analysis, demographic or socioeconomic factors (such as age, level of education, income), occupational factors (such as occupation type, working hours per week, duration of the preoperative absence from work), psychological factors (such as a patient's concern about adverse health effects of RTW, feeling depressed, a patient's attitude towards his/her ability to RTW and a patient's perception of his/her job stress level) and medical factors (such as serum troponin T and creatine kinase MB (CKMB) level, pump time in surgery, co-surgery and dyslipidemia history) had a statistically significant correlation with early return to work. The patients who early returned to work had significantly higher scores in 3 domains on the SF-36 questionnaire (used for assessing the patients' quality of life), compared to those who did not return to work early (including physical functioning, role limitations due to physical health and pain). CONCLUSIONS: In the present study we identified 4 new medical factors that could be used as predictors of early return to work after CABG. These factors are: normal serum troponin T level, shorter pump time in surgery, normal mean arterial pressure (MAP) before the surgery and higher serum magnesium (Mg) levels. Int J Occup Med Environ Health 2016;29(6):947-957.

Radiation Protection Knowledge, Attitude and Practice (RP-KAP) as Predictors of Job Stress Among Radiation Workers in Tehran Province, Iran.

BACKGROUND: In recent years, much attention has been paid to occupational stress, but relatively little or no research has been conducted on the influence of knowledge, attitude, and practice of radiation protection (RP-KAP) on job stress among radiation workers. OBJECTIVES: This study aims to assess job stress among health care workers in Iran who are occupationally exposed to radiation in order to determine the effects of KAP on self-protection against radiation on their job stress. MATERIALS AND METHODS: The population in this descriptive cross-sectional study comprised 670 healthcare workers, including 428 staff with a degree in radiology and 242 other medical personnel who were working in 16 hospitals affiliated with Tehran University of Medical Sciences (TUMS) in Tehran, Iran. The census method was used to sample the workers. In total, 264 staff with a degree in radiology and 149 other medical personnel completed the job content questionnaire (JCQ) and the RP-KAP questionnaire from May to November 2014. RESULTS: The prevalence rate of job stress was 22.5% based on calculation formulas and possible scores on the JCQ. Sex, RP-knowledge, attitude, practice, and in-service training predicted 41.8% of the variance in job stress. According to the results of the binary logistic regression, workers with higher scores on knowledge (OR = 0.82, 95% CI: 0.75 - 0.90), attitude (OR = 0.71, 95% CI: 0.63 - 0.82), and practice (OR = 0.78, 95% CI: 0.72 - 0.86) and those who had participated in training programs had significantly lower rates of job stress (OR = 0.51, 95% CI: 0.28 - 0.93). CONCLUSIONS: The effects of RP knowledge, attitude, and practice on job stress were significant. In order to reduce job stress in radiation environments, ongoing training programs related to self-care and protection principles are recommended.

Urinary 8-hydroxy-deoxyguanosine as a biomarker of oxidative DNA damage in employees of subway system.

Exposure to air pollutants, steel dust or other occupational and environmental hazards as oxidative stress have adverse effects on subway workers' health. Oxidative stress generates an excessive amount of reactive oxygen species (ROS) and Oxygen Free Radicals during their work time in the tunnels. Once DNA is repaired, Urinary 8-hydroxy-deoxyguanosine (8-OHdG) is excreted in the urine. Therefore, urinary level of 8-OHdG can reflect the extent of oxidative DNA damage. The aim of this study was to document the oxidative stress caused by exposure to these hazards by measuring 8-OHdG in workers urine. We collected urine samples of 81 male subway workers after their working shift. The concentration of urinary 8-OHdG was measured by ELISA method. We used linear regression analysis to compare the level of urinary 8-OHdG as a biomarker of oxidative stress between workers in tunnels and other staff. The mean concentration of urinary 8-OHdG for workers in the tunnel was 58.05 (SD=28.83) ng/mg creatinine and for another staff was 54.16 (SD =26.98) ng/mg creatinine.  After adjustment for age, smoking, driving and a second job in a linear regression model, the concentration of 8-OHdG for the exposed group was significantly higher than unexposed group (P=0.038). These findings confirm that the concentration of urinary 8-OHdG for workers who work in tunnels was significantly higher than the other staff. Additional investigations should be performed to understand that which ones of occupational exposures are more important to cause oxidative stress.

Sleep quality of professional firefighters.

BACKGROUND: Firefighting is a unique job with contradictious demands that expose firefighters to many well documented causal factors of sleep debt, but no studies in Iran and only a few worldwide studies have investigated their sleep quality while sleep problems may lead to catastrophes especially in critical service workers. The aim of this study is to evaluate sleep quality and its related factors among a sample of professional Iranian firefighters. METHODS: Using simple random sampling method in a cross-sectional study, 427 personnel of fire and rescue service were invited. They completed the Persian version of Pittsburgh Sleep Quality Index (PSQI) and a data collection sheet about their demographic and occupational features during an individual face to face interview in central office and firehouses throughout Tehran. Response rate was 88.7%. RESULTS: The mean ± SD global PSQI score was 7.97 ± 3.77. Sleep latency was the component of PSQI with the greatest degree of abnormality. 69.9% of participants were poor sleepers. Interestingly, we found no significant differences between sleep quality of shift workers and non shift workers. Using multiple logistic regression analysis, only having another job, smoking and years of job experience were predictors of poor sleep. CONCLUSIONS: In comparison with adult population of Tehran, sleep quality deterioration is notably more common in Tehran firefighters which require health promotion interventions to prevent its serious adverse outcomes.

Epigastric and umbilical hernia; work relatedness and return to work.

Abdominal wall hernia is common but reliable scientific data about its work relatedness is very limited and inconsistent. In this paper, a less common type of abdominal wall hernia in a 30 year old male worker is presented with recurrence after first surgery when he returned to work. In contrast with almost all kinds of hernia, a lifelong limitation for heavy lifting was recommended. It seems that contrary to popular belief, work relatedness of abdominal wall hernia is seriously doubtful, although conclusive evidences are not enough. It is preferable to make decisions cautiously for return to heavy duties of work after surgery of large umbilical, umbilical & epigastric or incisional hernia, while avoiding recommendations for long days off work after surgery of any hernia.

Effects of training course on occupational exposure to bloodborne pathogens: a controlled interventional study.

BACKGROUND: One of the serious occupational concerns in health care workers (HCWs) is exposure to blood/body fluids that can transmit blood borne pathogens such as human immunodeficiency virus and hepatitis B and C viruses. We are reporting the effects of training course and surveillance on the rate of needle stick injuries (NSIs) among HCWs at an educational hospital in Iran. AIMS: To evaluate the effects of training course on the rate of NSIs and its reporting. METHODS: We selected two hospitals (A&B) based on their similarities in wards and facilities then asked the managers of these two hospitals to participate in our study. We established a new occupational health center and conducted a training course at hospital A on 2010 and compared it with control group (hospital B). The data from 2009 to 2011 was collected, analyzed to compare pre and post intervention rates. RESULTS: DURING STUDY PERIOD NURSES SUSTAINED THE HIGHEST NUMBER OF INJURIES (HOSPITAL A: n=80; 66.1% and hospital B: n=64; 35.4%). The incidence rate of NSIs in hospital A was 7.16 NSI/100FTE/YEAR before the intervention which was increased to 12.06 after the intervention. In hospital B this rate was 6.05 during three years. CONCLUSIONS: The study revealed remarkable increase in the incidence rate of NSIs after the intervention. This is being achieved by meticulous surveillance, training course and improving awareness.

Relationship between exposure to industrial noise and serum lipid profile.

Aim of our study was to investigate the effects of exposure to industrial noise on serum lipid profile among workers who are exposed to noise at work. In a historical cohort study, we recruited 154 and 146 male workers as high and low level noise exposure groups respectively. We defined workers with at least one year exposure to noise level more than 90 dB as high exposure group, and those with exposure to less than 80 dB as low exposure group. Afterwards, in the fasting blood specimens of participants we measured serum Triglyceride (TG), total Cholesterol (TC), high and low density lipoprotein (HDL and LDL). Mean of TG, TC, HDL and LDL for low exposure group were 148, 189, 38 and 103 mg/dl and for high exposure group were 237, 189, 37 and 104 mg/dl respectively. Mean serum TG between two groups was different. Even after adjustment for age, BMI, smoking and work hours per week, serum TG among high exposure group was 89 mg/dl higher than low exposure group and this difference was statistically significant (P = 0.00). There was no significant difference between two groups in TC, LDL and HDL levels. This study did not find a statistically significant relationship between exposure to noise and serum TC, LDL and HDL, but TG in two groups was different and this difference was statistically significant.

Evaluation of exposure to the airborne asbestos in an asbestos cement sheet manufacturing industry in Iran.

Iran imports nearly 55,000 tons of Chrysotile asbestos per year and asbestos cement (AC) plants contribute nearly 94% of the total national usage. In the present study, airborne asbestos concentrations during AC sheet manufacturing were measured. The fiber type and its chemical composition were also evaluated by scanning electron microscopy (SEM), with energy-dispersive X-ray analysis. Airborne total fiber concentrations of 45 personal samples were analyzed by phase contrast microscopy. The results have highlighted that 15.5% of samples exceed the threshold limit value (TLV) established the American Conference of Governmental Industrial Hygienists, which is 0.1 fiber per milliliter (f/ml). Personal monitoring of asbestos fiber levels indicated a ranged from 0.02 ± 0.01 to 0.16 ± 0.03 f/ml. The geometrical mean was 0.05 ± 1.36 f/ml, which is considerably lower than the TLV. SEM data demonstrate that the fibrous particles consisted, approximately, of Chrysotile (55.89%) and amphiboles (44.11%). We conclude that the industrial consumption of imported Chrysotile asbestos is responsible for the high airborne amphibole asbestos levels in the AC sheet industry. More research is needed to improve characterization of occupational exposures by fiber size and concentration in a variety of industries.

Antinuclear antibody and rheumatoid factor in silica-exposed workers.

A lot of workers in industries such as foundry, stonecutting, and sandblasting are exposed to higher than permissible levels of crystalline silica. Various alterations in humoral immune function have been reported in silicosis patients and workers exposed to silica dust. The aim of this study was to measure antinuclear antibody (ANA) and rheumatoid factor (RF) levels in foundry workers exposed to silica and to compare them with a control group without such exposure. ANA and RF were measured in 78 exposed and 73 non-exposed workers, and standard statistical methods were used to compare them. The two groups did not significantly differ in age and smoking. Mean work duration of the exposed and non-exposed workers was (14.9+/-4.72) years and (12.41+/-6.3) years, respectively. Ten exposed workers had silicosis. ANA was negative in all workers in either group. Its mean titer did not differ significantly between the exposed and control workers [(0.39+/-0.15) IU mL(-1) vs. (0.36+/-0.17) IU mL(-1), respectively]. RF was positive in two workers of each group. Other studies have reported an increase in ANA and RF associated with exposure to silica dust and silicosis.In contrast, our study suggests that exposure to silica dust does not increase the level of ANA and RF in exposed workers.

Topical mitomycin-C for treatment of partially-excised ocular surface squamous neoplasia.

BACKGROUND: This study was conducted to determine the treatment outcome of incompletely removed, histopathologically documented ocular surface squamous neoplasia with mitomycin-C. METHODS: Through an interventional case series, 17 eyes of 17 patients presented with incompletely removed ocular surface squamous neoplasia were treated according to a protocol using two to three alternate seven-day courses of 0.04% mitomycin-C. Clinical recurrence was re-treated with the same protocol. All patients had weekly follow-up visits to the end of the treatment course, then biweekly visits for three months, and monthly visits, thereafter. RESULTS: The mean+/-SD follow-up period was 30.76+/-4.4 (range: 24.5 - 41) months. Five patients (29.4%) experienced recurrence after the initial treatment; four of them responded to retreatment and were disease-free till the end of follow-up. Survival analysis with Kaplan-Meier method was performed. Taking into account four recurrences, the 41-month nonrecurrence rate was 70.6%. However, including four of five patients with recurrence who responded to retreatment, the final outcome in survival analysis was 94.1% nonrecurrence for 41 months of follow-up. All patients reported mild to moderate redness and irritation which were controlled with lubricants and mild corticosteroid eye drops. No serious ocular or systemic side effects were observed. CONCLUSION: Point zero four percent (0.04%) mitomycin-C drop used as two to three alternate seven-day courses seems to be a safe and effective treatment for ocular surface squamous neoplasia.

In chronic low back pain, low level laser therapy combined with exercise is more beneficial than exercise alone in the long term: a randomised trial.

QUESTION: Is low level laser therapy an effective adjuvant intervention for chronic low back pain? DESIGN: Randomised trial with concealed allocation, blinded assessors and intention-to-treat analysis. PARTICIPANTS: Sixty-one patients who had low back pain for at least 12 weeks. INTERVENTION: One group received laser therapy alone, one received laser therapy and exercise, and the third group received placebo laser therapy and exercise. Laser therapy was performed twice a week for 6 weeks. OUTCOME MEASURES: Outcomes were pain severity measured using a 10-cm visual analogue scale, lumbar range of motion measured by the Schober Test and maximum active flexion, extension and lateral flexion, and disability measured with the Oswestry Disability Index on admission to the study, after 6 weeks of intervention, and after another 6 weeks of no intervention. RESULTS: There was no greater effect of laser therapy compared with exercise for any outcome, at either 6 or 12 weeks. There was also no greater effect of laser therapy plus exercise compared with exercise for any outcome at 6 weeks. However, in the laser therapy plus exercise group pain had reduced by 1.8 cm (95% CI 0.1 to 3.3, p = 0.03), lumbar range of movement increased by 0.9 cm (95% CI 0.2 to 1.8, p < 0.01) on the Schober Test and by 15 deg (95% CI 5 to 25, p < 0.01) of active flexion, and disability reduced by 9.4 points (95% CI 2.7 to 16.0, p = 0.03) more than in the exercise group at 12 weeks. CONCLUSION: In chronic low back pain low level laser therapy combined with exercise is more beneficial than exercise alone in the long term.

Interaction of smoking and occupational noise exposure on hearing loss: a cross-sectional study.

BACKGROUND: Noise is the most common hazardous agent at workplaces. Noise induced hearing loss (NIHL) has been known since the industrial revolution. Although NIHL is permanent, irreversible and frequent, it is preventable. The economic costs of NIHL have been estimated to be about billions of dollars. Besides, cigarette smoking is a common habit worldwide, and according to some recent studies smoking and noise may act in common causal pathways for hearing loss. METHODS: A cross-sectional study was designed to study the effect of smoking on NIHL in 206 male smoker workers and 206 male non-smoker workers in a large food-producing factory, in which workers were exposed to noise levels exceeding 85 dBA. To determine noise exposure level, we used sound level measurements reported by industrial hygienists.A qualified audiologist assessed hearing acuity by using standardized audiometric procedures assuring at least 14 h of noise avoidance. RESULTS: We observed that the percentage of workers with hearing threshold differences of greater than or equal to 30 dB between 4000 Hz and 1000 Hz in both ears were 49.5% and 11.2% in smoker and non smoker groups, respectively (Odds ratio = 7.8, 95% CI = 4.7-13), and the percentage of workers with a hearing threshold of greater than 25 dB at 4000 Hz in the better ear were 63.6% and 18.4% in smoker and non smoker groups, respectively. This difference was statistically significant after adjustment for age and exposure duration. CONCLUSION: It can be concluded that smoking can accelerate noise induced hearing loss, but more research is needed to understand the underlying mechanisms. Accurate follow up of smoker workers who are exposed to noise levels exceeding 85 dBA is suggested. Smokers should periodically attend educational courses on "smoking cessation", especially in noisy workplaces.