A high-flux P84 polyimide mixed matrix membranes incorporated with cadmium-based metal organic frameworks for enhanced simultaneous dyes removal: Response surface methodology.

The water sources contaminated by toxic dyes would pose a serious problem for public health. In view of this, the development of a simple yet effective method for removing dyes from industrial effluent has attracted interest from researchers. In the present work, flat sheet mixed matrix membranes (MMMs) with different physiochemical properties were fabricated by blending P84 polyimide with different concentrations of cadmium-based metal organic frameworks (MOF-2(Cd)). The resultant membranes were then used for simultaneous removal of eosin y (EY), sunset yellow (SY) and methylene blue (MB) under various process conditions. The findings indicated that the membranes could achieve high water permeability (117.8-171.4 L/m2.h.bar) and promising rejection for simultaneous dyes removal, recording value of 99.9%, 81.2% and 68.4% for MB, EY and SY, respectively. When 0.2 wt% MOF-2(Cd) was incorporated into the membrane matrix, the membrane separation efficiency was improved by 110.2% and 213.3% for EY and SY removal, respectively when compared with the pristine membrane. In addition, the optimization and modeling of membrane permeate flux and dye rejection was explored using response surface methodology. The actual and model results are in good agreement with R2 of at least 0.9983 for dye rejection and permeate flux. The high flux of the developed MMMs coupled with effective separation of dyes suggests a promising prospect of using P84 polyimide MMMs incorporated with MOF-2(Cd) for water purification.

Evaluating the airborne asbestos dispersion in enclosed parking lots in Iran.

Each time a car's brakes are used, asbestos is dispersed in the air. Breathing the air in enclosed parking lots can expose people working in these places to asbestos. This study aimed to evaluate the airborne asbestos dispersion in enclosed parking lots. In this study, 35 air samples were collected from six enclosed parking lots in Tabriz City. The samples were analyzed quantitatively by phase contrast microscopy (PCM) and qualitatively by a scanning electron microscope (SEM) equipped with an energy-dispersive X-ray analyzer. The mean of fiber concentrations was found 0.155 ± 0.069 PCM f/cc. The SEM data demonstrated that the fibers consisted of synthetic fibers (69.57%) and asbestos (30.43%). Fiber concentrations in many enclosed parking lots in the city were higher than the threshold limit value-time weighted average of the American Conference of Governmental Industrial Hygienists and Occupational Exposure Limits of Iran. However, further investigations are needed to clarify asbestos exposure in such places.

Prevalence and predictors of low back pain among the Iranian population: Results from the Persian cohort study.

BACKGROUND AND OBJECTIVES: Low back pain (LBP) is a common health condition in populations. Limited large-scale population-based studies evaluated the prevalence and predictors of LBP in developing countries. This study aimed to evaluate the prevalence and factors associated with LBP among the Iranian population. METHODS: We used baseline information from the Prospective Epidemiological Research Studies in Iran (PERSIAN), including individuals from 16 provinces of Iran. LBP was defined as the history of back pain interfering with daily activities for more than one week during an individual's lifetime. Various factors hypothesized to affect LBP, such as age, sex, marital status, educational status, ethnicity, living area, employment status, history of smoking, body mass index (BMI), physical activity, sleep duration, wealth score, history of joint pain, and history of morning stiffness in the joints were evaluated. RESULTS: In total, 163770 Iranians with a mean age of 49.37 (SD = 9.15) were included in this study, 44.8% of whom were male. The prevalence of LBP was 25.2% among participants. After adjusting for confounders, the female gender [OR:1.244(1.02-1.50)], middle and older ages [OR:1.23(1.10-1.33) and OR:1.13(1.07-1.42), respectively], being overweight or obese [OR:1.13(1.07-1.19) and OR:1.21(1.16-1.27), respectively], former and current smokers (OR:1.25(1.16-1.36) and OR:1.28(1.17-1.39), respectively], low physical activity [OR:1.07(1.01-1.14)], and short sleep duration [OR: 1.09(1.02-1.17)] were significantly associated with LBP. CONCLUSION: In this large-scale study, we found the lifetime prevalence of LBP to be lower among the Iranian population in comparison to the global prevalence of LBP; further studies are warranted to evaluate the causality of risk factors on LBP.

Prevalence, awareness, treatment, and control of hypertension based on ACC/AHA versus JNC7 guidelines in the PERSIAN cohort study.

In this cross-sectional population-based study, we used the baseline data of the Prospective Epidemiologic Research Studies in IrAN cohort study collected in Iran from 2014 to 2020. The main outcomes were the prevalence of hypertension and proportion of awareness, treatment, and control based on the 2017 ACC/AHA guideline compared to the seventh report of the Joint National Committee (JNC7). Of the total of 163,770 participants, aged 35-70 years, 55.2% were female. The sex-age standardized prevalence of hypertension was 22.3% (95% CI 20.6, 24.1) based on the JNC7 guideline and 36.5% (31.1, 41.8) based on the ACC/AHA guideline. A total of 24,312 participants [14.1% (10.1, 18.1)] were newly diagnosed based on the ACC/AHA guideline. Compared to adults diagnosed with hypertension based on the JNC7 guideline, the newly diagnosed participants were mainly young literate males who had low levels of risk factors and were free from conventional comorbidities of hypertension. About 30.7% (25.9, 35.4) of them (4.3% of the entire population) were eligible for pharmacologic intervention based on the ACC/AHA guideline. Implementation of the new guideline may impose additional burden on health systems. However, early detection and management of elevated blood pressure may reduce the ultimate burden of hypertension in Iran.

Assessment of airborne asbestos exposure at an asbestos cement sheet and pipe factory in Iran.

Iran imports nearly 55,000 metric tons of asbestos per year, and asbestos cement (AC) plants contribute nearly 94% of the total national usage. In the present study, asbestos fiber concentrations during AC sheet and pipe manufacturing were measured by phase-contrast microscopy (PCM) and polarized light microscopy (PLM) in 98 personal air samples. The fiber type and its chemical composition were also evaluated by scanning electron microscopy (SEM) and energy-dispersive X-ray analysis (EDX). Personal monitoring of fiber levels indicated a range from 0.02 to 0.55PCM f/ml (0.02-0.69PLM f/ml). The AC workers' geometric mean asbestos exposure was 0.09 PCM f/ml (0.11 PLM f/ml), with arithmetic mean of 0.13 PCM f/ml (0.16 PLM f/ml). The observed fiber concentrations in many processes were higher than the threshold limit value (TLV) proposed by the American Conference of Governmental Industrial Hygienists (ACGIH), which is 0.1 f/ml. Based on these findings, the PLM values were approximately 25% higher than PCM values. The SEM data demonstrate that fibrous particles contained chrysotile. The thinnest fiber recognized by SEM had a diameter of 0.2µm. Mean exposure exceeded the TLV for asbestos in pipe molding and finishing (100%) as well as sheet molding and finishing (45.5-83.3%). In conclusion exposure control may be needed to be in compliance with the ACGIH TLV and other guidance levels. Also, with regard to PCM limitations for airborne fiber analysis, the use of microscopic methods other than PCM can be used to improve the techniques used presently.

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.

Evaluation of exposure to the airborne asbestos in an automobile brake and clutch manufacturing industry in Iran.

About 2000 tons of chrysotile is used annually to produce friction materials in Islamic Republic of Iran. Approximately, 3000 workers are exposed to the asbestos fibers in the different processes of brake and clutch manufacturing. In the current study, asbestos fiber concentrations during brake and clutch manufacture were measured. This study also evaluated the fiber size and morphology distribution according to the Asbestos International Association (AIA) for standardization analytical method for asbestos. The airborne asbestos fiber concentrations and its chemical composition of 92 personal samples were analyzed by phase contrast microscopy (PCM) and scanning electron microscope (SEM) equipped with an energy-dispersive X-ray analyzer (EDX). Personal monitoring of fiber levels demonstrated counts that ranged from 0.31 to 1.3 PCM f/ml (15.5-51.5 SEM f/ml). Geometric means of the asbestos concentrations were 1.3 PCM f/ml (51.5 SEM f/ml) and 0.86 PCM f/ml (42.1 SEM f/ml) according to the brake weighting and mixing and clutch mixing process, respectively. The geometrical mean concentrations were 0.63 PCM f/ml (31 SEM f/ml), which is considerably higher than threshold limit value (TLV) of the American Conference of Governmental Industrial Hygienists (ACGIH) which is 0.1f/ml. The SEM data demonstrate that the fibrous particles consisted, approximately, of chrysotile (50%), tremolite (30%), and actinolite (20%). Based on these findings, the 50% of airborne fibers inhaled by the workers were amphiboles asbestos with fibers equal and greater than 5 microm in length and 0.2 microm in diameter, and thus not included in the PCM-based fiber counts. Therefore, it might be expected that workers who worked in the brake and clutch manufacture will suffer from negative health effects of exposing to the amphibole asbestos fibers.

The effect of work-related and socio-demographic factors on Work Ability Index (WAI) among Iranian workers.

BACKGROUND: The Work Ability Index (WAI) is a suitable and valid instrument, which provides a general view of workers' abilities and functional capacities. OBJECTIVE: This study aimed to evaluate the effect of work-related and sociodemographic factors on work ability among employees of a company in Iran. METHODS: This cross-sectional study was conducted on 167 employees. Work ability was measured by the Persian version of WAI. A questionnaire was also developed to assess work-related and sociodemographic factors. The data were analyzed using univariate analysis of variance (ANOVA), independent t-test, and Pearson's correlation. RESULTS: The mean (SD) score of WAI was 38.4 (6.4). WAI mean score (p < 0.05) was associated with age, gender, sleep quality, smoking, work schedule, the conflict between the work and individual, family, and social lives, work injuries, and job satisfaction. CONCLUSIONS: To improve the workers' work ability, interventional programs should be concentrated on changing work schedules, improving sleep quality, limiting work hours, and not scheduling sensitive individuals to night shifts, those whose circadian rhythm stability and circadian rhythm amplitude is rigid type and languid type, respectively.

Low cost ergonomic interventions to reduce risk factors for work related musculoskeletal disorders during dairy farming.

BACKGROUND: Workers engaged in dairy farming are exposed to awkward and poor postures that may result in work-related musculoskeletal disorders (WMSDs). OBJECTIVE: This study carried out ergonomic interventions in order to eliminate and reduce awkward postures in dairy farming. METHODS: This quasi-experimental study applied rapid entire body assessments (REBA) to evaluate the risks associated with each posture while performing the assigned tasks on a dairy farm in Iran to identify high and very high-risk tasks. A participatory ergonomics model was used that incorporated suggestions by dairy workers to design the used interventions. RESULTS: In the first intervention, by using an automatic transmission system for pouring milk, one high and one very high-risk task- pouring milk into a bucket and pouring milk from a bucket into a tank, respectively- were eliminated. In the second intervention, two high-risk tasks- filling corn containers and pouring corn into the milling machine- were eliminated by using a material conveying vacuum pump to transfer corn from the ground to the opening of the milling machine. In the third intervention, a simple and cheap holding device for the bag was designed to reduce the posture risk score from very high to medium. The fourth intervention involved the use of a shovel with a handle appropriate to the anthropometric characteristics of the workers that reduced the posture risk from very high to medium. CONCLUSIONS: The results indicated that applying participatory ergonomic principles along with low cost and simple designs with high performance resulted in significant reductions in postural risks pertaining to of musculoskeletal disorders on Iran dairy farms.

Risk Factors for Developing Work-Related Musculoskeletal Disorders during Dairy Farming.

BACKGROUND: Dairy farming work involves frequent use of poor postures. These postures may increase the risk of developing musculoskeletal disorders among dairy workers. OBJECTIVE: To assess postural load during performance of various tasks related to dairy farming. METHODS: This cross-sectional study was conducted on a dairy farm in Iran. In order to assess postural load, tasks related to dairy farming were divided into 3 categories: feeding, milking, and manure disposal. Each task was then divided into its constituent work subdivisions (tasks). Finally, the working posture for each work subdivision was evaluated using Rapid Entire Body Assessment (REBA). RESULTS: Based on the results from the REBA score, the poorest risk scores (risk level 4) were associated with the following tasks: (1) manure disposal, (2) filling feed bags, and (3) pouring milk into a bucket. Other tasks such as filling corn containers, pouring corn into the milling machine, preparing the feed, pouring food into mangers, attaching the milking machine, and pouring milk from a bucket into a tank imposed high risk (risk level 3). The risk for the tasks of washing and disinfecting the udders were assessed as medium risks. CONCLUSION: The risk levels associated with most of the tasks on the studied farm were unacceptably high. Therefore, it is essential to implement ergonomic interventions to reduce risk levels of the tasks.

Study of the Continuous Improvement Trend for Health, Safety and Environmental Indicators, after Establishment of Integrated Management System (IMS) in a Pharmaceutical Industry in Iran.

BACKGROUND: Nowadays, organizations try to improve their services and consequently adopt management systems and standards which have become key parts in various industries. One of these management systems which have been noticed in the recent years is Integrated Management System that is the combination of quality, health, safety and environment management systems. AIM: This study was conducted with the aim of evaluating the improvement trend after establishment of integrated management system for health, safety and environment indicators, in a pharmaceutical industry in Iran. MATERIALS AND METHODS: First, during several inspections in different parts of the industry, indicators that should have been noted were listed and then these indicators were organized in 3 domains of health, safety and environment in the form of a questionnaire that followed Likert method of scaling. Also, the weight of each index was resulted from averaging out of 30 managers and the viewpoints of the related experts in the field. Moreover, by checking the documents and evidence of different years (5 contemplation years of this study), the score of each indicator was determined by multiplying the weight and score of the indices and were finally analysed. RESULTS: Over 5 years, scores of health scope indicators, increased from 161.99 to 202.23. Score in the first year after applying the integrated management system establishment was 172.37 in safety part and in the final year increased to 197.57. The changes of environmental scope rates, from the beginning of the program up to the last year increased from 49.24 to 64.27. CONCLUSION: Integrated management systems help organizations to improve programs to achieve their objectives. Although in this study all trends of health, safety and environmental indicator changes were positive, but at the same time showed to be slow. So, one can suggest that the result of an annual evaluation should be applied in planning future activities for the years ahead.

Evaluation of asbestos exposure during brake repair and replacement.

Occupational exposure to asbestos fiber of brake repair job (auto mechanics) has seldom been evaluated in Iran. Accordingly, we evaluated asbestos fiber concentrations in the breathing zone of auto mechanics between July 2008 and December 2008. The asbestos fiber concentrations of 60 personal air samples collected from 30 cars and trucks brake replacement and they were analyzed by phase-contrast optical microscopy (PCM) and scanning electron microscopy (SEM) by energy-dispersive X-ray analysis. The geometric means of the personal monitoring fiber concentrations were 0.92 PCM f/ml and 0.46 PCM f/ml respectively in car and passenger heavy truck auto shops. There was a significant differences in the asbestos fiber concentrations between the car and truck auto shops (p=0.006). Based on these findings, auto mechanics who worked with asbestos containing brake may have been exposed to asbestos concentrations approximately 7 times higher than the current occupational safety and health agency (OSHA) permissible exposure limit (PEL) of 0.1 f/ml. Fiber morphology and energy dispersive X-ray analysis by SEM revealed that amphibole fibers such as tremolite and actinolite existed in the brakes dust and that the vast majority (>30%) of the airborne chrysotile fibers were greater than 1 µm in diameter. It can be concluded that the imported chrysotile asbestos contains trace amounts of tremolite and actinolite fibers and they are responsible for the high airborne asbestos levels and occupational exposure to amphibole asbestos in auto mechanics job in Iran. Thus, it is to be expected that the auto mechanics will suffer negative health effects due to exposure to the serpentine and amphibole asbestos fibers.