Application of Multiple Occupational Health Risk Assessment Models for Crystalline Silica Dust among Stone Carvers.

OBJECTIVE: Silica is the most abundant substance on the Earth's crust and is a proven carcinogen. The aim of this study was to measure the occupational exposure of stone carvers to crystalline silica and to evaluate the health risks.  Methods: This descriptive and analytical cross-sectional study was performed on 79 stone carvers. Inhalation air sampling was performed by the NIOSH7500 method and the amount of silica was determined by X-ray diffraction (XRD). Semi-quantitative and quantitative risk assessments were performed using the methods of the Singapore Department and the US Environmental Protection Agency (EPA), respectively. Mortality due to silicosis and lung cancer were estimated using the Manettej and Rice models. Data were analyzed using SPSS23 software. RESULTS: The mean exposure to total inhalable dust and crystalline silica among the stone carvers was 1.44 and 0.5 mg/m3, respectively. Exposure to total dust and silica was significantly higher than the occupational standard (P <0.0001). Stone carvers' exposure to silica was at very high-risk level, and the carcinogenicity of silica considering two cancer slopes was 7.40 × 10-6 and 3.12 × 10-7 and the risk of non-carcinogenicity was unacceptable. CONCLUSION: The mortality rate due to silicosis was between 3 and 12 people per thousand, and due to lung cancer was 150.24 people per thousand. Based on the results of risk assessment, serious control measures should be implemented in order to reduce workers' exposure to silica.

Carcinogenic risk assessment and changes in Spirometric indices in casting and welding workers exposed to Metal fumes.

INTRODUCTION: The aim of this study was to investigate exposure to dust, and metal fumes, changes in pulmonary function indices among industrial workers to estimate the carcinogenic and non-carcinogenic risk of exposure to occupational metal fume.

Methods: This cross-sectional study was performed on 98 workers exposed to metal fumes. Air sampling was performed according to the NIOSH 0500 method and was analyzed by gravimetry and metal levels were analyzed by atomic absorption spectrometry. Spirometric results for 2010-2016 were collected. Carcinogenic and non-carcinogenic risk assessments were performed according to the US Environmental Protection Agency guidelines. Data were analyzed by SPSS 20 software. RESULTS: The mean occupational exposure of the subjects to workplace dust and iron fumes was 15.95 ± 6.65 mg/m3 and 13.18 ± 3.06 mg/m3 respectively. During these 6 years, the FVC (P=0.04), PEFR (P=0.04), and FEV1 (P=0.03) indices decreased significantly among welders, but there was no significant difference between FEV1/ FVC indexes. Also, the mean of FEV1 and PEFR decreased significantly amongst casting workers, but FVC and FEV1/ FVC had no significant difference. Multivariate regression showed that in both jobs, BMI and work history were related to pulmonary function indices. The mean total excess ifetime carcinogenic risk (ELCR) of hexavalent chromium in the study population was 0.708 per 1000 people and the mean non-carcinogenic risk of hexavalent chromium was HQ = 19.62. CONCLUSIONS: The results showed that exposure to metal fumes in casting and welding jobs reduces pulmonary function indices. Although the average occupational exposure to hexavalent chromium is lower than the recommended limit and the risk of carcinogenesis is within an acceptable range, the risk of non-carcinogenic effects among workers is significant Therefore, it is important to prevent this problem, by adequate ventilation and using respiratory masks.

Changes in Spirometry Indices and Lung Cancer Mortality Risk Estimation in Concrete Workers Exposed io Crystalline Silica.

The health of workers in the concrete and cement industries can be at risk due to occupational exposure to silica dust. The purpose of this study was to evaluate the changes of pulmonary parameters and risk of mortality from lung cancer in concrete workers exposed to crystalline silica. This cross-sectional study was performed on 72 male workers exposed to silica at a concrete manufacturing plant in Neyshabur, Iran. Respiratory zone air sampling was performed using the standard NIOSH7602 method using individual sampling pumps and membrane filters. Then, the amount of silica in the samples was determined using the Fourier Transform Infrared technique. The risk of death from lung cancer was determined using Rice et al.'s model. Respiratory indices were measured using a spirometer. Data were analyzed by the SPSS 20 software. Occupational exposure to silica was 0.025 mg/m3 and mortality was estimated to be 7-94 per thousand. All spirometry indices significantly decreased during these 4 years of exposure to silica dust. The respiratory pattern of 22% of the exposed workers was obstructive and this prevalence was significantly higher than the control group. The results showed that although the average occupational exposure to silica in these concrete workers was below the recommended threshold of national and international organizations, their risk of death was significantly higher; and workers' lung indices had significantly decreased over four years. Therefore, appropriate measures should be taken to reduce silica exposure among these workers.

Effect of occupational exposure to petrol and gasoline components on liver and renal biochemical parameters among gas station attendants, a review and meta-analysis.

OBJECTIVES: Kidney and liver are of the most affected organs during permanent exposure to petrol and gasoline components in gas stations. This study aims to investigate the renal and liver involvements in these workers using meta-analysis. METHODS: PubMed, Scopus, Science direct, ISI web of science, and Google scholar motor engine were searched using Mesh terms of the relevant keywords. Screening of titles, abstracts and full texts was continued until the eligible articles meeting the inclusion/exclusion criteria were selected. Quality assessment was conducted using NOS (Newcastle-Ottawa Quality score). The pooled standard mean difference of the renal and liver indices between exposed/unexposed groups was estimated using Stata ver. 11 software. RESULTS: In this systematic review, 22 papers were entered. The pooled standard mean difference (95% confidence interval) between exposed and unexposed groups was estimated as of 0.74 (0.28, 1.21) for alkaline phosphatase (ALP), 2.44 (1.80, 3.08) for aspartate transaminase (AST), 2.06 (1.42, 2.69) for alanine transaminase (ALT), 0.10 (-0.09, 0.29) for total Bilirubin (TB), 0.74 (-0.42, -1.90) for total protein (TP), -0.49 (-0.82, -0.15) for albumin, 0.88 (-0.10, 1.87) for uric acid, 1.02 (0.45, 1.59) for creatinine and 1.44 (0.75, 2.13) for blood urea nitrogen (BUN). CONCLUSION: Our meta-analysis showed that the serum AST, ALT, ALP, total protein, total bilirubin, BUN, uric acid and creatinine levels were higher among workers exposed to petrol and gasoline than control group, while albumin was lower in the serum of the exposed workers. Therefore, occupational exposure to gasoline stations can create adverse effects on kidney and liver function.

The effect of occupational exposure to petrol on pulmonary function parameters: a review and meta-analysis.

Introduction Exposure to petrol and gasoline can have harmful effects on the lungs. This review aimed to summarize the reported effects of this exposure on pulmonary function parameters. Methods Relevant studies were identified by a comprehensive search in PubMed, Scopus, Science Direct and Google Scholar databases. Irrelevant studies were excluded. Quality assessment was performed using the Newcastle-Ottawa score (NOS). The standard mean difference of pulmonary parameters between exposed and unexposed petrol station attendants was pooled using random effects. Meta-regression was used to investigate factors probably related to heterogeneity. Studies affecting the total estimates were assessed during sensitivity analysis. The Egger test was performed to investigate any evidence of publication bias. Results Eventually, 26 studies entered the meta-analysis, and the pooled standard difference [95% confidence interval (CI)] of forced vital capacity (FVC), forced expiratory volume in the first second (FEV1), FEV1/FVC, vital capacity (VC), peak expiratory flow (PEF), forced expiratory flow (FEF25-75) and maximum voluntary ventilation (MVV) in the exposed minus unexposed groups was -1.08 L (95% CI: -1.38, -0.78), -0.92 L (-1.15, -0.69), -0.65 (-1.01, -0.30), -0.51 L (-0.96, -0.06), -0.96 L/s (-1.21, -0.69), -0.78 L/s (1.14, -0.42) and -0.58 L/min (-0.90, -0.27), respectively, and showed a decrease in all pulmonary parameters in the exposed group. Conclusion Occupational exposure to petrol fumes is a risk factor for lung function and there is a reverse relation between lung function and the duration of exposure.

Investigation of thermal exposure in traditional neyshabur bakeries using heat strain and physiological indices.

Bakery is one of the occupations which are exposed to the high shear stress. The incidence of heat discomfort among traditional bakery workers is much more than machinery bakery. The aim of this study was to investigate the rate of heat strain index and temperature of drumhead under physical conditions in this group of workers. This cross-sectional study was conducted on 103 workers of the Bakeries in winter 2018. Heart rate and oral temperature were respectively measured using a heart rate meter and an oral thermometer. The Wet-bulb globe temperature (WBGT) index was recorded and the Heat Strain Score Index (HSSI) was completed simultaneously was used. Data obtained from this study were analyzed by comparing means, t test, and Person tests with the SPSS 20 software. The results of the assessment of WBGT, and HSSI showed that 28.69(1.41)and 15.02(2.6) percent of workers exposed to heat stress higher than permissible limits proposed by standard bodies. Also, the present study proved that the mean rate of Heat Strain indicating the presence of strain level 2. According to the results from this study, the oral temperature and drumhead were higher in workers who performed baking activity than other two groups. It is concluded that there is a significant relationship between Heat strain index and Distance of bakery floor ratio to stre.

Comparison of Four Search Engines and their efficacy With Emphasis on Literature Research in Addiction (Prevention and Treatment).

BACKGROUND: Surveying valuable and most recent information from internet, has become vital for researchers and scholars, because every day, thousands and perhaps millions of scientific works are brought out as digital resources which represented by internet and researchers can't ignore this great resource to find related documents for their literature search, which may not be found in any library. With regard to variety of documents presented on the internet, search engines are one of the most effective search tools for finding information. OBJECTIVES: The aim of this study is to evaluate the three criteria, recall, preciseness and importance of the four search engines which are PubMed, Science Direct, Google Scholar and federated search of Iranian National Medical Digital Library in addiction (prevention and treatment) to select the most effective search engine for offering the best literature research. MATERIALS AND METHODS: This research was a cross-sectional study by which four popular search engines in medical sciences were evaluated. To select keywords, medical subject heading (Mesh) was used. We entered given keywords in the search engines and after searching, 10 first entries were evaluated. Direct observation was used as a mean for data collection and they were analyzed by descriptive statistics (number, percent number and mean) and inferential statistics, One way analysis of variance (ANOVA) and post hoc Tukey in Spss. 15 statistical software. P Value < 0.05 was considered statistically significant. RESULTS: Results have shown that the search engines had different operations with regard to the evaluated criteria. Since P Value was 0.004 < 0.05 for preciseness and was 0.002 < 0.05 for importance, it shows significant difference among search engines. PubMed, Science Direct and Google Scholar were the best in recall, preciseness and importance respectively. CONCLUSIONS: As literature research is one of the most important stages of research, it's better for researchers, especially Substance-Related Disorders scholars to use different search engines with the best recall, preciseness and importance in that subject field to reach desirable results while searching and they don't depend on just one search engine.

Role of father-child relational quality in early maladaptive schemas.

BACKGROUND: Primary maladaptive schemas, which are the basis of high-risk behavior and psychological disorders, result from childhood experiences with significant objects, such as fathers, in different developmental phases. OBJECTIVES: This endeavor examined the role of the father in predicting these schemas. PATIENTS AND METHODS: A total of 345 Islamic Azad University students (Qom Branch) who were chosen through convenience sampling completed the Young Schema Questionnaire, the Parental Bonding Instrument, and the Parent-Child Relationship Survey. RESULTS: A multivariate regression analysis indicated that anumber of aspects of the father-child relationship, including care, emotional interaction, positive affection, the effective relationship, and excessive support, predict particular schemas. CONCLUSIONS: Therefore, these findings suggested that psychotherapists examine the different aspects of the father-child relationship when restructuring schemas.