Musculoskeletal Problems amongWorkers of an Iranian Rubber Factory: Alireza CHOOBINEH, et al. Occupational Health Department, School of Health, Shiraz University of Medical Sciences, Iran-Musculoskeletal disorders (MSDs) are a common health problem throughout the world and a major cause of disability among the work force. Assessment of exposure level to MSD risk factors can be an appropriate base for planning and implementing interventional ergonomic programs in the workplace. This study was conducted among workers of an Iranian rubber factory with the objectives of (a) determination of the prevalence of MSDs among production line workers, and (b) assessment of the level of exposure to MSD risks. In this study, all 16 production units of the factory were studied. In each unit, 50% of the workers were randomly selected and included in the study. A total of 454 workers participated. The Nordic Musculoskeletal Questionnaire was used to study the prevalence of MSDs and the Quick Exposure Check (QEC) technique was applied to assess physical exposure to the risks. The videotaping technique was used to collect the required data for each worker. The vast majority of the workers (73.6%) had suffered from some kind of musculoskeletal symptoms during the last 12 months. The highest prevalence was reported in the lower back (50.2%), knees (48.5%) and upper back (38.1%). In 85.5% of the workers studied, the QEC score was high or very high. Statistical analysis showed a significant association between the QEC level of risk and MSDs symptoms (p<0.001). The most common ergonomics problems were found to be awkward postures and manual material handling. MSDs had occurred with a high rate among workers of this rubber factory. Corrective measures for reducing risk level seemed essential. Elimination of awkward postures
Field Studyand manual material handling in the workplace were recommended. (J Occup Health 2007; 49: 418-423)
Diazinon (DZN) is an organophosphate pesticide widely used in agricultural to control insects and in veterinary medicine to control ectoparasites. This study investigated the induction of oxidative stress in the brain, heart, and spleen of Wistar and Norway rats treated with acute doses of DZN. Female Wistar and Norway rats were treated with 25, 50, 100, and 200 mg/kg of DZN by intraperitoneal injection. The animals were sacrificed 24 h after treatment, and tissues were isolated and analyzed. The result of this study shows that DZN at higher doses increased the level of malondialdehyde, superoxide dismutase and glutathione S-transferase activities and decreased glutathione (GSH) level, lactate dehydrogenase, and cholinesterase activities in the brain, heart, and spleen of both rat strains. At these concentrations, DZN toxicity also lead to a significant decrease in catalase (CAT) activity in all tissues of Wistar rat and brain of Norway rat, while it increased heart CAT activity in Norway rat. However, the alteration of these parameters was observed at lower doses of DZN in Wistar rat. These results suggest that DZN at higher doses induces the production of free radicals and oxidative stress in rat tissues and strains by alteration of antioxidant enzyme activity, depletion of GSH, and increasing lipid peroxidation. Induction of oxidative stress in DZN-treated rats is in the order of brain > heart > spleen. Wistar rats appear to be more sensitive to the effects of DZN on oxidative stress induction compared to Norway rat.
Introduction:The present research aimed to examine Visual Working Memory (VWM) test scores, as well as hormonal, genomic, and brain anatomic changes in the male rhesus macaques exposed to Extremely Low Frequency Magnetic Field (ELF-MF).Methods:Four monkeys were exposed to two different ELF-MF frequencies: 1 Hz (control) and 12 Hz (experiment) with 0.7 μT (magnitude) 4 h/d for 30 consecutive days. Before and after the exposure, VWM test was conducted using a coated devise on a movable stand. About 10 mL of the animals’ blood was obtained from their femoral vain and used to evaluate their melatonin concentration. Blood lymphocytes were used for assaying the expressions of N-Methyl-D-aspartate NMDA-receptor genes expression before and after ELF exposure. Anatomical changes of hippocampus size were also assessed using MRI images.Results:Results indicated that VWM scores in primates exposed to 12 Hz frequency ELF increased significantly. Plasma melatonin level was also increased in these animals. However, these variables did not change in the animals exposed to 1 Hz ELF. At last, expression of the NMDA receptors increased at exposure to 12 Hz frequency. However, hippocampal volume did not increase significantly in the animals exposed to both frequencies.Conclusion:In short, these results indicate that ELF (12 Hz) may have a beneficial value for memory enhancement (indicated by the increase in VWM scores). This may be due to an increase in plasma melatonin and or expression of NMDA glutamate receptors. However, direct involvement of the hippocampus in this process needs more research.
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