The role of oxidative stress in pulmonary function in bakers exposed to flour dust.

Objective. This study aimed to determine the effect of exposure to flour dust on pulmonary function and the role of oxidative stress. Methods. This case-control study was conducted on 163 bakery workers (exposed group) and 177 administrative workers (unexposed group). Pulmonary function and flour dust exposure were measured by spirometry and NIOSH 0500 and 0600 methods. Oxidative stress indices including malondialdehyde (MDA), nitric oxide (NO) and total antioxidant capacity (TAC) were measured in serum samples. Results. The mean respirable and total dust exposure of bakery workers were 2.5 ± 1.72 and 6.53 ± 3.26 mg/m3. The forced vital capacity (FVC) and forced expiratory volume in the first 1 s (FEV1) were significantly lower in the exposed group than in the unexposed group. The levels of MDA and NO were higher in smokers than in non-smokers in the exposed group. The most important variables that predicted FVC and FEV1 were MDA, NO and TAC. With increased exposure to respirable dust, the levels of MDA (ß = 3.39, p < 0.001) and NO (ß = 16.48, p < 0.001) increased and total antioxidant levels decreased (ß = -0.37, p < 0.001). Conclusions. Exposure to flour dust may impair pulmonary function by increasing oxidative stress and weakening antioxidant defense.

Influences of Occupational Burnout and Personality on Lipid Peroxidation Among Nurses in Shahroud City, Iran.

Considering the relationship between occupational burnout and oxidative stress, identifying the factors that affect occupational burnout, such as recognizing individual characteristics, would be beneficial for implementing strategies to reduce oxidative stress levels. This study was conducted on 92 nurses from a hospital in Shahroud, a city in northeastern Iran, who were chosen at random. The data was collected through the Demographic Questionnaire, Maslach Burnout Inventory and Personality Factors Inventory. Each participant's serum markers of oxidative stress were also measured. Total antioxidant capacity (TAC) and neuroticism were found to have a negative relationship in this study. Furthermore, marital status, the ward where nurses work, the type of contract, emotional exhaustion, and depersonalization were all found to be significant predictors of malondialdehyde (MDA). Neuroticism, emotional exhaustion, and depersonalization were the most important predictors of oxidative stress levels.The results of this study suggest that some approaches to reducing oxidative stress can be implemented by identifying the factors influencing occupational burnout and also by recognizing individuals' personality traits.

Understanding the role of oxidative stress in the incidence of metabolic syndrome and obstructive sleep apnea.

BACKGROUND: Understanding the causes and risk factors of metabolic syndrome is important for promoting population health. Oxidative stress has been associated with metabolic syndrome, and also obstructive sleep apnea. These are two diseases which have common prognostic characteristics for heart disease. The aim of this study was to examine the role of oxidative stress in the concurrent presence of metabolic syndrome and obstructive sleep apnea in a working population. METHODS: Participants were 163 artisan bakers in Shahroud, Iran, routinely exposed to significant heat stress and other oxidative stress indicators on a daily basis as part of their work. Using a cross-sectional design, data relevant to determining metabolic syndrome status according to International Diabetes Federation criteria, and the presence of obstructive sleep apnea according to the STOP-Bang score, was collected. Analyses included hierarchical binary logistic regression to yield predictors of the two diseases. RESULTS: Hierarchical binary logistic regression showed that oxidative stress - alongside obesity, no regular exercise, and smoking - was an independent predictor of metabolic syndrome, but not obstructive sleep apnea. Participants who were obese were 28 times more likely to have metabolic syndrome (OR 28.59, 95% CI 4.91-63.02) and 44 times more likely to have obstructive sleep apnea (OR 44.48, 95% CI 4.91-403.28). Participants meeting metabolic syndrome criteria had significantly higher levels of malondialdehyde (p <  0.05) than those who did not. No difference in oxidative stress index levels were found according to obstructive sleep apnea status. CONCLUSIONS: Our findings suggest that oxidative stress contributes to the onset of metabolic syndrome, and that obstructive sleep apnea is involved in oxidative stress. Whilst obesity, exercise, and smoking remain important targets for reducing the incidence of metabolic syndrome and obstructive sleep apnea, policies to control risks of prolonged exposure to oxidative stress are also relevant in occupations where such environmental conditions exist.

Investigating the effects of vitamins E and C on oxidative stress and hematological parameters among power plant workers: A double-blind randomized controlled clinical trial.

The present study aimed to determine the effect of taking antioxidant vitamins including vitamins E and C in reducing oxidative stress levels and improving blood parameters. This double-blind randomized controlled trial study was conducted among the employees working in different parts of a power plant in Semnan, Iran, in 2017. A total of 91 employees were randomly allocated to four groups including vitamin E (400 units per day), vitamin C (1000 mg per day), vitamin E + C for 90 days, and control. The levels of malondialdehyde (MDA), superoxide dismutase (SOD), catalase (Cat), and total antioxidant capacity (TAC) in plasma, and hematological parameters were measured in the participants before and after the intervention. A significant increase was seen in the mean level of SOD, Cat, and TAC in the vitamin-treated groups as well as a significant decrease in mean MOD in vitamin C and vitamin E groups after the intervention. In the intervention groups, the number of red blood cells, hematocrit, and the level of mean corpuscular hemoglobin (MCH) and MCH concentration significantly increased. After the intervention, the mean levels of MDA, SOD, and Cat in vitamin E group were significantly lower than the control group. The mean level of TAC decreased only in the vitamin C group compared to the control group. Taking vitamins E and C as nonenzymatic scavengers of free radicals appears to decrease lipid peroxidation and increase the level of antioxidant enzymes, which can be imbalanced by exposure to extremely low-frequency electromagnetic fields in power plant employees. Furthermore, some hematological parameters can be improved by consuming these vitamins.

The effect of heat stress on hematological parameters and oxidative stress among bakery workers.

Heat stress causes physiological changes, and changes in hematological parameters and hormonal levels in the human body, known as thermal strain. This study was conducted to determine the effect of exposure to heat stress on hematological parameters and oxidative stress in the bakers of Shahroud City, Iran. A total of 163 bakery workers (exposed group) and 135 office workers (unexposed group) with a minimum of 1-year working experience were selected. Exposure to heat stress was measured using ISO-7243 criteria on the hottest days of the year (late July and August). Wet-bulb globe temperature (WBGT) was calculated based on indoor environments. Oxidative stress indices including malondialdehyde (MDA), nitric oxide (NO), total antioxidant capacity (TAC) in the bakers' and office workers' serum and hematological parameters were measured. Statistical analysis was done through independent t-test, and multivariate linear regression using SPSS v24. Analysis of hematological parameters showed that about 70% and 68% of the bakers had abnormal mean cell volume (MCV) and white blood cell (WBC) count, respectively, while only around 12% of them had abnormal mean cell hemoglobin concentration (MCHC). The counts of red blood cells (RBC), WBC, lymphocytes (LYM), and MCV showed significant differences in different occupational groups (p < 0.05). The levels of MDA and NO were significantly higher in bakers with WBGT more than the threshold value (p < 0.05). The WBGT index for assessing heat stress can be used as a predictor variable for MDA and NO levels. In addition, heat stress exposure could be a risk factor for abnormal WBC, RBC, LYM, and MCV.

Effect of long-term occupational exposure to extremely low-frequency electromagnetic fields on proinflammatory cytokine and hematological parameters.

Purpose: The present study aimed to investigate the effect of extremely low-frequency electromagnetic fields (ELF-EMFs) on proinflammatory cytokines and hematological parameters, among the employees of a power plant, which are one of the most important occupational groups exposed to ELF-EMFs extensively.Materials and methods: The studied population included 112 employees of a power plant as the exposed group and 138 unexposed employees who were enrolled based on inclusion and exclusion criteria. The magnetic flux density and the strength of the electric field were determined by spot measurements and according to the IEEE C95.3.1 standard. Proinflammatory cytokines including serum interleukin-1ß (IL-1ß), interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α); and hematologic parameters of all subjects were measured.Results: The mean level of IL-1ß and IL-6, white blood cell count (WBC) and red blood cell count (RBC), lymphocyte percentage (Lym%), mean corpuscular volume (MCV), platelet count (PLT) and procalcitonin (PCT) were significantly more in the exposed group, than the unexposed group. The mean serum levels of IL-6, IL-1ß and some of the hematological parameters including WBC, lymphocyte, RBC and hematocrit were higher in technicians which had the highest level of exposure to magnetic fields compared to other groups and these relations were linear.Conclusions: Long-term exposure to ELF-EMFs probably affects immune responses, by stimulating the production of proinflammatory cytokines, and increasing some hematological parameters.

The Effect of Extremely Low-Frequency Electromagnetic Fields on the Prevalence of Musculoskeletal Disorders and the Role of Oxidative Stress.

Extremely low-frequency electromagnetic fields (ELF-EMFs) may cause negative health effects. This study aimed to investigate the direct and indirect effects of chronic exposure to extremely low-frequency electric and magnetic fields on the prevalence of musculoskeletal disorders (MSDs). In this cross-sectional study, 152 power plant workers were enrolled. The exposure level of employees was measured based on the IEEE Std C95.3.1 standard. Superoxide dismutase (SOD), catalase (Cat), glutathione peroxidase (GPx), total antioxidant capacity (TAC), and malondialdehyde (MDA) (independent variables) were measured in the serum of subjects. The Nordic musculoskeletal questionnaire was used to assess MSDs (dependent variable). The mean exposure of electric and magnetic fields were 4.09 V/m (standard deviation [SD] = 4.08) and 16.27 µT (SD = 22.99), respectively. Increased levels of SOD, Cat, GPx, and MDA had a direct significant relation with MSDs. In the logistic regression model, SOD (odds ratio [OR] = 0.952, P = 0.026), GPx (OR = 0.991, P = 0.048), and MDA (OR = 0.741, P = 0.021) were significant predictors of MSDs. ELF-EMFs were not related to MSDs directly; however, increased levels of oxidative stress may cause MSDs. Bioelectromagnetics. 2019;40:354-360. © 2019 Bioelectromagnetics Society.

Effects of patient-handling and individual factors on the prevalence of low back pain among nursing personnel.

BACKGROUND: Patient-handling is one of the main tasks of nursing personnel; it imposes compressive and shear forces on nurses' lower spine. The aim of this study was to determine the prevalence of Low Back Pain (LBP), risk factors in the incidence of such disorders, and patient handling risk assessment among nursing personnel. METHODS: This study was carried out on 243 randomly selected nursing personnel who played a role in handling the patients (58 wards). Patient Transfer Assessment Instrument (PTAI) checklists alongside Standardized Nordic Musculoskeletal Questionnaires (NMQ) were used for data collection. The statistical analyses such as independent t-test and Chi-Square test were used. RESULTS: Prevalence of LBP among nursing personal was 69.5% in the previous 12 months. Significant correlations were found among age, working hours per week, work experience, BMI, gender and shift-work. Results of PTAI index assessment revealed that more than 90% of subjects were in medium and severe risks of LBP. PTAI index scores were significantly associated with LBP (P < 0.05). CONCLUSION: PTAI index is regarded as an efficient tool for risk level classifications and identification of effective factors on LBP incidence among nursing personnel involved in patient transfer. In this regard and for the aim of ergonomic intervention towards the reduction of LBP incidence among nurses, the modification of improper factors which are identified in PTAI index such as the use of advanced patient handling equipment, increase in work posture guidance and work arrangements, can be mentioned.