International Journal of Occupational Hygiene
Volume:2 Issue: 2, Jul 2010

Exposure to vibration is the cause of some occupational injuries and diseases. Objective of this study was determination of vibration exposure of tractor drivers and assessment of musculoskeletal disorder. This cross-sectional and descriptive- analytical study was administrated to 95 tractor drivers to census method and measuring induced vibration to the drivers was done in three axis, x, y, and z in tractors with load (10000 liter water), without load, with 10 km/h speed, by the vibration meter instrument “Sevantek”. The information related to musculoskeletal disorder was collected by using Nordic questionnaire. Data from both parts was analyzed by using SPSS. In the over load tractor group and with velocity vibration 10km/h, 50% of workers were in the range of reduced comfort boundary, 39.3% in the range of fatigue decreased proficiency boundary and 10.7% in over exposure limit. This results were in the without load tractor group and with the same velocity, 23.8% of people were in the range of reduced comfort boundary, 42.9% in the range of fatigue decreased proficiency boundary and 33.3% in the range of over exposure limit and waist with 56.8% had the greatest rate of pain and ankle with 9.5% had the least amount of pain rate. Using of many tractors in city to displace water and other applications, paying attention to the health of drivers and checking the periodically, is needed.

This study describes the synthesis of molecularly imprinted polymers (MIPs) by using an Anti-ChE OPs, namely dursban, as a template. Non-covalent bulk polymerization was successfully applied to synthesis different imprinted and non-imprinted polymers with MAA, MMA, AA, and 4-vpy as monomer in selected porogens (chloroform, toluene, and acetonitrile). In order to evaluate the template binding of the polymers, equilibrium binding experiments was carried out. High binding amount of imprinted polymers compared to non-imprinted polymer was due to effective imprinting or encoding of dursban template shape in the polymer matrixes. From this study, the dursban imprinted polymers prepared using acidic MAA as a functional monomer showed excellent molecular binding ability for dursban. This is because the hydrogen binding interaction between dursban and MAA may be formed between sulfur, oxygen, chlorine, and nitrogen groups of dursban and carboxyl group of MAA. The results shows the use of chloroform as porogen, with a poor hydrogen binding power, significantly affects the binding extend of the MIPs. MAA and chloroform were found to be the most suitable monomer and porogen for the preparation of appropriate dursban molecularly imprinted polymers. This study has shown the possibility of synthesizing and using molecularly imprinted polymers as sorbent for an Anti-ChE OPs.

Since individuals spend the majority of their times indoors, fine particles generated in indoor combustion processes and by resuspension are important for health effects assessment. The nature and magnitude of indoor particle exposures can change rapidly because of the rapid changes in activities and sources. Indoor PM2.5 concentrations were measured in indoor office, café, and home where people spend majority of their time in there. A real time monitor was used to provide a high degree of resolution for investigating temporal patterns in particle concentrations. The average PM2.5 concentration obtained from the direct reading compared with the mean PM2.5 concentrations that are obtained by gravimetric measurements during the same continuous sampling. Mean PM2.5 concentrations in the big office were more than twice as high as those measured in the small quiet office (19.8 and 7.3 respectively). In the home, cooking increased PM2.5 concentration. The highest particle concentrations in home (average 28 µg m-3) were related to a period around midnight when there were a larger number of occupants inside the living room. Mean PM2.5 concentrations measured in the smoking area of the café were much higher than those measured in the non-smoking area (50.0 and 17.6 µg m-3 respectively). Outdoor air pollution can affect the indoor particulate concentration when the indoor source not exists. Smoking, cooking, and resuspension of indoor particulate matter are the most important sources for indoor particle concentrations.=

Proposing a Noise Standards should be considered seriously by the governmental authorities because of the prevalence of hazardous noise exposure and the seriousness of the effects. In a survey founded by World Health Organization’s regional office in Iran, the existing as well as gathered data from field were applied to propose a National Occupational Noise Exposure Limit. The collected data plus the existing data were processed to: propose a national occupational noise exposure limit and depict the major restrictions in application of existing field data in proposing a national occupational noise exposure limit.Results obtained from the present study shows that the occupational noise levels of 90 to 95 dBA can lead to hearing losses greater than 25 dBA. It was shown that occupational noise levels of 85 to 90 dBA would not lead to hearing losses greater than 20 dBA. The comparison of hearing losses shows that the noise levels of less than 80 dBA will not lead to any significant hearing loss. It was deduced that 85 dBA can be recommended for a national occupational noise limit in Iran. The study also showed that the application of existing field data to recommend a national occupational noise standard may have some restrictions.

The aim of the present study was to examine the rate of noise induced hearing loss in a group of punching and cutting section and other occupational groups workers and its relation with sound pressure levels, age and work history. This descriptive, cross-sectional study included 245 workers of the punching and cutting section and other occupational groups of an Iranian Axial Parts Factory in 2009. Hearing threshold limits were measured in both ears at 250, 500, 1000, 2000, 40000 and 8000 Hz with AC40 clinical Audiometer. In addition, sound pressure levels measured with IEC 60651 sound level meter at dBA in 148 stations of workers task with NIOSH standard method. At places where the sound pressure levels were upper than 85 dBA, the frequency analysis was also done. The mean age of the population under study was 34.61 8.76 years and mean work history was 11.74 4.21 years. Equivalent sound level (Leq) was at least 98.1dBA and at the most 115.7dBA. In addition, result indicated NIHLt was ranged 17.45 to 56/67 dB. According to regression analysis, with assumption of a fixed work history, there is a mean decrease of 0.21 dB in NIHLt for every decibels of increase in equivalent sound level (Leq) and with assumption of a fixed equivalent sound level (Leq); there is a mean decrease of 0.42 dB in NIHLt for every year of increase in work history (p < 0.05). NIHL of varying degrees in workers of an Iranian Axial Parts Factory starts at 4000 Hz and is then directed towards upper or lower frequencies.

The present study aimed at assessing cement dust exposure and its relationship to lung function at a Portland cement factory in Ilam, Iran. Lung function tests were carried out on 112 workers at the cement factory in 2008-09. Simultaneously 85 non exposed workers were used as control. Lung function tests were performed for all subjects. Additionally, total dust level was determined by the gravimetric method. Moreover, X-ray diffraction (XRD) technique was performed to determine the SiO2 contents of the bulk samples. The arithmetic means (AM) of personal total dust were higher in the crusher (27.49 mg/m3), packing (16.90 mg/m3), kiln (15.60 mg/m3), cement mill (13.07 mg/m3), raw mill (10.31 mg /m3) than in the maintenance (3.14 mg /m3), and administration (1.55 mg/m3). The geometrical mean (GM) concentration was 12.12 mg/m3, which were considerably higher than occupational exposure limit (OEL) of the American Conference of Governmental Industrial Hygienists (ACGIH), which is 10 mg/m3. Based on the results, the probability of the long-term mean exposure exceeding to the OEL of 10 mg/m3 for total dust were higher in the kiln (100%), packing (100%), cement mill (90%), crusher (73%), raw mill (60%) than in the maintenance (0%), and administration (2.3%). Ventiliatory function evaluation, as measured by the function parameters, showed that 35.7% of the exposed workers had abnormality in lung function compared with 5.7% of those unexposed. Statistical analysis of the data indicated that exposed workers compared to the unexposed groups showed significant reductions in Forced Expiratory Volume in one second percent (FEV1), Forced Vital Capacity (FVC), and FEV1/FVC (p< 0.05).

Large urban areas are facing growing problems of noise pollutions. Geospatial Information Systems (GIS) can conveniently be adapted to gather, analyze and present noise information. GIS can also be extended to answer to user specific problems through deterministic and statistics models. The objectives of this research were to measure urban traffic noise levels, analyze temporal and spatial dynamics of urban traffic-induced noise pollution in the first districted of Tehran estimate the noise for pollution concentration, assess the results of Federal Highway Administration Traffic Noise Model (FHWA-TNM) and Iranian Traffic Noise Predictor (ITNP); and represent them in a GIS environment. Measurements were done at the traffic peak time and also when the traffic was at its minimum, during three successive months. In this study, Leq, L10, L50, L90, Lmax and Lmin were gathered. The results demonstrated that most of commercial and residential regions surrounding the main streets are suffering from sever noise pollution. Processed data, spatial analysis and models are integrated within the framework of ArcGIS software environment, providing adequate tools to address noise issues. The assessment showed that the issue of noise pollution is currently ignored in urban regulations concerning environmental quality.

Nowadays, occupational accidents are one of the most important problems in developing countries. Job stress and unsafe acts have been also recognized as effective factors in increasing the risk of occupational accidents. The main goal of this research was to evaluate the relationship between job stress and unsafe acts with occupational accidents. This study was performed on 195 employees in Pars Khodro industry in 2007. Safety behavior sampling technique and standardized job stress questionnaire were used in current research. The information was then analyzed using SPSS and statistic tests. According to findings of job stress questionnaire 88 percent of workers were at level of high stress. Accidents at work were associated with job stress and unsafe acts. There was also a significant relationship between job stress and unsafe acts (p< 0.05). The regression logistic test showed that 1% increase in the rate of unsafe practice had a higher impact on the number of accidents than a 1% increase in job-related stress. Therefore, based on the degree of change in these two variables, it is possible to predict the number of accidents in an organization. Reducing or eliminating identified effective stress factors and decreasing unsafe acts have been suggested to control the consequences of accidents. To achieve this, implementing behavior based safety principles can be an effective measure.