جستجوی مقالات مرتبط با کلیدواژه "مواجهه ی شغلی" در نشریات گروه "پزشکی"

One of the major health issues in developed countries is the workplace air pollution. Cement factories are one of the industries where many workers worked in them. Workers in this industry are exposure with many harmful factors, such as ergonomics factor, physical factors, and in particular various chemical agents, during their job. The most important factors that threaten the health of workers in the cement industry are dust and respirable particles of cement. Respirable particles of cement contains some elements such as arsenic, calcium, aluminum, cadmium, lead, cobalt, zinc, iron, and chromium. Recent studies concluded that the concentrations of arsenic, chromium, lead, and cadmium within the particles are higher than the other metals. Exposure to heavy metals within cement respirable particles can lead to some adverse health effects among exposed workers. Expanding of industries and emission of respirable particles containing heavy metals in the workplace ambient causes higher exposure for workers within various industries and therefore has become a major problem in these industries, including the cement industry. To arrive the health goal that is protection of the workers, exposure to chemicals and the dangers of exposure to these substances need to be scrutinized. Risk assessment is defined as the process of assessing the risks arising from risks in the workplace by taking control measures and deciding whether or not to accept them. Risk assessment is a basic action for evaluation of danger in the workplace and the first step for risk management. Quantitative health risk assessment for different chemical agents in industries is necessary to decide on control of risk and management measures to reduce risk and determine risk level of these substances. This process combines scientific information about the toxic properties of chemicals as well as the results of chemical measurements in the workplace can provide comprehensive information on the measure of risk and how best to deal with these potential risks. The aim of this study was to assess the risk level of workers occupational exposure to heavy metals (lead, chromium, cadmium) within cement respirable particles for exposed workers in a cement factory.

This cross-sectional study was conducted in one of the cement industries during warm  and cold air condition during 3 months (March 2016 to May 2016). In this study, the concentration of respirable particles within the breathing zone of 70 workers who were working at different production worksites of a cement factory (Packing worksite, Cement mill, Grill and Greater cooler, kiln, blending, Raw material storage and Mine and crushing) was evaluated. The standard method of 0600 recommended by the National Institute of Occupational Safety and Health (NIOSH) was use to evaluate time weighted average (TWA) of workerschr('39') exposure to respirable cement particles. Workerchr('39')s exposure was measured using a personal sampling pump (SKC, model 224-44MTX, UK) with a 2.5 L.min-1 flow rate,   air was passing through an aluminum cyclone (SKC, UK) with a 37 mm 2 micrometer pore size poly vinyl chloride (PVC) filter (SKC, UK) bedding on a plastic cassette. The filters were placed in the desiccator for 24 hours before sampling time. To weigh the filters, a microbalance accurate to 6 decimal places (1 µg sensitivity   Sartorius, Model ME5, Germany) was used. Critical orifice was used to keep the flow constant during sampling period. Workers personal sampling carried out continuously during a complete shift time. A blank filter was used for each batch of samples to eliminate sampling errors. To evaluate workerschr('39') exposure to heavy metals including lead, chromium and cadmium within the cement respirable particles, the standard method of ID121 recommended by the Occupational Safety and Health Administration (OSHA) was applied. Each filter was dissolved separately at 100 ° C in concentrated nitric acid and perchloric acid until its metals were dissolved in the solution phase. Then, the solution obtained with deionized water was diluted to the lowest level of detection (LOD). The US-made FAAS Model VARIAN 240FS atomic absorption device was used for analysis. Firstly the standard curve was obtained using standard solutions with different concentrations of meals. Samples were then transferred to the atomic absorption apparatus to determine the concentration of the metals within solution. By measuring the sample absorption rate and comparing with the calibration curve and using Bier Lambertchr('39')s law, the amount of metal elements in the unknown sample was obtained. Semi quantitative risk assessment of heavy metals among exposed workers was carried out using a standard method provided by the Institute of the occupational health and Safety in Singapore. Finally, the risk level for each of the heavy metals (lead, chromium and cadmium) in the respirable cement particles was obtained. The degree of exposure (ER) for all parts of the plant was obtained. Since the mean concentrations of these metal in the air of all sections of the cement plant were below the exposure limit recommended by the Iranian Occupational Health Technical Committee (OEL) and the (TLV) recommended by the ACGIH, the E/OEL ratio was lower than one. The hazard rating (HR) of the chemicals was determined using a standard table. Then, the exposure rating (ER) was calculated and determined using air monitoring results using E that is the weekly exposure in milligram per cubic meter or parts per million, F is the number of exposures per week, D is the average time of each exposure in hours, M is the exposure rate in parts per million or milligram per cubic meter, W is the average working hours per week (40 h). Finally, the risk rate (RR) was calculated using the chemical hazard risk (HR) and exposure rate (ER) values.

This study showed that the mean concentrations of cadmium, lead and chromium elements were measured as 2.41, 10.39, and 1.36 microgram per cubic meter respectively. The highest average exposure to lead metal in the respirable cement particles was 15.09 ± 4.45 µg / m3 and the lowest mean was 8.48 ± 3.11 µg / m3. The highest mean chromium concentration in cement respirable particles was 2.27 ± 1.15 µg / m3 and the lowest mean was 1.11 ± 0.48 µg / m3. The highest mean concentration of cadmium in the cement respirable particles was 2.78 ± 0.62 µg / m3 and the lowest mean was 2.17±0.37 µg / m3.Most workers in the various cement worksites were exposed to heavy metals less than the OEL suggested by the Iranian Occupational Health Technical Committee and the TLV recommended by the ACGIH. Due to the toxicity of lead metal, the grade 3 risk was considered for this metal. According to the E / OEL ratio, the exposure rate (ER) for all parts of the plant was 1, and since the concentration of this metal in all parts of the cement plant was less than the OEL designed by the Iranian Occupational Health Technical Committee and the TLV recommended by the ACGIH. the risk score for all parts of the plant was 1.73, and finally the risk score for lead in all parts of the plant was low. Due to the toxicity level of chromium metal, the hazard rate (HR) for this metal was considered 5. According to the E / OEL ratio, the exposure rate (ER) for all parts of the plant was obtained 1and since the concentration of this metal in all parts of the cement plant is less than the OEL designed by the Iranian Occupational Health Technical Committee and the TLV recommended by the ACGIH, the risk score was 2.23 in all parts of the plant. And the risk rating for chromium metal was low in all parts of the plant. Due to the toxicity level of cadmium metal the (HR) was considered 4 for this metal. Risk score was obtained in all parts of factory number 2 and as a result the risk rating for cadmium metal in all parts of factory was low. Since all workers in a section are exposed to cement respirable particles and therefore exposed to lead, chromium and cadmium metal elements in these particles are different. The risk of exposure to workers exposed to the highest concentrations of the studied metals in the three sections of kiln, blending, and Cement mill was calculated separately. The results showed that workers exposed to cadmium and lead metals were in the medium risk exposure kiln and blending worksites, respectively and workers exposed to chrome metal working in the cement mill were also at low risk. 

According to the present study, concentrations of chromium, cadmium and lead in the respirable cement particles were lower than the exposure limit set by the Occupational Health Technical Committee of Iran (OEL) and (TLV) recommended by the ACGIH. Exposure to lead, chromium and cadmium elements in cement respirable particles were at a low risk rates for all worksites of the plant However, some workers in the kiln silo and milling materials that exposed to higher particle concentrations containing cadmium and lead had an average risk rate. Therefore, engineering and management control strategies for heavy metal exposure in those sectors are recommended to reduce the risk and prevent injury to these workers.

Formaldehyde (FA) is a colorless toxic gas used as a disinfectant and preservative and known as a carcinogen and strong irritant. Due to its germicidal, preservative and fixative properties, formaldehyde or other chemicals that potentially produce formaldehyde, are used in some cosmetics. OSHA has warned about hair dresser’s exposure to FA higher than threshold limit values. Because of the importance of this air pollutant and the lack of enough studies in Iran, the present study aimed at occupational monitoring of FA exposure in hair salons in Hamedan and Kermanshah cities.
Short term (n=20) and long term (n=45) air samples were collected on sorbent tubes in the breathing zone of selected hair dressers and then analyzed based on methods NIOSH 2016 and 2541, respectively.
The concentrations of FA in short-term and long-term samples were in ranges of 0-0.6935 and 0-0.6034 ppm, respectively. There were no statistically significant differences between mean concentrations of FA in long- term and short-term samples and also between studied work tasks (based on used cosmetics).
According to obtained results, the concentration of FA in some samples was higher than Iran’s OEL (0.3 ppm). Therefore, it is necessary to do more occupational exposure monitoring and apply control measures such as installing proper ventilation systems, correcting the existing systems, supervising the quality of cosmetics, and training programs for target group.

Occupational exposure to crystalline silica increases the risk of lung cancer and restrictive lung disease with extensive fibrosis. Silica dust is a major health hazard in foundry factories. The aim of this study was to determine core making workers’ exposure to respirable crystalline silica dust in a foundry factory.
Material and This cross-sectional study was conducted in core-making unit of a foundry factory in 2015. Occupational exposure of 55 workers to respirable crystalline silica aerosols was evaluated by using the improved NIOSH7602 method in core-making unit. Risk assessments for silicosis and excess lifetime risk of mortality from lung cancer were done according to Manettej and Rice models¡ respectively. Data was analyzed with Spss19 software.
The mean of respirable crystalline silica dust was 0.246 ± 0.351 (mg/m3). All workers’ exposure to respirable crystalline silica was higher than recommended occupational exposure limits. Silicosis mortality risk and excess lifetime risk of mortality from lung cancer were estimated in the range of 6-63 and 65 per thousand people¡ respectively.
The mean of workers’ exposure to respirable crystalline silica was higher than recommended occupational exposure standards in core making unit. The risk assessment of silicosis mortality and excess lifetime risk of mortality from lung cancer were higher than acceptable levels of risk.

Background and Personal exposure to volatile organic compounds can cause variety of adverse health effects, containing a large range from non-cancer effects up to cancer. The purpose of this study was quantitative risk assessment of occupational exposure to Volatile Organic Compounds in the oil-dependent chemical industry. In this cross sectional study NIOSH 1501& 2549 methods were applied for sampling and analyzing the amount of hydrocarbons in the oil-dependents of chemical and after detecting hydrocarbons, the quantitative risk assessment was calculated by United States Environmental Protection Agency method. Also the Hazard Quotient parameter for non-cancer VOCs and Life time Cancer Risk for cancer VOCs were calculated. The collected data were analyzed by SPSS16 software. The Life time Cancer Risk (LCR) of benzene for 13complexes were Definite and for 8 complexes, in all complexes that have been studied, the LCR of benzene were more than threshold limit recommended by WHO. The Lifetime Cancer risk of trichloroethylene in one complex and ethyl benzene in two complexes were Definite. The Hazard Quotient of xylene, chlorobenzene, methyl ethyl ketone and N-hexane in several complexes were more than values recommended by WHO. There are significant relationships between carcinogenic hydrocarbons risk and parameters like age and work history, with the correlation coefficient of 0.336 and 0.409 respectively (P< 0.001). This method ofrisk assessment is comprehensive and achieved results can be used for correcting and controlling prioritization of resources in case of reducing the level of risk.

Color vision is an important function of the visual system. Therefore، this study was aimed to evaluate the effect of chronic occupational exposure to detergents on color vision ability in different group. This descriptive study was conducted in a detergent producer factory on all (300) workers who were in detergents production hall. After considering exclusion criteria، 279 persons were qualified to participate in the study. General visual exam and color vision test was performed for participants. Their color vision was evaluated by Ishihara and Farnsworth D-15. 12. 9% of participants showed color vision disorder، the prevalence of which was mostly related to powder groups. Chronic occupational exposure to excess amount of detergents can cause acquired color vision disorder.

Today، Needle Stick Injuries (NSI) are very important occupational hazards experienced by healthcare workers lead to exposure to blood-borne viruses especially hepatitis B، hepatitis C and HIV. The aim of this study was to determine needle sticks injuries among heath care workers in emergency medical centers in Tehran University of Medical Sciences hospitals (2007-2010) In this descriptive study 991 heath care workers worked in emergency wards in Tehran University of Medical Sciences hospitals were followed for needle stick events from 2007 to 2010. Sampling method was census. Data were collected by a researcher-made questionnaire consisted of 32 questions included demographic variables and NSI included the event that leads to needle stick injuries. Content and face validity and also test-retest reliability (r = 0/71) were measured and data was analyzed by SPSS 16. The study population reported 167 needle stick injuries during the study period (167 heath care workers exposure group، 554 heath care workers not exposure group). Incidence rate of NSI was 16/85%. Majority of subjects in exposure group were female (50/89%)، married (52/69%) and nurse (53/2 %) and also the mean age was 35/3 6/4. In most cases، needles (55/08%) and vein catheter (22/75%) were responsible for injuries. IV access (24/7%) and recapping of needles (23/3%) were most common action resulted to exposure. There weren''t statistically significant different in demographic variables except working experience between exposure groups and not exposure group. According to the results of this study، incidence rate of NSI among HCWs worked in emergency wards in TUMS less than other studies in different countries. This might be an indication of inadequate reporting. It is suggested that، NSI in hospitals should be managed through obtaining an appropriate reporting system and organizing blood and body fluid exposure surveillance system.

Cement dust is one of the workplace harmful chemicals. There is a disagreement about respiratory effects of cement. The main purpose of this study was to investigate the respiratory effects of exposure to cement dust.

The subjects consisted of 148 male workers (94 workers with current exposure to cement dust and 54 healthy unexposed employees as a referent group). Respiratory symptom questionnaires, as suggested by the American Thoracic Society, were administered to them. Determination of exposure was carried out by personal dust monitoring. Furthermore, the subjects underwent lung function tests by a spirometer. The data were analyzed applying t test and chi-square test.

The mean values of respirable and dust concentrations were estimated to be 7.70± 1.2 and 67.4± 5.4 mg/m3. Significant decrements in the parameters of pulmonary function were noted (p<0.05).

The findings of this study indicate that a strong association exists between exposure to cement dust and the prevalence of respiratory symptoms and functional impairments of the lungs.