Nickel is widely used in many industries. It is known as an immunotoxic, neurotoxic, pulmonary toxic, nephrotoxic, hepatotoxic, and carcinogenic agent. Biological monitoring is a useful tool to assess the internal exposure to toxic compounds. Because of trace concentration of analytes in biological samples and matrix interferences, the preparation of such complicated samples is necessary prior to analysis. This study aimed to optimize the parameters affecting solid phase extraction (SPE) procedure and compare the enrichment recoveries of sorbents XAD-7 and chromosorb 105 for preconcentration and separation of nickel in urine, hair and nail samples. Solid phase extraction using both resins was optimized regarding the sample pH, ligand concentration, loading flow rate, elution solvent, sample volume, elution volume, amount of resins, and matrix interferences. The optimized procedure was validated based on the "within-day" and "day-to-day" reproducibility experiments. The proposed method was applied for pre-treatment of urine, hair and nail samples. Nickel was extracted with recoveries in the range of 94-100%. A good reproducibility and repeatability was obtained for optimized method using both resins under the existing conditions. The concentration of nickel in workers’ biological samples was determined using two sorbents. There was no significant difference between obtained recoveries for XAD-7 and chromosorb 105. This optimized method can be successful in simplifying sample preparation for trace residue analysis of Ni in different matrices for evaluation of occupational and environmental exposures. Resin XAD-7 is recommended for next experiments because of its lower cost and simpler preconditioning compared to chromosorb 105.

Healthy hire effect (HHE) is considered as an epidemiological phenomenon, complicating the assessment of a true cause - effect relationship between occupational exposure and health status of workers. The current study was aimed at identification and elimination of HHE in the risk assessment of arterial hypertension (AH) in coal miners. Overall, 1553 miners, working in West Siberia, were enrolled in the cross-sectional cohort study of risks for AH, the control group included 2266 subjects from ther industrial sectors. The HHE identification was carried out with RR values in the age groups. A method of HHE elimination designed with analytical age-adjustment of hypertension rate in the studied group with the subsequent recalculation of the RR was implemented and tested. Initial data suggested a low risk of hypertension development in coal miners (RR = 0.58, 95 % CI 0,53:0,64) compared to workers of other industrial sectors. Elimination of HHE resulted in an increase of risk for hypertension in coal miners (RR = 1.11, 95 % CI 1,04:1,19). HHE reports that the health status of subjects, employed in the coal industry sector, is better compared to the other working population, resulting in lower incidence of hypertension. The application of the HHE elimination method resulted in the opposite results of professional affiliation impact on the incidence of hypertension compared to the initial data.

This study aimed to evaluate the radiation safety condition and the level of radiation-awareness amongst staff and patients in 18 hospitals of Shahid Beheshti University of Medical Sciences, Tehran, Iran. This descriptive, cross–sectional study was administered to patients and personnel, also making a review on the radiation-safety status in the hospitals. In evaluating the level of awareness, 218 patients and 173 staff took part in the survey. A12-question inventory was used for evaluating radiation-safety status. In addition, 2 questionnaires including 15 and 6 questions were used in order to evaluate the level of radiation awareness among staffs and patients respectively. The questionnaires used included personal and general questions and its validity and reliability had been confirmed (Cronbach's alpha=0.711). The results have shown 71.1% good radiation-safety awareness among staff. Moreover, the level of staff awareness was not associated with educational level, gender, field of study, age and job experience. Conversely, only 6% of the patients have shown a good awareness level. In addition, as it depicted by the results there was a significant relation between awareness level and age (P<0.017), job (p<0.000) and educational level (p<0.004). Furthermore, the radiation safety status in 5 medical nuclear center and 18 radiology facility was 70% and 74%, in turn.  Unfortunately, radiation safety awareness is generally inadequate among radiologists and particularly poor in patients. The authors firmly recommend that patients should have more practical training and information available in this context.

Severe accidents of process industries in Iran have increased significantly in recent decade. This study quantitatively analyzes the hazards of severe accidents imposed on people, equipment and building by a hydrogen production facility. A hazard identification method was applied. Then a consequence simulation was carried out using PHAST 6.54 software package and at the end, consequence evaluation was carried out based on the best-known and different criteria. Most hazardous jet fire and flash fire will be occurred in desulfurization and reformer units respectively. The most dangerous vapor cloud explosion will be caused by a rupture in desorfurizing reactor. This incident with an overpressure of 0.83 bars at a distance of 45 m will kill all people and will destroy all buildings and equipments that are located at this distance. The safety distance determined by TNO Multi-Energy model and according to the worst consequence is equal to 260 m. Vapor cloud explosion will have the longest harmful distance on both human and equipment compared to jet fire and flash fire. Atmospheric condition will have a significant influence on harmful distance, especially in vapor cloud explosion. Therefore, the hydrogen production by natural  gas  reforming  is  a  high-risk  process  and  should  always  be  accompanied  by  the  full implementation of the safety rules, personal protection and equipment fireproofing and building blast proofing against jet fire and explosions.

Well-designed lighting decreases accidents and diseases of eyes and can increase productivity and concentration. Increase of energy price and a high proportion of electric lighting energy consumption in buildings due to defects in designing and maintenance led to desirable lighting to be reduced. One of our challenges in providing health and quality of lighting is lack of economic justification of projects. Furthermore, evaluating the lighting systems is very important to improve these systems and maintaining lighting quality. In this study the performance of the various lighting systems has been evaluated. The health and quality conditions of lighting systems, energy loss and the difference between the lighting variables, based on room index and the designed required levels (normalized power density) in studied schools and education workrooms in Ahvaz Jundishapur University of Medical Sciences (south-west of Iran) have been evaluated. Results showed that the modern lighting systems had 58% more efficient than the traditional others. In other words, modern lighting systems increase illuminance to 58 percent without increasing the electrical energy power. The performance indices of lighting systems between workrooms that had modern systems and traditional was significant (p=0.000). In 77.4% of spaces of the school of Medicine, where that had new lighting systems, the satisfaction index of users was equal to one. Evaluation of lighting systems in order to decreasing the electrical energy power along with preserving the standards of illumination intensity is very important, and some appropriate solutions could be adopted by replacing the traditional systems with the new others.

Since the late 1990s, different web-based submission and peer review systems have emerged, and significant numbers of journals have shifted from their old paper-based systems to the web-based ones. Exploring the main features of these online systems might lead to better understand this flow. This study was performed to examine the features and capabilities of online submissions and peer review systems, with focus on the  author role,  which have been currently using by Iranian, approved medical and biomedical journals. This descriptive study was conducted during 2011-2012. The population of the study was peer review systems of approved medical and biomedical journals by Ministry of Health and Medical Education, Iran. In  this term, 199 journals were identified. Data were gathered by a standardized, researcher made checklist. The data were analyzed using SPSS 18 and Microsoft Excel 2007. 27 out of 199 journals were using no systems. 21 out of 199 were using 12 systems with inaccessible information or unknown status (which were removed from this study), and 151 journals were using 6 systems which were examined in this study. Evaluated systems were more than 80% in compliance with the research checklist. Due to rapid changes in information technology and information systems` designs, it is required for such systems to be constantly evaluated. It is of high value to investigate new demands of beneficiary groups like authors and researchers, editorial boards, and reviewers in this regard.

Carbon disulfide is used predominantly in the manufacture. It has affects the nervous system. In this study, the applicability of SPME as a passive sampler for determination of carbon disulphide in air was studied. Effect of sampler and environmental parameters on uptake of Carbon disulphide was studied as well. Four fibers were tested to select the best sampler for determine carbon disulfide in ambient air. A standard generation chamber was built in the laboratory and was used to test the SPME. Analysis SPME samples were carried out by a gas chromatography-Mass spectrometry and results were compared with data obtained with National Institute for Occupational Safety and Health (NIOSH) method 1600. Polymethylsiloxane-carboxen (PDMS/CAR) showed  the  most  effective stationary phase  material for sorbing BTEX among other materials (polyacrylate, PDMS, PDMS/divinylbenzene). Its linearity range in exposed mode was less than 10 minutes but with its retracted mode application, its linearity increased up to 8 hours. Temperature had not linear effect on uptake of pollutant in temperatures lower than 25, it has positive effect and above this range it has negative effect. Relative humidity had negative effect on mass loaded on fiber. Velocity in range of static to 0.5 m/s had no significant effect. The precision of the method was 4.18% relative standard deviation (RSD). The detection limit for carbon disulfide in the GC/MS system in SIM mode was 6.7 ng per sample. SPME is a good alternative for sampling of carbon disulfide in air. However, for the situations in high humidity values it should be used with care.

Heat stress particularly  at  outdoor  workplaces in hot-dry    climates can  disrupt    the physical or mental functions and effect negatively on human performance. We aimed to study the effect of heat stress on productivity loss among workers of brick workshops in Qom Province – central Iran. This cross-sectional descriptive and analytic study was performed on 184 workers in 40 brick workshops. Environmental parameters including dry temperature, natural wet-bulb temperature, globe temperature, relative humidity and air velocity were measured at three times during work shift. WBGT (Wet Bulb Globe Temperature) heat stress index was calculated based on equation provided by Australian Bureau of Meteorology. Potential  labor productivity losses due  to  heat  stress  were  determined using  a  graph presented already. The total average of WBGT was 31.84±3.46°C. WBGT index according to different jobs  was  39.48±8.2°C, 29.86±2.79°C, 29.31±0.97°C and  28.69±1.89°C for working in  kiln,  material handling,  working  on  conveyor and  making  adobe,  respectively.  The  average  loss  productivity  in mentioned tasks was 93.57±16.54, 66.58±20.58, 65.53±15.26 and 48.27±13.04 respectively, with total average of productivity loss 68.48±16.35%. The statistically significant relationships were found between WBGT values and percentage of loss productivity in total and for all understudy jobs (p<0.001). Heat stress can lead to decrease in labor productivity at outdoor workplaces like brick industries. According to climate change in the future and gradual global warming, paying more attention to the occupational health issues in outdoor workplaces at dry and warm environment seems to be more important than before.