Journal of Health and Safety at Work

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Introduction: Exposure to crystalline silica dust can seriously threaten health of workers engaged in processes such as casting, stone crushing, grinding, construction activities, insulator manufacturing, and glassblowing and sandblasting. The aim of this study was to assess occupational exposure to crystalline silica and to determine the risk of mortality from silicosis and lung cancer in an insulator manufacturer.

Material and Method: Air personal sampling was performed using 10 mm nylon cyclone and mixed cellulose ester (MCE) membrane filters (5 mm diameter, 0.8 μm pore size) for 60 male workers. Samples were prepared and analyzed according to the National Institute for Occupational Safety and Health (NIOSH) 7601 standard method. The risk assessment of mortality due to silicosis resulting from crystalline silica exposure was done by using model of Mannetje et al. for the period of 10 years. The mortality rate of lung cancer was determined using a linear regression model derived from the study Rice et al.  

Result: The highest and lowest exposure levels to silica were belonged to the packing unit (0.54±0.28 mg/m3) and the furnace (0.02±0.01 mg/m3), respectively. Crystalline silica concentrations for all samples were higher than Threshold Limit Values (0.025 mg/m3) recommended by the American Conference of Governmental Industrial Hygienists (ACGIH). According to Mannetje et al. model, the cumulative exposure of 25% workers was in the range 0 to 0.99 that it represents 1 death per 1,000 people. The risk of mortality due to lung cancer was obtained in the range of 7-94 persons per 1000 workers exposed to silica.

Conclusion: In general, the geometric and arithmetic mean of crystalline silica exposure was higher than threshold limit value for most of the subjects. For all workers of the insulator manufacturer, the risk of silicosis related mortality was higher than 1/1,000 (unacceptable level of risk). Predicting the lung cancer mortality from silica exposure indicated a high level of mortality risk among understudied workers.

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Introduction: Adverse effects of volatile organic compounds (VOCs) including general and specific effects like carcinogenic of benzene are well known. The aim of this study was to evaluate occupational exposure to BTEX compounds in the painting unit of an automotive industry and subsequently health risk assessment of exposure to these compounds.

Material and Method: This cross-sectional study was conducted in the paint unit of an automotive industry including painting cabin, pre-painting salon and painting salon sections. After analyzing samples, gathered from different sections, by GC-MS, BTEX compound were identified as the main contaminants. In the next step, NIOSH1501 and EPA methods were used to measure and analysis of BTEX and risk assessment, respectively.

Result: Findings showed that benzene concentration in painting cabin was higher than occupational exposure limits provided by the Environmental and Occupational Health Center of Iran. Life time cancer risk for benzene per 1000 has been reported10, 3.63 and 1.27in the painting cabin, pre-painting and salon sections, respectively. It was also for ethyl benzene 2.5m 1.8 and 38.0 in the mentioned sections, respectively. The non-cancer risk for benzene and xylene in the painting cabin and pre-painting sections were higher than recommended allowable level.

Conclusion: Regarding the high level of cancer risk values obtained for benzene and ethylbenzene in the studied units and also high values of non-cancer risk for benzene and xylene, it is recommended to conduct biological exposure assessmnet of the workers and improve existence control systems using modern engineering control systems.

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Introduction: One of the harmful pollutants in the indoor environments is particulate matters. Particles smaller than 2.5 micrometer in diameter that are suspend in the industrial environments air are the most deleterious dusts which can cause lung disease and cancer. In present study PM2.5 concentration in the fast-food shops air and its cancer risk for shop workers were assessed.  
Material and Methods: In this descriptive-analytical study, all of Sari city 132 fast foods were included. Air sampling was conducted by calibrated real-time GRIMM-monitor device. Data were analyzed by using of SPSS16 and Prism6 software with T-test, Pearson correlation and descriptive statistics. Finally PM2.5 cancer risk in workers was calculated by EPA method equation.
Results: The PM2.5 concentration in shops indoor air (308.5µg/m3) significantly was higher than its concentration in outdoor air (121.98µg/m3) (p<0.05). Highest correlation was observed between indoor PM2.5 concentration with smoking (0.366) and local ventilation (-0.384) (p<0.01). The concentration PM2.5 in the indoor and the outdoor of shops was 273.55 and 86.98µg/m3 higher than acceptable level respectively. Cancer risk was 5.6 per 100 thousands and 1.97 per 10 thousands in the rest and cooking time respectively.
Conclusion: The most affective source in the elevation of PM2.5 level in shops indoor air is the cook-emitted particles. PM2.5 concentration in shops indoor and outdoor air was much higher than EPA admissible level and cancer risk for workers was unacceptable that it has required to basic solutions for air pollution control at source.

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Introduction: Lung cancer is the second most common cancer in the world. Smoking occupational and environmental exposures are the most important causes of lung cancer. Cadmium is known as a human carcinogen due to its ability to increase lung cancer risk. This study estimates the general results of all studies on the relationship between cadmium and lung cancer.
Material and Methods: In the present study, studies that evaluated the relationship between cadmium and lung cancer until May 2022 were searched and retrieved. From the funnel plot to determine the existence of diffusion skew, from the statistical tests Chi-squared test (x2) and I2 to determine heterogeneity, from the meta-regression method to identify the root of heterogeneity, and from the sensitivity analysis approach to identify the effect of each study on the result, it was generally used. This study performed all analyses with Stata statistical software version 15.
Results: In this study, it was observed that the chance of developing lung cancer compared to the base group, in the people exposed to a higher dose than the base level of cadmium is equal to 1.31 (95% CI: 1.06-1.62; p-value = 0.024), which is statistically significant. Based on Egger’s test (p-value = 0.178) and Begg’s (p-value = 0.276), no diffusion bias was observed in this study.
Conclusion: ccording to the final results of this review research, exposure to cadmium leads to a 31% increase in lung cancer risk, which is statistically significant. Therefore, cadmium is a risk factor for lung cancer.