Granite Workers Research Articles

Low-Level Respirable Crystalline Silica and Silicosis: Long-Term Follow-Up of Vermont Granite Workers.

The lifetime risk of silicosis associated with low-level occupational exposure to respirable crystalline silica remains unclear because most previous radiographic studies included workers with varying exposure concentrations and durations. This study assessed the prevalence of silicosis after lengthy exposure to respirable crystalline silica at levels ≤ 0.10 mg/m3. Vermont granite workers employed any time during 1979-1987 were traced and chest radiographs were obtained for 356 who were alive in 2017 and residing in Vermont. Work history, smoking habits and respiratory symptoms were obtained by interview, and exposure was estimated using a previously developed job-exposure matrix. Associations between radiographic findings, exposure, and respiratory symptoms were assessed by ANOVA, chi-square tests and binary regression. Fourteen workers (3.9%) had radiographic evidence of silicosis, and all had been employed ≥30 years. They were more likely to have been stone cutters or carvers and their average exposure concentrations and cumulative exposures to respirable crystalline silica were significantly higher than workers with similar durations of employment and no classifiable parenchymal abnormalities. This provides direct evidence that workers with long-term exposure to low-level respirable crystalline silica (≤0.10 mg/m3) are at risk of developing silicosis.

Occupational Injuries among Marble and Granite Processing Workers: A Comparative Study

Introduction: Marble and Granite are natural stones that can be shaped into blocks,slabs or tiles. Their production passes through several stages. The production processcould result in many injuries. Aim of Work: to detect the prevalence of workplaceinjuries, their predictors and causes among marble and granite workers. Materialsand Methods: A descriptive comparative cross-sectional study was conducted infour workshops at Damietta Governorate from June 1, 2016 to May 30, 2017. Thestudied groups were composed of an exposed group engaged in the marble andgranite processing and a comparison one who were not engaged in this industry (eachgroup comprises of 90 workers). They were subjected to an interview questionnaireasking about sociodemographic characteristics, occupational profile, injury profileand their anthropometric measurements were taken. Results: All marble and graniteworkers experienced one or more injuries in the past year compared to (13.3%) ofthe comparison group with highly statistically significant difference (p≤0.001).They showed high prevalence of superficial wounds, contusion/bruises, tear andlaceration compared to the control group. Unsafe working environment, usinginappropriate instruments, lack of protective equipment and nonadherence to donning them were the main causes of workplace injuries. Regarding predictorsfor injuries, workers with low income (being in debt) are 18 times prone to injuresthan those who can save money. Current smokers are 7.6 times than nonsmokers,unmarried workers are 6.61 times than married and who live in rural areas are 4.43times than others who live in urban areas. Conclusion: Providing safe workingenvironment, donning suitable protective equipment, implementing effective trainingprograms for all workers especially high-risk ones are crucial preventive measures.

A Study on Socio–Demographical Factors among Granite Industrial Workers of a District in India

A Study on Socio–Demographical Factors among Granite Industrial Workers of a District in India

Study of lung function in granite workers based on duration of exposure

Background: Stone quarry workers form a unorganized sector of industry scattered all over India. Due to these workers employed at the granite factory are exposed to different components of dust in which silica is the major one. Longer the duration of exposure to silica dust the respiratory impairment increases. High degree of respiratory morbidity is associated with this industry as people lack the knowledge about the harmful effects of the dust on their health and also negligence from the management side who fail to do periodic health checkup of the employees. Aims and Objectives: The present study was designed to evaluate the pulmonary function tests in the granite factory workers based on the duration of exposure. Materials and Methods: The study population consists of 100 asymptomatic granite workers aged between 18 and 40 years working in granite rock factory for more than 5 years’ duration. Workers were divided into two groups based on the duration of exposure. Workers who were exposed for >5 years but

Doses from radon-222 irradiation for workers of the granite mining industry

determining the integral value of annual effective dose from 222Rn for workers of the granite mining industry and assessment for the expected life effective dose from 222Rn. Materials were the results of measurements of external exposure dose of radiation measurements equiv alent equilibrium volume activity of 222Rn in workrooms and workplaces of major groups of granite quarry workers Mykolaiv region, studies EROA 222Rn air premises of these workers, research content 222Rn in drinking water. Granite quarry workers receive double radiation exposure of 222Rn due to exposure in the workplace and at home. The load in the workplace due to inhalation of 222Rn the air was (2.1 ± 0.2) mSv / year (vari ation 0.9-5.9) in a residential area - (4,1 ± 0,2) mSv/year (variation 1.8-5.9). The total annual effective dose from internal exposure from air flow and working premises and drinking water was on average (6,5 ± 0,2) mSv/year, equal to a maximum value of 20 mSv/year. The expected life for the chronic exposure dose of technological naturally occurring radioactive sources for people who work in the granite quarries and, while living in high risk from radon is in the range of 0.16-1.12 Sv. The research results indicate that in assessing the effects associated with exposure due to radon 222 contingents persons such surveys must take into account all sources of this radionuclide dose.

Lung-cancer mortality among Vermont granite workers: factors influencing exposure–response evaluation

ObjectiveTo understand why 2 studies relating crystalline silica exposure to lung-cancer mortality in Vermont granite workers yielded conflicting results.MethodsData used in the 2 studies were linked to identify discrepancies. Mortality...

Radiation dose to workers due to the inhalation of dust during granite fabrication

There has been very little research conducted to determine internal radiation doses resulting from worker exposure to ionising radiation in granite fabrication shops. To address this issue, we estimated the effective radiation dose of granite workers in US fabrication shops who were exposed to the maximum respirable dust and silica concentrations allowed under current US regulations, and also to concentrations reported in the literature. Radiation doses were calculated using standard methods developed by the International Commission on Radiological Protection. The calculated internal doses were very low, and below both US occupational standards (50 mSv yr−1) and limits applicable to the general public (1 mSv yr−1). Workers exposed to respirable granite dust concentrations at the US Occupational Safety and Health Administration (OSHA) respirable dust permissible exposure limit (PEL) of 5 mg m−3 over a full year had an estimated radiation dose of 0.062 mSv yr−1. Workers exposed to respirable granite dust concentrations at the OSHA silica PEL and at the American Conference of Governmental Industrial Hygienists Threshold Limit Value for a full year had expected radiation doses of 0.007 mSv yr−1 and 0.002 mSv yr−1, respectively. Using data from studies of respirable granite dust and silica concentrations measured in granite fabrication shops, we calculated median expected radiation doses that ranged from <0.001 to 0.101 mSv yr−1.

Evaluation of cytotoxic, genotoxic and inflammatory responses of micro- and nano-particles of granite on human lung fibroblast cell IMR-90

Occupational exposure of granite workers is well known to cause lung impairment and silicosis. Toxicological profiles of different size particles of granite dust, however, are not yet understood. Present evaluation of micro- and nano-particles of granite dust as on human lung fibroblast cells IMR-90, revealed that their toxic effects were dose-dependent, and nanoparticles in general were more toxic. In this study we first demonstrated that nanoparticles caused oxidative stress, inflammatory response and genotoxicity, as seen by nearly 2 fold induction of ROS and LPO, mRNA levels of TNF-α and IL-1β, and induction in micronuclei formation. All these were significantly higher when compared with the effect of micro particles. Thus, the study suggests that separate health safety standards would be required for granite particles of different sizes.

Respiratory symptoms and ventilatory function among granite workers working in quarries installed with mechanical crushers in and around Kandy Municipality limits

Objectives: To compare the presence of selected respiratory symptoms among granite workers with a control group and to assess ventilatory function (VF) and radiological changes in the lungs of granite workers. Methods: A cross-sectional analytical study was conducted on workers employed in the granite quarries in-stalled with mechanical crushers in and around the Kandy Municipality limits. The control group comprised persons accompanying patients to the outpatient department of a tertiary care hospital. The respiratory symptoms were compared using an interviewer administered questionnaire. Only granite workers were subjected to spirometry and chest radiography. Forced vital capacity (FVC), forced expiratory volume in the first second of FVC and peak expiratory flow rate were assessed. The observed values of above were compared with predicted normal values. Chest radiographs were read by two radiologists conforming to ILO classification of radiographic appearances. Results: There were 51 granite workers and 51 controls. A higher proportion of granite workers had chronic cough (8%; n=4), and phlegm (16%; n=8) of ≥3 months duration and chronic bronchitis (16%; n=8) in comparison to the control group (2% [n=1], 6% [n=3] and 8% [n=4] respectively) but the differences were statistically not significant. A significantly higher proportion in the control group had dyspnoea (45%; n=23) and at least a single respiratory symptom (55%, n=28) in comparison to the granite workers (10% [n=5] and.31% [n=16] respectively). The observed values of the three respiratory indices were significantly lower than the predicted norms. Twenty four (47%) had a restrictive type and one (2%) an obstructive type of ventilatory impairment. None had radiological evidence of silicosis or tuberculosis. Conclusions: Ventilatory function of granite workers were affected significantly. Proportions with cough and phlegm of equal or more than three months duration and chronic bronchitis were higher among granite workers even though statistical significance was not reached. Proportions with dyspnoea and at least one respiratory symptom was significantly less among granite workers. There was no radiological evidence of silicosis or tuberculosis. Installation of exhaust ventilation, use of industrial masks and limitation of exposure time is recommended. Key Words: Granite workers; Ventilatory impairment; Respiratory symptoms DOI: 10.4038/jccpsl.v13i2.2963 Journal of the College of Community Physicians of Sri Lanka Vol.13(2) 2008 9-16

Silica Exposure Assessment in a Mortality Study of Vermont Granite Workers

A study of past silica and respirable dust exposures in the Vermont granite industry was conducted to develop a job exposure matrix (JEM) that used 5204 industrial hygiene measurements made from 1924–2004. The construction of the JEM involved data entry from several original sources into an Excel database that was reviewed later to ensure accuracy. Exposure measurements by job or location were grouped in two broad categories of quarry or shed and then into 22 job classes. Missing exposure data by time period were computed, taking into account improvements in dust control and periods of significant reduction in dustiness. Percent free silica (α-quartz) in respirable dust was estimated to be 11.0% based on previous published studies in Vermont and on data in the current database. About 60% of all measurement data (primarily from years prior to 1972) were obtained using the impinger and expressed in millions of particles per cubic foot (mppcf), which were converted to equivalent respirable free silica concentrations using the conversion of 10 mppcf = 0.1 mg/m3 of respirable silica. For impinger data, respirable dust was calculated by multiplying respirable silica by a factor of 9.091 to reflect that the respirable silica was 11.0% respirable dust. This JEM has been used in a recent epidemiologic study to assess mortality in Vermont granite workers and to examine the relationships among mortality from silicosis, lung cancer, and other nonmalignant respiratory diseases.

Mortality in Vermont granite workers and its association with silica exposure

ObjectivesTo assess mortality in Vermont granite workers and examine relationships between silica exposure and mortality from lung cancer, kidney cancer, non-malignant kidney disease, silicosis and other non-malignant respiratory disease.MethodsWorkers employed...

High Prevalence and Advanced Silicosis in Active Granite Workers: A Dose-Response Analysis Including FEV1

To evaluate silica exposure and respiratory disease in granite workers. A cross-sectional study of 440 active granite workers. Seventy-seven (17.5%) have silicosis, complicated in 15 of them; 18 have an obstructive ventilatory defect and 73 had exceeded 3.5 mg/m-year of cumulative silica exposure. Percent predicted FEV1 have a significant negative relation with mg/m(3)-year (P < 0.001) with a trend toward dose-response excluding silicotics and controlling for tobacco. The odds ratio (95% confidence interval) of having a percent predicted FEV1 below 50th percentile is 1.18 (0.66 to 2.11) for nonexposed smokers, 1.47 (0.76 to 2.84) for exposed nonsmokers, and 2.07 (1.12 to 3.85) for exposed smokers, in comparison with the control group. This study suggests that silica induces functional alteration regardless of silicosis and, in all likelihood, synergistically with tobacco. Exposure levels must be controlled better in these workers and those with silicosis must be relocated to risk-free jobs or retired.

Reducing healthy worker survivor bias by restricting date of hire in a cohort study of Vermont granite workers

Objective:To explore the healthy worker survivor effect (HWSE) in a study of Vermont granite workers by distinguishing “prevalent” from “incident” hires based on date of hire before or after the...

Respiratory disease and cardiovascular morbidity

Background: Work related dust exposure is a risk factor for acute and chronic respiratory irritation and inflammation. Exposure to dust and cigarette smoke predisposes to exogenous viral and bacterial infections...

Symptoms And Lung Function Values In Nigerian Men And Women Exposed To Dust Generated From Crushing Of Granite Rocks In Calabar, Nigeria

This study was carried out to determine lung function and respiratory and non-respiratory symptoms among men and women exposed to dust emitted from crushing of granite rocks and to compare them with control men and women not exposed to any known air pollutant. The sites were the granite rock crushing industries in old Netim, Akamkpa Local Government Area of Cross River State, Nigeria. Respirable dust level was higher in the dust-emitting sites (1.087±0.243mg/m 3 ) than in the control areas (0.099± 0.007 mg/m 3 ; p 1 % were significantly lower in the dust-exposed group than their control group. (p 1 , FVC and PEFR) thus, suggesting restrictive lung defect among the exposed workers. Lung function indices correlated negatively with duration of service of the granite industry workers. The incidence of the major respiratory symptoms viz: unproductive cough, chest pain, catarrh and dyspnoea among the test group were higher (p Key words: Lung function, Granite, Dust, Symptoms Nigerian Journal of Physiological Sciences Vol.19(1&2) 2004: 41-47

336-S: The Healthy Worker Survivor Effect in the Vermont Granite Workers Study

336-S: The Healthy Worker Survivor Effect in the Vermont Granite Workers Study

RE: Attfield MD, Costello J. 2004. Quantitative exposure‐response for silica dust and lung cancer in Vermont granite workers. Am J Ind Med 45:129–138

RE: Attfield MD, Costello J. 2004. Quantitative exposure‐response for silica dust and lung cancer in Vermont granite workers. Am J Ind Med 45:129–138

Quantitative exposure-response for silica dust and lung cancer in Vermont granite workers.

Excess lung cancer mortality among the exposed Vermont granite workers has been reported. These studies were based on job and tenure surrogates, with the potential for misclassification and inability to evaluate quantitative exposure-response. Industrial hygiene data collected from 1924 to 1977 was analyzed in conjunction with mortality data to examine quantitative exposure-response for silica, lung cancer, and other lung diseases. A person-years analysis was undertaken by cumulative exposure group, including lagged and unlagged tabulations. Poisson models were fitted to untransformed and log transformed exposure. The results indicated a clear relationship of lung cancer, tuberculosis, pneumoconiosis, non-malignant lung disease, and kidney cancer with cumulative exposure. An exposure to 0.05 mg/m(3) from age 20 to 64 was associated with a lifetime excess risk of lung cancer for white males of 27/1,000. The results of this study of workers exposed almost exclusively to silica and no other major occupational confounding exposures indicate a clear exposure-response for lung cancer.

An evaluation of compliance with occupational exposure limits for crystalline silica (quartz) in ten Georgia granite sheds.

Since the 1920s, industrial hygiene studies have documented granite shed workers' exposures to crystalline silica, and the data from these studies have contributed to a better understanding of the relationship between silica exposures and adverse health effects, such as silicosis. The majority of these studies were conducted in the Barre, Vermont, granite sheds. However, a second major granite processing region is located in Elberton, Georgia, where approximately 1800 workers are employed in 150 granite sheds and 45 quarries. The current study reports the exposures of 40 workers in 10 granite sheds in Elberton, Georgia. The arithmetic mean exposure to silica for all monitored employees was 0.052 mg/m3. Employees were classified into one of seven job task groups. The job task group with the greatest exposure was the top polish group, which had a mean exposure of 0.085 mg/m3. Among the top polish workers, the greatest percentage of exposures above the Occupational Safety and Health Administration's permissible exposure limit (OSHA PEL) occurred among the workers who used dry grinders. Wet methods were effective in reducing these exposures to below the OSHA PEL. The mean exposure of Elberton granite shed workers was less than the OSHA PEL, but was not below the threshold limit value of the American Conference of Industrial Hygienists (ACGIH TLV), which was lowered in the year 2000 to 0.05 mg/m3. The Elberton granite shed workers provide a valuable cohort for research on the effects of exposure to crystalline silica at levels between the ACGIH TLV and the OSHA PEL. They are a relatively permanent worker population, are concentrated geographically, and have a quantitatively documented exposure to crystalline silica over the past twenty years.

Radiographic Abnormalities in Long-Tenure Vermont Granite Workers and the Permissible Exposure Limit for Crystalline Silica

This study was undertaken to assess the prevalence of radiographic abnormalities consistent with silicosis in a group of 600 retired granite workers who were receiving pensions. Files of regional clinics and hospitals were searched for chest radiographs taken on these men, and 470 x-ray films suitable for interpretation were located. After exclusions (women, and men who had worked in the granite industry elsewhere), 408 x-ray films were independently read by three experienced readers using the 1980 International Labour Office scheme. Dust exposures were estimated for workers hired after 1940, when the dust-control standard of 10 million particles per cubic foot (mppcf) (equivalent to 0.1 mg/m3) was put in place and monitored by the Vermont Division of Industrial Hygiene. Dust levels were initially high but were gradually reduced from 1940 to 1954, after which average quartz exposures stabilized to a mean of approximately 0.05 to 0.06 mg/m3; however, about 10% to 15% of samples after 1954 exceeded 0.1 mg/m3. Of the 408 x-ray films, 58 were taken on workers hired before dust controls were instituted in 1940, and 25.9% showed abnormalities (a profusion score of 1/0 or greater). A total of 350 x-ray films were taken on workers hired in 1940 or after, and the prevalence in this group was 5.7%. The radiographic changes in workers hired after 1940 are likely due to excessive exposures during the first 15 years of dust control. We conclude that if the exposure standard of 0.1 mg/m3 is rigorously observed in the workplace, radiographic abnormalities caused by quartz dust in long-term workers will be rare.