Dust Levels Research Articles

Metal biomonitoring using fractioned dust to investigate urinary and oxidative stress biomarkers among occupationally exposed chromite mine workers.

Exposure to heavy metals has been associated with the generation of reactive oxygen species (ROS) among exposed individuals in occupational and environmental settings. Dust is considered a significant contributor to airborne metal exposure, and previous data suggest that their levels in dust may vary based on its particle sizes. However, no biomonitoring study has been reported so far to address the metal-induced oxidative stress using different dust fractions, particularly in occupational settings. We designed a systematic cross-sectional study involving 110 chromite mine workers stratified into loaders (n = 28), extractors (n = 47) and operators (n = 35), and controls (n = 30) to find out the association between dust-bound metal exposure and oxidative stress using urinary creatinine-adjusted metal level as a biomarker of metal exposure. Results suggested elevated urinary levels of Cr 51.34 ± 8.6 along with Pb 34.29 ± 4.39, Cd 21.1 ± 2.6, and Ni 18.98 ± 3.01µg/g creatinine in exposed (extractor group) workers. Correlating metal levels with oxidative stress revealed elevated malondialdehyde (MDA) levels of 62.28 ± 5.52nM/dl among the extractors showing high levels of lipid peroxidation. Furthermore, blood superoxide dismutase (SOD) was also found significantly correlated (P = 0.000) with urinary toxic metal levels among exposed workers. We report the association between metal exposure and oxidative stress in exposed mining workers that may give rise to workers' susceptibility towards genetic and non-genetic health implications. The current study emphasized on the need for exposure control measures in the chromite ore mining activity areas.

Perancangan Sistem Monitoring Parameter Kualitas Udara (Suhu, CO, LPG dan Debu) berbasis IOT

Research has been carried out on the design of a monitoring system for air quality parameters (temperature, CO, LPG and dust) whose data is integrated in real time. The measuring instrument uses the Arduino Uno R3 microcontroller base. The MQ-9 and MQ-5 gas sensors are used to measure air pollution, while the LM35 and DSM 501A sensors are used for temperature and dust. This system is also connected with Xbee S2 as a data sender and receiver based on WIFI. The voltage source is connected to a 10 W solar panel which is regulated by the charger controller so that when the battery is full, the battery charging connection will be disconnected. The software used is Arduino IDE 1.8.1 and X-CTU. The data that can be measured by the tool is the level of air pollution of CO and LPG gas, air temperature and PM 2.5 particulates in the air. The measurement phase was tested with samples of gas (CO and LPG) as well as a heat source and a cold source for temperature. The test data shows that all sensors are able to detect the presence of CO and LPG gas, temperature differences and dust levels in the air and then display the data in real time.

Association of egg protein levels in dust with allergy status and related factors.

Levels of peanut protein in dust have been reported to be associated with sensitization and allergy to it, so controlling food protein in dust may help prevent food allergy. However, studies of factors associated with egg protein levels in dust are scarce. This study aimed to determine the factors contributing to egg protein levels in dust. This cross-sectional study included 159 participants in the Sub-Cohort Study of the Japan Environment and Children's Study in Yamanashi Prefecture at a 6 year follow up. House dust at 6 years was collected and egg protein concentrations were measured for whole egg protein. Household factors, including the maternal frequency of egg consumption, were assessed by questionnaires. A linear regression model was used to analyze the effect of household environmental factors on egg protein in dust. In multivariate analysis, frequent maternal egg consumption (≥5 times a week) was associated with higher egg protein concentrations in house dust (β= 0.96, P=0.01). The egg protein load was significantly associated with a higher number of cohabitants (≥5, β=0.85, P=0.02) in addition to frequent maternal egg consumption. Among the participants, 140 (88.1%) had no egg allergy, 15 (9.4%) were egg tolerant, and 4 (2.5%) had an egg allergy at 6 years old. There was no significant association between the current egg allergy status and egg protein concentrations in dust. The frequency of maternal egg consumption and the number of inhabitants are contributing factors to egg protein levels in dust.

Design & Development of MPPT Using PSO With Predefined Search Space Based on Fuzzy Fokker Planck Solution

Production of clean, green solar PV (SPV) power in developing countries now becomes a trend because of their economic and technical benefits. Therefore, generating maximum power out of the SPV is a key searchable area. The SPV must produce power at its terminal at their maximum possible power. To reach to the maximum possible power, maximum power point tracker is used in conjunction with SPV. Extracting maximum power from SPV under varying partial shading condition is one of the important factor in performance improvement of SPV. The characteristics of classical MPPT controller is not acceptable under variable shading condition. A clear distinction between global maxima power point from global minima using MPPT technique must be needed for extracting maximum power. This paper proposes a PO MPPT based particle swarm optimization with improved search space, optimised through Fuzzy Fokker Planck solution. The pre-defined search space has been introduced to provide fine tune to membership function used in Fuzzy logic controller. The partial shading performance has been examined under four different condition such as active partial shading, colour spectrum, dust level and GHG concentration. Both hardware and simulation studies has been carried out for the proposed techniques. The MATLAB simulation result and that of proposed MPPT, offer more and better performance in terms of algorithm convergence by enhancing the efficiency of system under varying shading condition.

Estimating Indoor Population Density from Non-contact

With the spread of Covid-19, it is important to comprehend the indoor environment. It is also important to estimate indoor population density in order to avoid three Cs: Closed space, Crowded places, and Close-contact settings. This paper proposes a system for estimating indoor population density based on indoor environment data through Wireless Sensor Network (WSN). The proposed system collects indoor environment such as temperature, humidity, illuminace, CO2 concentration, and dust level. Then, the proposed system estimates indoor population density from collected environment data. The proposed system estimates the indoor population density from indoor environment data by machine learning. This study also investigates whether sensor data are adequate for estimating indoor population density. The experimental results show that the proposed system achieves about 80 % or more estimation accuracy by using multiple types of sensors, thereby demonstrating the effectiveness of the proposed system. The proposed system is expected to measure the closed space also estimate crowded rooms, which is a helpful finding for preventing the spread of COVID-19.

Initial assessment of imports of chlorinated paraffins into Nigeria and the need of improvement of the Stockholm and Rotterdam Conventions

Short-chain and medium-chain chlorinated paraffins (SCCPs/MCCPs) are of concern due to their persistence, bioaccumulation, and toxicity. SCCPs were listed in 2017 as persistent organic pollutants (POPs) in the Stockholm Convention and Rotterdam Convention for Prior Informed Consent (PIC) procedure. MCCPs are evaluated in the POPs Reviewing Committee for listing. Studies in Africa demonstrate high SCCP/MCCP levels in house dust and human milk. Therefore, this study undertook an initial assessment of the production and import situation in Nigeria. The Nigerian government has not assessed SCCPs yet and has no registered exemptions for SCCPs and therefore should not produce or use SCCPs. Also, Nigeria has not notified Rotterdam Convention of PIC procedure and, therefore, no SCCP should be imported into Nigeria. Since no local production of SCCPs/MCCPs was observed in Nigeria, this study therefore compiled data on importation of SCCPs/MCCPs and products which may likely contain these chemicals from the UN Comtrade Database for the period 1996 to 2018. Despite the listing of SCCPs in the Rotterdam Convention, there is still no specific Harmonized System (HS) codes for SCCPs/MCCPs. This study therefore used HS codes of product categories known to contain SCCPs/MCCPs. HS substance categories under which SCCP/MCCPs are usually imported include plasticisers and other product categories that amounted to 229,779 and 518,342 tonnes respectively but without specific information on the type of plasticiser. About 39% of PVC and rubber imports of 2,683,015 tonnes and 3,516,052 tonnes respectively contain plasticisers. Based on the SCCP and MCCP impact factors from literature for China, the highest amount of SCCP (33,712 tonnes) was imported in the different PVC products while rubber products accounted to 1386 tonnes and PUR foam to 2331 tonnes. The amount of imported MCCPs in PVC products (25,599 tonnes) and rubber products (32,317 tonnes) was in the same order of magnitude while MCCP imported in PUR foam was estimated to 2020 tonnes. At the end of life (EoL), these product categories most likely contain appreciable amount of SCCPs possibly above Basel Convention low POP limit. This will hamper recycling and circular economy for these waste categories and generate POPs stockpiles/wastes that are difficult to manage/destroy in Africa. Hence there is an urgent need for specific HS Codes for SCCPs and industrial POPs currently produced/used for better control. Presently, products containing SCCPs are not labelled and are imported in huge quantities into Nigeria, without monitoring. In its current form this rather conveys a pseudo-safety for industrial POPs that do not exist. The Rotterdam Convention needs to establish specific HS codes for POPs for an appropriate PIC procedure and effective control of industrial POPs still produced. Furthermore, products containing SCCPs (and other POPs) require labelling and should also be covered under the Rotterdam Convention. The study highlights that Nigeria should urgently update the NIP for chemicals listed from 2015 to 2019 with a detailed SCCP inventory and develop monitoring capacity for market surveys. The Rotterdam Convention does not function fully and need to significantly improve to assure PIC procedure.

Polybrominated Dibenzo-p-dioxins/Furans (PBDD/Fs) and Diphenyl Ethers (PBDEs) in the Indoor and Outdoor of Gymnasiums

It is still unknown whether the organobromine compounds in the indoor environment of the gyms would affect human health. This study tried to investigate PM2.5 and indoor-dust levels of polybrominated dibenzo-p-dioxins/furans (PBDD/Fs) and diphenyl ethers (PBDEs) in the gyms and then to further assess the health risks of the gym users and employees who were exposed to these organobromines through inhalation and ingestion. The gyms were to be examined for PBDD/DF/DEs on PM2.5 indoors and outdoors and in indoor dust. The results showed that indoor-dust, indoor PM2.5, and outdoor PM2.5 levels of PBDD/Fs were 37.8 ± 13.7 pg WHO2005-TEQ g-1 and 0.00650 ± 0.00340 and 0.00469 ± 0.00101 pg WHO2005-TEQ m-3, respectively, in the gyms, while for PBDEs, they were 2670 ± 2330 ng g-1 and 9.54 ± 4.68, and 8.27 ± 3.46 pg m-3. The PBDEs levels observed in this study were relatively lower when compared with the current global data of PM2.5 and indoor dust levels of PBDEs. The observed PM2.5-bound PBDDFs and PBDEs in the indoor gyms were not related to those in the outdoor gyms, but certain PBDE level was associated with PBDD/Fs in the indoor dust of the gyms. It suggested that the outdoor emission might not be correlated with the indoor emission, whereas indoor-dust PBDD/Fs might be converted from the pyrolysis of indoor-dust PBDEs. To assess the risks, the non-dietary daily intakes of PBDEs and PBDD/Fs were estimated as 1.61-2.11 × 10-7 and 4.15-5.42 × 10-13 mg kg b.w.-1 day-1, respectively, in the employees and 5.04-6.58 × 10-8 and 1.29-1.69 ×10-13 mg kg b.w.-1 day-1, respectively, in the gym users. The values didn’t exceed the critical levels when the gym employees and users were assessed by non-cancer and cancer risks of organobromines. In conclusion, although the gym employees and users inhaled more PM2.5 during the exercise, the risks of PBDD/DE/DFs were still under the acceptable levels.

Environmental Health Risk Analysis of Dust Exposure on Employees in PT. Cassia Co-op Indonesia in Jambi

The dust has a negative impact that can affect workers’ health. This study aimed to analyze the environmental health risks of dust exposure on workers at PT. Cassia Co-op Indonesia in Jambi. Descriptive quantitative research was conducted using an Analisis Risiko Kesehatan Lingkungan (ARKL) approach, including analysis of hazard identification, dose-response, exposure assessment, and risk characteristics. 61 respondents from the production division were selected as samples with a disproportionate stratified random technique. Data was collected using a questionnaire and Total Suspended Particulate (TSP) concentration from company’s secondary data. The results of measuring dust levels at 2 (two) points obtained a concentration value that was still below the threshold, but 77% of respondents experienced health problems related to TSP dust. The real-time intake value of TSP exposure of workers was not at risk of health problems (RQ<1) at both measurement points, and the intake lifespan value of TSP exposure was at risk of health problems (RQ>1) for all workers in the 15th year at point 1. It is recommended for companies to conduct regular health checks on workers, provide PPE and apply the standard use of PPE, make rules that prohibit smoking while working, and increase the location and frequency of testing for TSP dust levels in the company.

Air Pollution Associated with Total Suspended Particulate and Particulate Matter in Cement Grinding Plant in Vietnam

Air pollution associated with suspended particles has become a significant concern in Vietnam recently. The study aimed to (1) investigate dust sources; (2) measure concentration levels of Total Suspended Particulate (TSP), Particulate Matter (PM) fractions; (3) identify silica levels and the correlation with respirable particles at a cement grinding plant in Vietnam. A total of 312 samples (52 TSP, 160 PMs) at 13 processes were measured using the direct-reading dust meter. The silica composition was analyzed in a certified laboratory using the X-ray fluorescence (XRF) technique. SPSS version 26 for Window was used to analyze the data. The operations of the cement grinding plant created multiple dust sources from the jetty to the cement dispatch process. The TSP levels ranged 0.06–38.24 mg m−3, and 40.38% (n = 21) TSP samples exceeded the Permissible Exposure Limit (PEL) for an 8-h working shift. Besides that, there was a wide range and significant concentration levels of PMs in the cement processes. The levels of PMs were PM1 (0.00–0.06 mg m−3), PM2.5 (0.01–0.83 mg m−3), PM4 (0.02–4.59 mg m−3), PM7 (0.03–16.94 mg m−3), and PM10 (0.04–26.85 mg m−3). The highest mean levels of PMs factions were measured at the pre-grinding process. The inefficient operation of the dust collector contributed a significant factor to the dust dispersion in this process. The silica’s mean (SD) composition in respirable dust was 20.4% (0.86) and was not significantly different amongst the processes. There was a significant correlation between the levels of respirable dust and silica exposure in the cement grinding plant (r = 0.99). The improvement of indoor air quality is needed to prevent health effects on cement workers.

Ecophysiological response of Eucalyptus camaldulensis to dust and lead pollution

Background: Air and soil pollution are among the main concerns in urban areas worldwide, and dust and heavy metals are major contributors to environmental pollution. Lead (Pb) is a highly toxic heavy metal that badly affects human health as well as plant's survival and growth. Vegetation can play an important role in ameliorating the effects of these pollutants. Eucalyptus camaldulensis is well adapted and cultivated throughout a wide range of urban environments from temperate to tropical climates. Methods: A 90 days experiment was conducted to investigate the effects of lead (Pb) and dust pollution on the growth performance of young E. camaldulensis plants. Four months old seedlings were treated with a factorial combinations of Pb (0,10 and 20 mg/l applied in irrigation) and dust levels (0,5 and 10 g applied on foliage). Results: All morphological traits (root length, shoot length, stem diameter) and biomass (root and shoot, fresh and dry mass) of E. camaldulensis were significantly reduced when exposed to higher Pb and dust levels. The highest Pb treatments exhibited greater Pb accumulation in plant roots (23.54 ± 1.61 mg/kg), shoots (15.53 ± 1.98 mg/kg), and leaves (13.89 ± 1.49 mg/kg). Dust load on leaves was greater (72.78 ± 8.1 mg/cm2) for those treatments with higher dust and Pb additions compared to the control (16.11 ± 2.0 mg/cm2). Chlorophyll content was greater at the start of the experiment (68.78 ± 0.74 mg.g-1FW) and progressively decreased over time consistently with the increase of Pb and dust levels applied. Conclusions: The results of the experiment, suggest that E. camaldulensis could be successfully grown in minimum to moderate Pb and dust polluted urban environments.

Breathing exercise dan penggunaan masker sebagai terapi dalam meningkatkan kapasitas vital paru pada pekerja

Background: High levels of dust in the air can affect lung function, to prevent the occurrence of diseases of the lungs caused by dust exposure, it is necessary to use a mask at work and in an effort to increase the lung's vital capacity due to exposure to dust at work can be done with breathing exercises (Breathing) Exercise) and is expected to improve lung ventilation function.Objective: The purpose of this study was to study the interaction of the application of breathing exercises and the use of masks to increase lung capacity.Methods: This research is a quasy experiment research with a complete random design in two directions. The treatments were tested in four groups namely, breathing exercise, the use of mask, breathing exercise and the use of masks and control groups.Results: The average vital lung capacity in the treatment group with the interaction of the use of masks and the application of breathing exercise is 4.3 L, in the group using the 3.0 L mask, in the group that does breathing exercise 3.1 L while in the control group that does not use masks and applying breathing exercises with an average capacity of 2.7L.Conclusion: Breathing exercises and the use of a mask for 1 month continuously can increase the vital capacity of the lungs.

Coal mine dust lung disease in miners killed in the Upper Big Branch disaster: a review of lung pathology and contemporary respirable dust levels in underground US coal mines

ObjectivesIn 2010, 29 coal miners died due to an explosion at the Upper Big Branch (UBB) mine in West Virginia, USA. Autopsy examinations of 24 individuals with evaluable lung tissue...

Solar and sand: Dust deposit mitigation in the desert for PV arrays

Solar photovoltaic installations have now become a common sight across the globe. However, in places with a high level of dust, the panels have not performed as expected. The dust deposition acts to reduce the effective light that the solar cells receive thus reducing the output. As such, cleaning regimes are instituted to improve the performance of the panels. The more often the cleaning, the better the performance, but this could likely imply more energy is used for cleaning and the improvement may not be sufficient. In this paper, we develop a model to forecast the output power with respect to variables of cleaning, wind, humidity and temperature. The result shows that it is possible to develop a model to optimise cleaning regimes taking into account meteorological factors. One has to consider the impact of wind, which was found to be positively correlated with photovoltaic power output.

Comet fragmentation as a source of the zodiacal cloud

ABSTRACT Models of the zodiacal cloud’s thermal emission and sporadic meteoroids suggest Jupiter-family comets (JFCs) as the dominant source of interplanetary dust. However, comet sublimation is insufficient to sustain the quantity of dust presently in the inner Solar system, suggesting that spontaneous disruptions of JFCs may supply the zodiacal cloud. We present a model for the dust produced in comet fragmentations and its evolution. Using results from dynamical simulations, the model follows individual comets drawn from a size distribution as they evolve and undergo recurrent splitting events. The resulting dust is followed with a kinetic model which accounts for the effects of collisional evolution, Poynting–Robertson drag, and radiation pressure. This allows to model the evolution of both the size distribution and radial profile of dust, and we demonstrate the importance of including collisions (both as a source and sink of dust) in zodiacal cloud models. With physically motivated free parameters this model provides a good fit to zodiacal cloud observables, supporting comet fragmentation as the plausibly dominant dust source. The model implies that dust in the present zodiacal cloud likely originated primarily from disruptions of ∼50-km comets, since larger comets are ejected before losing all their mass. Thus much of the dust seen today was likely deposited as larger grains ∼0.1 Myr in the past. The model also finds the dust level to vary stochastically; e.g. every ∼50 Myr large (>100 km) comets with long dynamical lifetimes inside Jupiter cause dust spikes with order of magnitude increases in zodiacal light brightness lasting ∼1 Myr. If exozodiacal dust is cometary in origin, our model suggests it should be similarly variable.

Literature Review: Risk Factors for Lung Physiological Disorders Due to Exposure to Wood Dust

Introduction: The wood processing industry in Indonesia is experiencing very rapid development, so there are positive and negative impacts of this industry for the country. The positive impacts that occur such as increased economic growth while the negative impacts that occur include environmental pollution which directly impacts the health of workers. One of the bad effects experienced by workers working in the industrial sector is wood dust. Wood dust is an invisible object that can circulate through the air so that it can enter the body and cause disruption of lung function of workers. The purpose of this research to conduct research on the factors of lung physiology disorders caused by vulnerability to wood dust. Method: The method was used in this research is a literature review by reviewing 10 relevant articles. Results: The effects showed that the method used is the same, which is using cross sectional, and during the study the data collection tools used questionnaires with interviews. In line with the outcomes of the study, factors for pulmonary physiology are not only caused by dust levels that exceeded the threshold value (NAV), but there are several other factors, namely individual characteristics such as length of service, duration of exposure, smoking habits, and use of personal protective equipment (PPE). Moreover, several studies presented bivariate tests to find out the relationship between variables that are factors in the occurrence of pulmonary physiology. Conclusions: Of 10 studies most have performed a bivariate analysis, but just a few have analyzed all the factors causing pulmonary physiology. Keywords: literature review, pulmonary physiology, risk factor, wood dust

Многофункциональная система безопасности угольных шахт – визуализация событий (горнотехнических процессов) с рабочего места шахтера

The paper reviews the use of mobile video monitoring equipment in coal mines. The most common option is the use of stationary video cameras with real-time video streaming to the mine dispatcher's control monitor via cables. Despite all the benefits of the information obtained, this method has certain limitations due to the specific features of the mine atmosphere, i.e. high humidity and dust levels, as well as the impossibility to organize video monitoring over the entire length of the mine workings. Therefore, mobile video monitoring equipment, both portable and vehicle-based, is efficient supplement to the stationary video cameras. The portable devices include smart phones and the battery-powered head lights with an integrated video camera, which have recently become very popular. In both cases, an important consideration, in addition to the actual video capturing, is the issue of transmitting video data to the top level, i.e. to the mine dispatcher's control panel. The following options are possible: connection to the mine wireless network hotspots via radio channel, reading the information in the lamp rooms when leaving the mine and real-time broadcasting from the mine to the top level. The assumption is made that in order to implement the fastest (and the most efficient) way that works without delays between capturing and transmitting of video data to the daylight surface, such as the latter of the options above, a communications infrastructure based on wireless and cable networks needs to be deployed in the mine workings. The required infrastructure is present in a number of systems designed to locate miners inside the mine workings as part of a multifunctional security system, which enables continuous radio communication of individual devices with infrastructure nodes and, therefore, real-time video data transmission.

Pelletization of torrefied palm kernel shell by using different binding agents

Palm kernel shell (PKS) pellets are used as fuel for boilers due to their uniform shape and carbon content. However, the pellet's low mechanical properties can cause a high level of dust, increased fire explosions, and become health hazards to workers, which become challenging during transportation and storage. In this study, four types of binders, carboxymethylcellulose, lignin, starch, and glycerol, were used to improve the mechanical durability of torrefied PKS pellet. The PKS was torrefied at 250 ℃ for 30 min and pelletized at 130 ℃ and 12 MPa. The torrefied pellets were characterized according to their chemical and physical properties. Results indicate that the density of pellets using all binders achieved more than the standard value (600 kg/m3). Overall, the carboxymethylcellulose could be used as a suitable binder that gives the highest mechanical durability (4449 N), low ash content (4.2 wt%), and improved HHV (20.68 MJ/kg) compared to other binders for torrefied PKS pellets to be used as fuel for power generation.

Occupational exposure to crystalline silica in artificial stone processing

Respirable Crystalline Silica (RCS) is a hazardous substance with known effects that can be well correlated with exposure levels that still persist in many traditional sectors, such as construction or stone processing. In the past decade, exposure scenarios for RCS have been found in the sector of artificial stone processing. The aim of this study is to evaluate the levels of RCS in facilities specialized in the production of artificial stone countertops and other accessories for the furnishing of kitchens, bathrooms, and offices after the introduction of some preventive technical measures such as wet processing or local exhaust ventilation systems. The study involved 51 subjects in four facilities. Personal silica exposure assessment was carried out using GS3 cyclones positioned in the breathing zone during the work shift. Quantitative determination of silica was carried out by X-ray diffraction analysis. Respirable dust levels were in the range 0.046–1.154 mg/m3 with RCS levels within the range <0.003-0.098 mg/m3. The highest exposure was found in dry finishing operations. Although there was a remarkable reduction in RCS exposure levels compared to what was observed in the past before the introduction of preventive measures, the data still showed hazardous exposure levels for some of the monitored activities.

Tuberculosis and Silicosis Burden in Artisanal and Small-Scale Gold Miners in a Large Occupational Health Outreach Programme in Zimbabwe.

Artisanal and small-scale miners (ASMs) labour under archaic working conditions and are exposed to high levels of silica dust. Exposure to silica dust has been associated with an increased risk of tuberculosis and silicosis. ASMs are highly mobile and operate in remote areas with near absent access to health services. The main purpose of this study was to evaluate the prevalence of tuberculosis, silicosis and silico-tuberculosis among ASMs in Zimbabwe. A cross-sectional study was conducted from 1 October to 31 January 2021 on a convenient sample of 514 self-selected ASMs. We report the results from among those ASMs who attended an outreach medical facility and an occupational health clinic. Data were collected from clinical records using a precoded data proforma. Data variables included demographic (age, sex), clinical details (HIV status, GeneXpert results, outcomes of chest radiographs, history of tuberculosis) and perceived exposure to mine dust. Of the 464 miners screened for silicosis, 52 (11.2%) were diagnosed with silicosis, while 17 (4.0%) of 422 ASMs were diagnosed with tuberculosis (TB). Of the 373 ASMs tested for HIV, 90 (23.5%) were sero-positive. An HIV infection was associated with a diagnosis of silicosis. There is need for a comprehensive occupational health service package, including TB and silicosis surveillance, for ASMs in Zimbabwe. These are preliminary and limited findings, needing confirmation by more comprehensive studies.

A study on stress factors in ferrous metallurgy in Bulgaria and ways of their minimizing and control

Abstract Background Stress at workplace arises when the requirements for workers don't meet their personal or social capabilities, or differ from the individual's needs and motivation. Occupational stress is observed in a number of both elementary and high-tech occupational fields. In ferrous metallurgy it could be associated with 24/7 operating mode, high work intensity and a variety of unfavorable characteristics of working environment. The aim of the study is to clarify the nature of factors - stressors in ferrous metallurgy and to define ways for reduction of their negative health impact. Materials and Methods Study subject are 91 workers in an electric steel-making department of a ferrous metallurgy enterprise in Bulgaria. Data, concerning working conditions, work characteristics, workers satisfaction, presence/absence of stress and chronic diseases, were collected by direct individual self-administered questionnaire and documents review. Results Two of three study subjects reported stress related to their work. Noise, varies from 89.2 to 92.2 dB/A (at rate 85 dB/A) in different sections of the workshop, is the biggest stressor according to 77.5% of the investigated people, followed by short deadlines for task performance (46.5%) and ineffective leadership (32.4%). In addition, negative effects of stress is increasing by high dust levels, reaching up to 7 mg/m3 air at a standard of 6 mg/m3 air, and contain manganese, coke, chamotte, free and bound silica, rare metals, increased concentration of CO and more.Nevertheless workers consider that the organization provides measures for stress reduction by strict control on the limit values of noise, dust, temperature and chemicals (49.2%),provision of personal protective equipment establishment (69%) of a rational mode of work and rest (56.3%) and healthy eating (47.9%). Conclusions Despite a plenty of environmental and organizational stressors, their negative effects could be decreased by appropriate preventive measures. Key messages Factors-stressor in ferrous metallurgy could be associated with a variety of unfavorable characteristics of working environment,non-stop operating mode, high work intensity and poor time management. Noise is the biggest stressor followed by short deadlines for task performance and ineffective leadership. Stressors are modifiable and preventable by strict hygienic control and improved management.