Effect of Exposure to Cement Dust among the Workers: An Evaluation of Health Related Complications

Carbon capture potential and environmental impact of concrete weathering in soil

The enhanced weathering of concrete in soil has potential to capture atmospheric CO2. The objective of this research was to conduct a laboratory experiment and evaluate the environmental impacts and carbon capture potential of concrete as an enhanced weathering material in soil. A column study was conducted with four treatments comprised of: 1) 100 % soil (S treatment), 2) 90 % soil and 10 % concrete by weight of 0.25-0.71 mm diameter fragments (S + Cfine treatment), 3) 90 % soil and 10 % concrete by weight of 8-25 mm diameter fragments (S + Ccoarse treatment), and 4) 100 % concrete composed of 8-25 mm diameter fragments (C treatment). Deionized water was added to the columns for 16 weeks. The S + Cfine treatment experienced a significant increase in soil pH (8.0 ± 0.07) compared to the S (6.9 ± 0.22) and S + Ccoarse (7.1 ± 0.08) treatments. The C treatment experienced a significant increase in leachate pH. Leachate NO3- concentrations in the S + Cfine (33 ± 18 mg L-1) samples were significantly greater than those in other treatments. Soil microbial community concentrations were significantly less in the S + Cfine treatment. The S + Cfine treatment had a calculated average HCO3- concentration of 350 ± 120 mg L-1 which was significantly greater than the S (230 ± 100 mg L-1), C (270 ± 170 mg L-1), and S + Ccoarse (260 ± 50 mg L-1) treatments. Increased concentrations of Ca2+, SO42-, H4SiO4, and HCO3- in the mixed concrete and soil samples are evidence that chemical reactions occurred due to the soil-concrete interaction and are likely capturing atmospheric CO2.

Impact of Occupational Cement Dust Exposure on Hematological Health Parameters: A Cross-Sectional Study

Introduction Contact with the dust of cement consisting of toxic components brings about inflammatory damage (often irreversible) to the body of a human being. The circulatory system exhibits sensitivity to inflammatory changes in the body, and one of the earliest changes may be observed in the blood parameters like mean corpuscular hemoglobin (MCH) and mean corpuscular hemoglobin concentration (MCHC). MCHC and MCH are possibly easily accessible and affordable parameters that can detect harmful changes in the body before any irreversible damage occurs. Objectives This research aimed to seek the changes in MCHC and MCH upon occupational contact with the toxic dust of cement. Methods The execution of this research was done in the Department of Physiology, Dhaka Medical College, Bangladesh, and a cement plant in Munshiganj, Bangladesh. This research was carried out between September 2017 and August 2018. Individuals (20 to 50 years old, 92 male adults) participated and were grouped into the group with occupational cement dust impact (46 subjects) and the group without occupational dust of cement impact (46 subjects). Data was collected in a pre-designed questionnaire. An independent sample t-test was conducted to analyze statistical and demographic data like body mass index and blood pressure. A multivariate regression model was applied to note the impact of cement dust on the group working in this dusty environment. Again, a multivariate regression model was employed to observe whether the duration of exposure to this dust affected MCHC and MCH. The significance level was demarcated at p < 0.05 Stata-15 (StataCorp LLC, College Station, TX, US) for statistical analysis, and GraphPad Prism v8.3.2 (Insight Venture Management, LLC, New York, NY, US) was employed to present the data graphically when required. Results There was a reduction in MCHC by 0.58 g/dL and MCH levels by 0.68 pg in the cement dust-exposed subjects when compared to controls, but not significant (95% CI: -0.93, 2.10; p  = 0.448 and 95% CI: -0.37, 1.73; p = 0.203, respectively). However, MCHC was reduced significantly by 0.51 g/dL (p = 0.011) with the duration of exposure to the dust. Conclusion The study showed that MCHC was significantly reduced with the duration of exposure to cement dust in cement plant workers. Such alterations may hamper heme synthesis, hemolysis, and inflammatory changes in the body.

The effective treatment of dye-containing simulated wastewater by using the cement kiln dust as an industrial waste adsorbent

This study compares the adsorption behavior of both Methylene Blue (MB) and Congo Red (CR) dyes on the surfaces of cement kiln dust (CKD) powder from the experimentally simulated wastewater solution. The cement kiln dust powder was characterized using X-ray Fluorescence (XRF), X-ray diffraction (XRD), N2 adsorption-desorption Brunauer-Emmett-Teller (BET), Fourier Transform Infrared Spectroscopy (FTIR), and Scanning Electron Microscopy (SEM) tests. The adsorption for such dyes was studied under varying mixing contact times, temperatures, and pH as well as various initial concentrations of both dyes and adsorbent using the batch mode experiments. Pseudo-first-order, pseudo-second-order, and intraparticle diffusion models were applied, and the results revealed that the pseudo-second-order fitted well to the kinetic data. Thermodynamic parameters stated that the adsorption process was endothermic. Studying Linear and nonlinear forms of Langmuir and Freundlich's adsorption isotherms revealed that the adsorption process was followed by both homogeneous mono-layer and heterogeneous multilayer coverage on the active sites of cement kiln dust particles. The data showed that the adsorption capacities of the methylene blue and Congo red dyes were 58.43 and 123.42 mg/g, respectively and cement kiln dust is an adsorbent with little cost for the treatment of wastewater.

Red Cell Distribution Width and Mean Corpuscular Volume Alterations: Detecting Inflammation Early in Occupational Cement Dust Exposure

Introduction Cement dust emitted during cement manufacture consists of toxic components. Occupational cement dust exposure may cause inflammation in the human body, which may be detected early by observing changes in blood parameters such as red blood cell distribution width (RDW) and mean corpuscular volume (MCV). Objectives The study aims to observe the effect of occupational cement dust exposure on RDW and MCV. Methods This study was performed in the Department of Physiology of Dhaka Medical College, Dhaka, Bangladesh, and a factory in Munshiganj, Bangladesh, from September 2017 to August 2018. Ninety-two participants between 20 and 50 years were included (46 subjects were occupationally exposed to cement dust, and 46 were not exposed to cement dust). A pre-designed questionnaire was used for data collection. An independent sample t-test was used to analyze basic information, such as blood pressure and BMI. The multivariate regression model was used to analyze the effect of cement dust exposure on the study group. The impact of cement dust exposure duration was analyzed using the multivariate regression model. The level of significance was p < 0.05. The statistical analysis was performed using STATA-15 (StataCorp, College Station, TX), and the graphical presentation used GraphPad Prism v8.3.2. Results The cement dust-exposed participants had a significantly higher value of MCV by 1.19 fi (95% CI = 0.02, 4.84; p = 0.049) and a 5.92% increase in RDW (95% CI = 5.29, 6.55; p < 0.001) than that of the control group. Conclusion The study reveals that exposure to cement dust causes significant changes in RDW and MCV. These changes may indicate hemolysis due to inflammation.

Prevalence of chronic respiratory symptoms among cement factory workers in Gauteng Province, South Africa

Cement workers are exposed to various kinds of occupational hazards, dust being the most hazardous. Despite certain exposure limits on the emission of air pollutants in place, several people die each year due to complications from respiratory disease. This study aimed to assess the prevalence of chronic respiratory symptoms among workers exposed to cement dust. A quantitative, descriptive cross-sectional design was employed among 81 workers from two cement production companies in Gauteng, South Africa in 2018. A self-administered questionnaire, anthropometric measurements, and a spirometry test were used as data collection tools. Data were analyzed using Wilcoxon rank sum, binary logistic regression, Pearson's chi-squared, and Fischer's exact tests. Respiratory symptoms such as wheezing, recurring blocked nose, sneezing/stuffy nose, fatigue/tiredness, rapid breathing, soreness/watery eyes, and breathlessness were significantly prevalent among participants from both facilities. Engineering and housekeeping control measures such as the use of High-Efficiency Particulate Air (HEPA) vacuums to clean up dust and proper use of Personal Protective Equipment (PPE) where workers are exposed to dust particles should be implemented.

Physicochemical characterization of particulate matter in a cement production plant

Employees working in cement production plants are exposed to airborne particulate matter (PM) which may lead to lung function impairments and airway symptoms. The PM consists of raw materials, clinker and additives which vary depending on cement blend. The aim of this work was to characterize the thoracic fraction of PM with regard to size, phase composition and mixing state. Both stationary and personal impactors were used to collect size-fractionated samples in a cement production plant in Norway. Stationary samples were measured with aerosol particle counters and collected with a 13-stage cascade impactor, which were stationed at three locations of the cement production plant: at the raw meal mill, clinker conveyor belt and cement mill. Sioutas cascade impactors, and thoracic and respirable dust samplers were used in parallel for personal sampling. Additionally, particles for electron microscopy were collected with the stationary cascade impactor for size-fractionated single particle characterization. Gravimetric measurements and element compositions of the samples from the stationary impactors show that the PM mass is dominated by calcium-rich particles of size >1 μm. The size distribution results of stationary and personal impactors were similar. Characterization of single particles reveals that limestone is the dominating material in the raw meal mill, whereas clinker and limestone dominate at the clinker conveyor belt and at the cement mill. The element composition of clinker PM did not change with particle size. The PM collected on impactor stages with aerodynamic diameter cut-offs below 0.56 μm was dominated by soot and volatile secondary particles at the three locations. The number of ultrafine particles of the cement related compounds was low. Air concentrations of PM in personal respirable and thoracic samples ranged from 0.14-10 mg m^-3 to 0.37-9.5 mg m^-3, respectively. Considerable local variations exist, both in composition and air concentration of the PM.

Quantitative computed tomography imaging-based classification of cement dust-exposed subjects with an artificial neural network technique

BACKGROUND AND OBJECTIVE

Cement dust exposure is likely to affect the structural and functional alterations in segmental airways and parenchymal lungs. This study develops an artificial neural network (ANN) model for identifying cement dust-exposed (CDE) subjects using quantitative computed tomography-based airway structural and functional features.

METHODS

We obtained the airway features in five central and five sub-grouped segmental regions and the lung features in five lobar regions and one total lung region from 311 CDE and 298 non-CDE (NCDE) subjects. The five-fold cross-validation method was adopted to train the following classification models:ANN, support vector machine (SVM), logistic regression (LR), and decision tree (DT). For all the classification models, linear discriminant analysis (LDA) and genetic algorithm (GA) were applied for dimensional reduction and hyperparameterization, respectively. The ANN model without LDA was also optimized by the GA method to observe the effect of the dimensional reduction.

RESULTS

The genetically optimized ANN model without the LDA method was the best in terms of the classification accuracy. The accuracy, sensitivity, and specificity of the GA-ANN model with four layers were greater than those of the other classification models (i.e., ANN, SVM, LR, and DT using LDA and GA methods) in the five-fold cross-validation. The average values of accuracy, sensitivity, and specificity for the five-fold cross-validation were 97.0%, 98.7%, and 98.6%, respectively.

CONCLUSIONS

We demonstrated herein that a quantitative computed tomography-based ANN model could more effectively detect CDE subjects when compared to their counterpart models. By employing the model, the CDE subjects may be identified early for therapeutic intervention.

Respiratory health evaluation of construction workers using questionnaire

Relevance . With growing economy and flourishing construction industries the comorbidities among construction workers are also raised. They are exposed to various dust, fumes, noxious gases and vapours making them susceptible to chronic airway diseases like Chronic Obstructive Lung Disease. The aim of the study was to evaluate the respiratory health status of construction workers in an unorganised sector. Materials and Methods . The data collected from National Capital of Delhi region in an unorganised sector of construction workers by using a Saint George Respiratory Questionnaire by the Institute of Occupational Health and Environmental research, Basaidarapur, Delhi, India. All the participant response was noted and the answers were evaluated to see respiratory health status of workers. Total 200 workers were evaluated. Total 182 males and 18 female participated in the study. Results and Discussion . 25% of workers reported poor health at the time of the survey, while only 4% of workers considered their health to be very good. Among the main complaints were indicated: cough, sputum production, shortness of breath, chest infections, attacks of wheezing. The overall mean of Saint George Respiratory Questionnaire core was 33.55. It increases with the working period in the construction field with 21.6% for 10years and 49.1 for 30years experienced workers, while workers with 11 to 20 years of experience, the score was 28.4. The Saint George Respiratory Questionnaire score was 35.1 in 21-30 years of experienced construction workers. Conclusion . As a result of the study, construction workers are found to be at high risk of various respiratory diseases and related disabilities. Participants in this study did not receive any treatment for respiratory problems at any clinic. This means the importance of occupational health education and the use of personal protective equipment and safe working conditions for construction workers.

Performance of Plain Concrete and Cement Blocks with Cement Partially Replaced by Cement Kiln Dust

The growth of the construction industry has led to the greater consumption of natural resources, which has a direct or indirect negative impact on the environment. To mitigate this, recycled or waste materials are being used as a partial substitute in the manufacture of concrete. Among these waste materials is cement kiln dust (CKD), which is produced during cement production. This study investigated the potential benefits of replacing part of the cement with CKD in two construction applications, i.e., plain concrete and cement blocks. This reflects positively on cost, energy, and the environment, since putting CKD in a landfill damages agricultural soil and plant respiration. In this study, an experimental program was carried out to study how replacing various percentages of ordinary portland cement (OPC) with CKD affected the compressive strengths, the tensile strengths, and the air contents of concrete and cement blocks. Although the results showed that the compressive and tensile strengths decreased as the amount of CKD increased, the air content of the concrete increased, which showed that 5% CKD was suitable for such applications. The results were used to propose two equations that approximate the concrete and cement block compressive strengths according to the CKD replacement percentage.

From hazardous asbestos containing wastes (ACW) to new secondary raw material through a new sustainable inertization process: A multimethodological mineralogical study

Nowadays, asbestos-containing wastes (ACW) still represent an important environmental problem and a severe health hazard due to the well known pulmonary diseases derived from asbestos fibers inhalation. Except for a very few cases, ACW are currently confined in controlled landfills, giving rise to increasingly high amounts of still hazardous wastes. A promising alternative to landfill confinement is represented by ACW inertization, but the high cost of the inertization processes so far proposed by the scientific community have hampered the creation of actually operative plants. In this paper, we explore the possibility to use an innovative process that ensures the obtainment of asbestos-free inert material in an exceptionally short processing time, thus greatly reducing cost-related problems. The efficacy of the inertization process has been verified through accurate mineralogical investigations on both chrysotile and crocidolite de-activated fibers, through X-ray diffraction, scanning and transmission electron microscopy. Overall mineralogical, microstructural and granulometric characteristics of the inert bulk material suggest that it could be successfully re-used as a secondary raw material in ceramic industries. This innovative inertization procedure could therefore provide an effective and economically sustainable solution for ACW management.

Consequences of cement dust exposure on pulmonary function in cement factory workers

BACKGROUND

Several health conditions are associated with cement dust exposure; obstructive and restrictive lung disorders are the most common consequences. The aims of this study were to assess the pulmonary function of cement factory workers and to determine the distribution of respiratory consequences resulting from dust inhalation.

METHODS

A cross-sectional study with convenience sampling was undertaken from December 2019 to March 2020. A total of 97 (response rate, 92.4%) nonsmoking male cement workers were recruited and compared with 97 apparently healthy volunteers. A spirometer was used to measure forced vital capacity (FVC), forced expiratory volume in one second (FEV₁ ), and their ratio (FEV₁ /FVC). The measured parameters were interpreted according to American Thoracic Society/European Respiratory Society guidelines.

RESULTS

Significant reductions were observed in pulmonary function parameters of cement factory workers compared to controls (FVC 4.03 vs. 4.65 L in controls; FEV₁ 3.06 vs. 3.95 L in controls; p < 0.001 for both comparisons). A significant variation was observed in the prevalence of spirometric patterns between the two participating groups. Ninety (92.8%) controls had normal respiratory function with no defects, compared with only 25 (25.8%) of the cement workers. Restriction was the most common respiratory problem, with a greater prevalence in the cement workers (44 [45.4%]) compared to six (6.2%) controls.

CONCLUSIONS

Cement factory workers showed decreased lung function and abnormal spirometric patterns which we attribute to dust inhalation. These workers should have periodic medical examinations and regular rotations through different factory departments to minimize the pulmonary hazards of cement dust.

Indoor Air Pollution with Fine Particles and Implications for Workers’ Health in Dental Offices: A Brief Review

(1) Background: Indoor air pollution can affect the well-being and health of humans. Sources of indoor pollution with particulate matter (PM) are outdoor particles and indoor causes, such as construction materials, the use of cleaning products, air fresheners, heating, cooking, and smoking activities. In 2017, according to the Global Burden of Disease study, 1.6 million people died prematurely because of indoor air pollution. The health effects of outdoor exposure to PM have been the subject of both research and regulatory action, and indoor exposure to fine particles is gaining more and more attention as a potential source of adverse health effects. Moreover, in critical situations such as the current pandemic crisis, to protect the health of the population, patients, and staff in all areas of society (particularly in indoor environments, where there are vulnerable groups, such as people who have pre-existing lung conditions, patients, elderly people, and healthcare professionals such as dental practitioners), there is an urgent need to improve long- and short-term health. Exposure to aerosols and splatter contaminated with bacteria, viruses, and blood produced during dental procedures performed on patients rarely leads to the transmission of infectious agents between patients and dental health care staff if infection prevention procedures are strictly followed. On the other hand, in the current circumstances of the pandemic crisis, dental practitioners could have an occupational risk of acquiring coronavirus disease as they may treat asymptomatic and minimally symptomatic patients. Consequently, an increased risk of SARS-CoV-2 infection could occur in dental offices, both for staff that provide dental healthcare and for other patients, considering that many dental procedures produce droplets and dental aerosols, which carry an infectious virus such as SARS-CoV-2. (2) Types of studies reviewed and applied methodology: The current work provides a critical review and evaluation, as well as perspectives concerning previous studies on health risks of indoor exposure to PM in dental offices. The authors reviewed representative dental medicine literature focused on sources of indoor PM10 and PM2.5 (particles for which the aerodynamic diameter size is respectively less than 10 and 2.5 μm) in indoor spaces (paying specific attention to dental offices) and their characteristics and toxicological effects in indoor microenvironments. The authors also reviewed representative studies on relations between the indoor air quality and harmful effects, as well as studies on possible indoor viral infections acquired through airborne and droplet transmission. The method employed for the research illustrated in the current paper involved a desk study of documents and records relating to occupational health problems among dental health care providers. In this way, it obtained background information on both the main potential hazards in dentistry and infection risks from aerosol transmission within dental offices. Reviewing this kind of information, especially that relating to bioaerosols, is critical for minimizing the risk to dental staff and patients, particularly when new recommendations for COVID-19 risk reduction for the dental health professional community and patients attending dental clinics are strongly needed. (3) Results: The investigated studies and reports obtained from the medical literature showed that, even if there are a wide number of studies on indoor human exposure to fine particles and health effects, more deep research and specific studies on indoor air pollution with fine particles and implications for workers’ health in dental offices are needed. As dental practices are at a higher risk for hazardous indoor air because of exposure to chemicals and microbes, the occupational exposures and diseases must be addressed, with special attention being paid to the dental staff. The literature also documents that exposure to fine particles in dental offices can be minimized by putting prevention into practice (personal protection barriers such as masks, gloves, and safety eyeglasses) and also keeping indoor air clean (e.g., high-volume evacuation, the use of an air-room-cleaning system with high-efficiency particulate filters, and regularly maintaining the air-conditioning and ventilation systems). These kinds of considerations are extremely important as the impact of indoor pollution on human health is no longer an individual issue, with its connections representing a future part of sustainability which is currently being redefined. These kinds of considerations are extremely important, and the authors believe that a better situation in dentistry needs to be developed, with researchers in materials and dental health trying to understand and explain the impact of indoor pollution on human health.

Biomass energy, particulate matter (PM2.5), and the prevalence of chronic obstructive pulmonary disease (COPD) among Congolese women living near of a cement plant, in Kongo Central Province

This study investigated whether the individual and combined effects of using biomass energy and living in the neighborhood of a cement plant were associated with the risk of COPD and respiratory symptoms among Congolese women. A total of 235 women from two neighborhood communities of a cement plant participated in this cross-sectional study. Participants were classified into the more exposed group (MEG = 137) and a less exposed group (LEG = 98), as well as into biomass users (wood = 85, charcoal = 49) or electricity users (101 participants). Participants completed a questionnaire including respiratory symptoms, sociodemographic factors, medical history, lifestyle, and household characteristics. In addition to spirometry performance, outdoor PM_2.5 (μg/m³) was measured. Afternoon outdoor PM_2.5 concentration was significantly higher in MEG than LEG (48.8 (2.5) μg/m³ vs 42.5 (1.5) μg/m³). Compared to electricity users, wood users (aOR: 2.6, 95%CI 1.7; 5.9) and charcoal users (aOR: 2.9, 95%CI 1.4; 10.7) were at risk of developing airflow obstruction. Combined effects of biomass use and living in the neighborhood of a cement plant increased the risk of COPD in both wood users (aOR: 4, 95%CI 1.3; 12.2) and charcoal users (aOR: 3.1, 95%CI 1.7; 11.4). Exposure to biomass energy is associated with an increased risk of COPD. In addition, combined exposure to biomass and living near a cement plant had additive effects on COPD.

Dust exposure risk from stone crushing to workers and locally grown plant species in Quetta, Pakistan

The aim of this study was to assess the effects of stone crushing dust pollution on three commonly cultivated fruit plant species (Vitis vinifera L., Morus alba L., and Prunus armeniaca L.) and on the health of workers working at crushing plants. The trial was carried out on fruit plant species grown close to the stone crushing units located near the northwestern (Brewery) bypass of Quetta city, Pakistan, near National Highway NH-25. Plant materials were collected from three polluted sites at a distance of 500, 1000, and 1500 m, respectively, away from the stone crushing units and one locality of comparatively clean air considered a control at 4000 m away from these crushing components. To know the status of air disorder near the experimental sites, the suspended particulate matters and both oxides of sulfur and nitrogen were also noted during operating hours. Consequences of the study indicated that during the crushing process, a fine aerosol of stone dust is often generated which could cause a significant health hazard to workers and also affect plant productivity due to the smothering of plant stomata. Environmental data designated that the average highest evaluated total suspended particulate matter (TSPM), NO_x, and SO_x were 7400 μg/m³, 803.7 μg/m³, and 216 μg/m³, respectively, at 500-m distance which gradually decreases as the distance increases-all of these pose a health risk to operators. The maximum deposit dust washed from the plant leaf surface under study was found to be 8.2, 4.6, and 4.4 at the distance of 500 m in all the investigated plant species which was highly significantly higher than that of the control site (4000 m). Among the plant species, the maximum dust fall was noted on the leaves of Vitis vinifera L., and minimum was on the leaves of Prunus armeniaca. The locations affected by more stone dust pollution (500 m) were leading to a reduction in the yield and quality of fruits. The studied stone crushing units had high percentages of closed stomata both on the upper sides (Us) and lower sides (Ls) of leaves at 500-m distance from stone crushing installations. Data regarding workers' health indicated the maximum age distribution among the workers was between the age groups of 20-35 years (46.15%). Results also showed that stone crushing workers suffered from symptoms of respiratory diseases (82.17%), allergies (72.13%), headaches (75.09%), coughing (78.36%), and tiredness (92.31%).