Dust Levels Research Articles

Analysis of dust and noise exposure levels in the mining industry from the national surveillance program in 2019

Objective: To understand the exposure level of dust and noise in the mining industry and provide data support for revising policy for the prevention and control of occupational diseases. Methods: In May 2022, Data was collected through the National Surveillance Program for Occupational Hazards in the Workplace. Descriptive analysis was conducted for dust and noise levels by industry type and enterprise size from 7, 679 enterprises in the mining industry among 29 provincial regions nationwide. Results: The enterprises in the mining industry included in the National Surveillance Program for Occupational Hazards in the Workplace are mainly small and micro, accounting for 47.97% (3684/7679) and 30.00% (230/7679) respectively. The industry is mainly compred of employers in the non-metallic ming and beneficiation industry, accounting for 50.25% (3859/7679). Among the enterprises with silica dust, coal dust, and noise hazards, the proportion of enterprises where total dust concentration and noise intensity exceed the standard is higher than 50%. 30% of the posts are with an exposure level of silica dust, coal dust, and noise that exceeds the standard. The exceedance rate and the median of the time-weighted average concentration of total coal dust among large and medium-sized enterprises are higher than those among small and micro-sized enterprises (P<0.05) . Conclusion: The dust and noise hazards in the mining industry are lower than in the past in China, but more than 25% of workers are still at a high risk of occupational pneumoconiosis and noise deafness. Therefore, intervention and surveillance strategies should be strengthened in the future.

IMPACT OF PARTICULATE MATTER 2.5 CONCENTRATION AND DENSITY TRICHOMES LEAF OF SHADE PLANTS ON PROTOCOL ROAD, SEBERANG ULU II DISTRICT, PALEMBANG CITY

An increase in the number of motorized vehicles has the potential to increase air pollution, es-pecially on protocol roads, one of which is Particulate matter (PM 2.5). The response of tri-chomes from shade plants to vehicle exhaust gases can be used as environmental biomonitor-ing. The main road in Seberang Ulu II District has a fairly dense mobility in terms of the Ve-hicle Volume Ratio to Road Capacity (VCR). The purpose of this study was to determine the relationship between particulate dust levels and the density of leaf trichomes of shade plants on the protocol road, Seberang Ulu II District, Palembang City. The method in this research is ex post facto with a laboratory approach. Determination of the plot of this study using purpos-ive sampling based on consideration of the circumstances surrounding the study. Plots 1 and 2 are on Jalan A. Yani, Plots 3 and 4 are on DI. Panjahitan Street and Plot 5 as a comparison plot are on Kapten Abdullah Street. The results in this study showed that the highest trichome density values were found in polluted areas.

Exposure levels of dust, endotoxin, and microorganisms in the Danish recycling industry.

Recycling of domestic waste and a number of employees in the recycling industry is expected to increase. This study aims to quantify current exposure levels of inhalable dust, endotoxin, and microorganisms and to identify determinants of exposure among recycling workers. This cross-sectional study included 170 full-shift measurements from 88 production workers and 14 administrative workers from 12 recycling companies in Denmark. The companies recycle domestic waste (sorting, shredding, and extracting materials from waste). We collected inhalable dust with personal samplers that were analysed for endotoxin (n = 170) and microorganisms (n = 101). Exposure levels of inhalable dust, endotoxin, and microorganisms and potential determinants of exposure were explored by mixed-effects models. The production workers were 7-fold or higher exposed to inhalable dust, endotoxin, bacteria, and fungi than the administrative workers. Among production workers recycling domestic waste, the geometric mean exposure level was 0.6 mg/m3 for inhalable dust, 10.7 endotoxin unit (EU)/m3 for endotoxin, 1.6 × 104 colony forming units (CFU)/m³ of bacteria, 4.4 × 104 CFU/m³ of fungi (25 °C), and 1.0 × 103 CFU/m³ of fungi (37 °C). Workers handling paper or cardboard had higher exposure levels than workers handling other waste fractions. The temperature did not affect exposure levels, although there was a tendency toward increased exposure to bacteria and fungi with higher temperatures. For inhalable dust and endotoxin, exposure levels during outdoor work were low compared to indoor work. For bacteria and fungi, indoor ventilation decreased exposure. The work task, waste fraction, temperature, location, mechanical ventilation, and the company size explained around half of the variance of levels of inhalable dust, endotoxin, bacteria, and fungi. The production workers of the Danish recycling industry participating in this study had higher exposure levels of inhalable dust, endotoxin, bacteria, and fungi than the administrative workers. Exposure levels of inhalable dust and endotoxin among recycling workers in Denmark were generally below established or suggested occupational exposure limits (OEL). However, 43% to 58% of the individual measurements of bacteria and fungi were above the suggested OEL. The waste fraction was the most influential determinant for exposure, and the highest exposure levels were seen during handling paper or cardboard. Future studies should examine the relationship between exposure levels and health effects among workers recycling domestic waste.

94 Reducing Exposure to Respirable Crystalline Silica in the Construction and Minerals Industry by Using Wearable Real Time Respirable Dust Monitors

Abstract Real time monitoring of respirable dust (as a surrogate for RCS) opens the opportunity to warn workers when entering work areas with increased dust levels to provide them the information to fit RPE properly or exit the area. However in the past, the adoption of such monitoring approaches has been limited due to the bulkiness and price of devices. This paper reflects on how the miniaturisation of Optical Particle Counters has enabled light weight (&amp;lt;150g) wearable devices to be developed which are convenient for workers in the construction and minerals industry to wear on all working days. It provides an overview of the Optical particle counter. its performance in measuring respirable dust and how it has been integrated into a battery powered ' DustCanary; wearable device. Due to its size and convenience the DustCanary provides protection to both those at first line risk due to the areas they work (eg stone cutters, plant operatives) who by wearing such can devices can help identify changes in performance of Local Exhaust Ventilation (LEV). or controls so that remedial action can be taken secondary risk on a plant who are not necessarily wearing RPE (such as delivery drivers) who can be warned when they enter an area where there are elevated respirable dust levels Case study data and examples will be shared.

90 Bioaerosol Exposure in Automated and Traditional Waste Sorting Plants

Abstract The waste management sector takes a central part in the transition towards circular economy and is subject to technological progress and the implementation of new work operations. Traditional waste collection and processing systems are characterized by numerous tasks that favour waste workers’ exposure to bioaerosols, whereas exposure in modern automated waste sorting plants remains elusive. Moreover, there is still a lack of health-risk based exposure limits for most components contained in bioaerosols. We investigated occupational exposure to bioaerosols in traditional and automated waste sorting plants. The results revealed significant differences in various exposure levels, such as total dust (GM automated: 0.34 mg/m3, GM manual: 0.66 mg/m3), endotoxins (GM automated: 51 EU/m3, GM manual: 32 EU/m3) and microorganisms between and within type of plant. An assessment of the composition of air-borne fungal particles (FESEM based immunodetection method) showed significantly increased levels of fungal spores at automated waste sorting plants (GM automated: 1.2 × 105 spores/m3, GM manual: 2.1 × 104 spores/m3). Elevated total dust levels and concentrations of submicronic fungal fragments were significantly correlated to the occurrence of symptoms of the extrathoracic region, such as congested nose, in exposed workers. The results of this study showed high variation in exposure levels between and within type of waste sorting plant, as well as seasonal variation for some parameters, such as total dust and endotoxins. This indicates that Norwegian waste workers are potentially exposed to high levels of dust and microorganisms that may cause adverse health effects in receptible individuals.

22 Evaluation of Occupational Exposure to Respirable Crystalline Silica in Processing of Artificial Stone

Abstract Introduction Clusters of silicosis cases related to the fabrication of quartz conglomerate products and accessories for the furnishing of kitchens and bathrooms are recently reported. The aim of this study was to evaluate the exposure to airborne respirable dust and crystalline silica (RCS) in a company specialized in the production of quartz conglomerates countertops and to investigate the effectiveness of introduced preventive measures (wet finishing, increasing of exhaust ventilation, closing in cabins some of the sanding and finishing operations). Materials and Methods The study was carried out on 51 workers involved in cutting and finishing operations in four facilities. Exposure to respirable dust was evaluated using GS3 cyclones positioned at the breathing zone level for the entire duration of the work shift. RCS content was measured by X-ray diffractometric analysis. Results and Discussion Respirable dust levels were in the range 0.046-1.154 mg/m3 (mean 0.160 mg/m3) with RCS levels within the range &amp;lt;0.003-0.098 mg/m3 (mean 0.022 mg/m3). All RCS levels were lower than the Italian OEL of 0.100 mg/m3 and the 22% above the more restrictive ACGIH-TLV of 0.025 mg/m3. Statistically higher levels were found in correspondence with finishing operations than in cut operations (p&amp;lt;0.05) and during dry operations than in wet (p=0.02). RCS levels were lower than those found in the past before the introduction of preventive technical measures where RCS levels were up to 0.744 mg/m3. Although there was a decisive reduction in exposure levels compared to what was observed in the past, the data still showed a risk condition for some activities. Board of the Italian Association of Industrial Hygienists (AIDII). Her scientific activity is documented by over 80 printed publications both as articles in Journals and contributions to National Congresses.

Unique inverse association between allergic rhinitis and periodontitis: a nationwide population-based study

The increase in fine dust levels in the atmosphere has been associated with a growth in the incidence of environmental diseases, including allergic rhinitis (AR). Nasal obstruction caused by AR can impact the conditions in the oral cavity. The aim of this study was to determine the association between AR and periodontitis in the Republic of Korea. This study was based on data from the Seventh Korea National Health and Nutrition Examination Survey (KNHANES VII-1, 2016), which was conducted by the Korea Centers for Disease Control and Prevention. The study included 6129 adults older than 19 years. Sociodemographic information and medical variables including history of treatment of periodontitis (HTP) reflecting diagnosis of periodontitis and diagnosis of diseases such as AR were extracted from the data. HTP and AR were reported for 22.81 ± 0.84% (weighted percentage ± standard error) and 15.32 ± 0.63% of the studied population, respectively. A diagnosis of AR was reported for 11.07 ± 1.28% of those with HTP and for 17.55 ± 1.84% of those without HTP. From these, it was inferred that the prevalence of HTP was 1.536-fold higher in the non-AR group than in their counterparts with AR. Significant association was found between AR and HTP among those aged ≤ 64 years and the odds ratio (OR) of AR group for HTP was 0.62 (95% confidence interval:0.44–0.87; P = 0.0057). From this result, it can be inferred that patients diagnosed AR have lower risk of periodontitis.

Metal-oxide inhalation induced fever - Immuntoxicological aspects of welding fumes.

Metal fume fever is a well-known occupational disease that arises from prolonged exposure to subtoxic levels of zinc oxide-containing fumes or dust. This review article aims to identify and examine the possible immunotoxicological effects of inhaled zinc oxide nanoparticles. The current most widely accepted pathomechanism for the development of the disease involves the formation of reactive oxygen species following the entry of zinc oxide particles into the alveolus resulting the release of pro-inflammatory cytokines by activation of the Nuclear Factor Kappa B transcriptional signal, thus evoking the symptoms. The role of metallothionein in inducing tolerance is believed to be a key factor in mitigating the development of metal fume fever. The other, poorly proven hypothetical route is that zinc-oxide particles bind to an undefined protein in the body as haptens to form an antigen and act as an allergen. After activation of the immune system, primary antibodies and immune complexes are developed and type 1. hypersensitivity reaction occurs, that can cause asthmatic dyspnoea, urticaria and angioedema. The development of tolerance is explained by the formation of secondary antibodies against primary antibodies. Oxidative stress and immunological processes cannot be completely separated from each other, as they can induce each other.

Mineralogical Study of Respirable Dust in Artisanal SmallScale Quarries of Misisi Compound, Lusaka, Zambia

Misisi compound in Lusaka is characterized by artisanal small scale quarrying activities which are often dusty in nature and prone to hazards. This study reports respirable dust concentration and the mineralogical composition of rocks in the workplace. Dust sampling was carried out with the help of gravimetric samplers at five quarries. Respirable dust samples were collected during digging, chiselling, crushing, and loading sites. The results of the sampled dust indicated high levels of respirable dust at all five quarry crushing sites. For example, based on Time Weighted Average (TWA), the respirable dust concentration at the crushing site was recorded as 12.75 mg/m3 at quarry#1 compared to the Maximum Allowable Concentration (MAC) of 5 mg/m3 of Occupational Safety and Health Administration (OSHA). The results of mineralogical testing and analyses revealed that marble was the common rock type that was being mined by most of the ASMs in the studied area. Based on the point count data analysis, marble contained 98% CaCO3 and 2% SiO2.

Occupational Bioaerosol Exposures Associated with Poultry Farming

ABSTRACT This study aimed to investigate occupational exposure to particulate dust, endotoxin, and (1–3)-β-D-glucan among workers involved in various poultry farming activities. A total of 298 personal samples were collected from randomly selected individuals from exposure groups based on distinct poultry farming activities comprising broiler farms, rearing, laying, hatchery, and catching activities. Aside from the inhalable particulate dust concentration that was determined, filter extracts were also analyzed for (1–3)-β-D-glucan and endotoxin using the endpoint Glucatell® and Limulus amoebocyte lysate (LAL) assays, respectively. Data were analyzed using STATA 12 and linear regression models developed. The mean (GM) dust particulate concentration was 11.04 mg/m3 (GSD = 3.87); 2298 endotoxin units (EU/m3) (GSD = 10.56) and 149 ng/m3 for (1–3)-β-D-glucan (GSD = 4.62). A modest positive correlation was observed between log-transformed endotoxin and (1–3)-β-D-glucan concentrations (Pearson r = 0.44, p < .001), whilst a moderate negative correlation was observed for inhalable dust particulate and (1–3)-β-D-glucan (Pearson r = −0.33, p < .001). However, there was a very poor correlation between inhalable dust and endotoxin (Pearson r = −0.02, p < .001). In the regression models, exposure group based on the nature of farming activity explained 50% of the variability in dust particulate and glucan levels. For dust particulate, rearing activities were significant predictors of higher dust levels compared to hatchery work, while rearing, laying, broiler and catching activities were significant predictors of higher endotoxin or glucan levels. Furthermore, working in a small broiler was a significant determinant of elevated glucan exposures. Farms using automated laying activities had significantly higher particulate levels compared to those using manual laying activities. This study revealed that workers engaged in poultry farming activities were exposed to significantly high levels of inhalable particulate dust, endotoxin, and (1–3)-β-D-glucan concentrations, posing an increased risk for adverse respiratory health effects in these farm workers.

Metal composition and contamination assessment of urban roadway dusts on the Abu Dhabi-Liwa Highway, UAE

The metal composition of road-deposited dust along the Abu Dhabi-Liwa Highway was investigated to provide insight into the contamination profile and levels of road dust. The average concentrations of metals decreased in the order Al (28668 ± 4631 mg/kg)&amp;gt; Fe (21461 ± 2594 mg/kg) &amp;gt; Mn (711.8 ± 76.3 mg/kg) &amp;gt; Zn (210.6 ± 51.6 mg/kg) &amp;gt; Cu (94.9 ± 15.8 mg/kg) &amp;gt; Pb (83.6 ± 5.3 mg/kg) &amp;gt; Cd (75.1 ± 1.6 mg/kg) &amp;gt; Co (62.6 ± 6.4 mg/kg) &amp;gt; As (4.7 ± 2.9 mg/kg) &amp;gt; Ni (0.10 ± 0.19 mg/kg) &amp;gt; Cr (0.08 ± 0.06 mg/kg). The spatial variations of metals suggest different sources and contributing factors for these metals, with most dust metals having mixed traffic and non-traffic origins. The contamination factor (CF) and enrichment factor (EF) showed identically the same order, Cd&amp;gt; Pb&amp;gt; As&amp;gt; Zn&amp;gt; Co&amp;gt; Cu&amp;gt; Mn&amp;gt; Ni&amp;gt; Cr, whereas the geoaccumulation index (Igeo) follows a slightly different ranking, Cd&amp;gt; Pb&amp;gt; Zn&amp;gt; Co&amp;gt; As&amp;gt; Cu&amp;gt; Mn&amp;gt; Ni&amp;gt; Cr. Based on EF and CF levels, roadway dusts are enriched in all metals, except for Ni and Cr. Similarly, the average Igeo values show differing rates of pollution for all metals except for Mn, Ni, and Cr. All pollution indicators suggest extreme pollution with Cd. The pollution loading index values showed sites 1–10 are generally polluted, while sampling sites from 11 to 19 are unpolluted with decreasing pollution loadings. Dusts collected from both sides of highway were higher in metal content than those obtained from the central reservation area. This may be due to the prevailing southeast wind direction, resuspension of road dust, and farmlands, among others. Soils bordering the highway showed high metal contents with potential consequences on the agricultural products.

Self-cleaning coatings for minimizing the impact of dust precipitation on the power production of solar cells utilizing mesoporous TiO2/SiO2 and ZnO/SiO2 films

The production of customized site-specific anti-soiling nanocoatings is needed for better utilization in dry parts of the world, with consideration of natural dust fallout in those regions. Kuwait's atmosphere carries airborne dust 70% of the year. Thus, designing anti-soiling nanocoatings for the arid region is necessary when dusty atmospheres are considered the norm. In this contribution, all solar cells were coated by SiO2, ZnO/SiO2, and TiO2/SiO2 films for self-cleaning applications and were tested in the summer period with the high level of dust and temperatures the current, voltage and power output was measured. We directly relate the coatings' performance to the electrical power output of the coated solar cells, which is considered among the few studies in this field. Influences of properties ZnO/SiO2 and TiO2/SiO2 films, such as the surface morphology, transparency, and water contact angles on the power production efficiency of solar cells, were systematically investigated. The three fabricated films showed a contact angle of about 70o agrees with the expected hydrophilicity behaviour. The thickness values of SiO2, TiO2/SiO2 and ZnO/SiO2 films were found to be ∼35, 205 and 240, respectively. Transmission values of the synthesized SiO2, TiO2/SiO2 and ZnO/SiO2 films were determined at about 97.95, 96.62 and 96.25%, respectively, suggesting that all synthesized films are highly transparent over the visible range. Solar cell samples were subjected to natural conditions for 30 days in the summer. The results indicated that the effect of dust on the power production efficiency for ZnO/SiO2 and TiO2/SiO2 coated PV cells was lower than the solar cells coated with SiO2 film concluded from the low power output of 0.16 Watt for this coating compared to 0.18 and 0.2 Watts for the other two coatings. The mesoporous ZnO/SiO2 and TiO2/SiO2 films not only significantly minimized the accumulation of dust on the PV cells but also boosted the power-generating efficiency. The average daily power output of around 0.2 Watt and the deviation values of the soiling ratios of about 5% showed that TiO2/SiO2 film was a durable coating against dust for the presented experiment time, while the ZnO/SiO2 film started as good, but showed deterioration after six days of the experiment with a deviation in SR value reached 15%. The TiO2/SiO2 nanocoating showed consistent behaviour with lower deviations for soiling ratio (SR) values and constant average power output for the solar cells concluding good durability in solar cells tests during harsh conditions in the summer, implying the excellent service life of solar cells.

The effects of atmospheric dust and solar radiation on the dayside ionosphere of Mars derived from 17 years of Mars Express radio science observations

This work combines 17 years of Mars Express radio science (MaRS) observations with proxies for insolation and local/global atmospheric dust to investigate the combined and individual effects on the dayside ionosphere of Mars from the top down to the ionospheric base.The increase in insolation from orbital apocenter to pericenter in combination with Mars‘ dust cycle causes an average rise of the whole photochemically dominated region of the dayside ionosphere, ranging from 13 km at the ionospheric base up to 22 km above the main peak during conditions without a global dust storm. The declining phase of the 2018 global dust storm was observed by MaRS on the southern hemisphere and close to pericenter. The observed lifting effect on the whole photochemically dominated region of the ionosphere from the increased insolation and the high local and global atmospheric dust levels exceeds that seen by MaRS from similar seasons during years without a global dust storm.The average ionospheric peak altitude at the subsolar point rises for increasing levels of local atmospheric dust until a maximum elevation is reached. This maximum depends on the available insolation at the top of the planetary atmosphere. Further increases of the local atmospheric dust levels do not lead to a further rise of the average ionospheric peak altitude in the investigated data set. This indicates a limit for the warming/expansion of the lower neutral atmosphere and the consecutive lifting of the ionosphere based on the available insolation and explains why regional dust storms can cause a similar lifting of the ionospheric main peak region as global dust storms.

Breathing Fresh Air in the City: Implementing Avenue Trees as a Sustainable Solution to Reduce Particulate Pollution in Urban Agglomerations.

The issue of air pollution from particulate matter (PM) is getting worse as more and more people move into urban areas around the globe. Due to the complexity and diversity of pollution sources, it has long been hard to rely on source control techniques to manage this issue. Due to the fact that urban trees may provide a variety of ecosystem services, there is an urgent need to investigate alternative strategies for dramatically improving air quality. PM has always been a significant concern due to its adverse effects on humans and the entire ecosystem. The severity of this issue has risen in the current global environmental context. Numerous studies on respiratory and other human disorders have revealed a statistical relationship between human exposure to outdoor levels of particles or dust and harmful health effects. These risks are undeniably close to industrial areas where these airborne, inhalable particles are produced. The combined and individual effects of the particle and gaseous contaminants on plants' general physiology can be detrimental. According to research, plant leaves, the primary receptors of PM pollution, can function as biological filters to remove significant amounts of particles from the atmosphere of urban areas. This study showed that vegetation could provide a promising green infrastructure (GI) for better air quality through the canopy and leaf-level processes, going beyond its traditional role as a passive target and sink for air pollutants. Opportunities exist for urban GI as a natural remedy for urban pollution caused by PMs.

Prevalence and Determinants of Avian Allergic Manifestation in a Selected Rural Population in Mysuru: A Cross-Sectional Survey.

Avian diseases should be known to people who raise birds as pets or for commercial purposes. Exposure to high levels of airborne dust and endotoxins is known to cause allergies. This study, therefore, intends to assess avian allergy and its associated factors among poultry workers and bird fanciers in urban Mysuru. A cross-sectional study was done over three months among 60 poultry workers and 60 bird fanciers in a selected rural population of the Mysuru district. The participants were selected by simple random sampling method and their data were obtained by interview method using a pre-tested semi-structured questionnaire. Chi-square test/Fisher's exact test was used to check the associations between the demographic variables' avian allergy. The survey revealed that 31.67% of poultry workers and 53.33% of bird fanciers had symptoms. The majority of the study participants were illiterate and were not using personal protective equipment (PPE) regularly. The results showed a significant association between education (P = 0.013) and the use of PPE (P = 0.020) with avian allergy. Observing the health hazards, 42.10% had respiratory problems, 42.10% had skin problems, and 26.31% had eye problems. Further, a significant association was also found between education and knowledge about diseases (P = 0.001). The avian allergy among the bird fanciers was higher when compared to poultry workers. It is necessary to organize routine counseling, awareness, and training programs about diseases and prevention strategies related to their work and living environments and keep them updated.

Early Results from GLASS-JWST. XVI. Discovering a Bluer z ∼ 4–7 Universe through UV Slopes

We use the GLASS-JWST Early Release Science NIRCam parallel observations to provide a first view of the UV continuum properties of NIRCam/F444W selected galaxies at 4 < z < 7. By combining multiwavelength NIRCam observations, we constrain the UV continuum slope for a sample of 401 galaxies with stringent quality controls. We find that >99% of the galaxies are blue star-forming galaxies with very low levels of dust (Av β ∼ 0.01 ± 0.33). We find no statistically significant correlation for UV slope with redshift or UV magnitude. However, we find that in general galaxies at higher redshifts and fainter UV magnitudes have steeper UV slopes. We find a statistically significant correlation for UV slope with stellar mass, with galaxies with higher stellar mass showing shallower UV slopes. Individual fits to some of our galaxies reach the bluest UV slopes of β ∼ −3.1 allowed by stellar population models used in this analysis. Therefore, it is likely that stellar population models with a higher amount of Lyman continuum leakage, active galactic nucleus effects, and/or Population III contributions are required to accurately reproduce the rest-UV and optical properties of some of our bluest galaxies. This dust-free early view confirms that our current cosmological understanding of gradual mass + dust buildup of galaxies with cosmic time is largely accurate to describe the ∼0.7–1.5 Gyr age window of the universe. The abundance of a large population of UV faint dust-poor systems may point to a dominance of low-mass galaxies at z > 6 playing a vital role in cosmic reionization.

Co-occurrence and distribution of organophosphate tri- and di-esters in dust and hand wipes from an e-waste dismantling plant in central China

Electronic waste (e-waste) dismantling facilities are a well-known source of emerging contaminants including organophosphate esters (OPEs). However, little information is available regarding the release characteristics and co-contaminations of tri- and di-esters. This study, therefore, investigated a broad range of tri- and di-OPEs in dust and hand wipe samples collected from an e-waste dismantling plant and homes as comparison. The median ∑tri-OPE and ∑di-OPE levels in dust and hand wipe samples were approximately 7- and 2-fold higher than those in the comparison group, respectively (p < 0.01). Triphenyl phosphate (median: 11,700 ng/g and 4640 ng/m2) and bis(2-ethylhexyl) phosphate (median: 5130 ng/g and 940 ng/m2) were the dominant components of tri- and di-OPEs, respectively. The combination of Spearman rank correlations and the determinations of molar concentration ratios of di-OPEs to tri- OPEs revealed that apart from the degradation of tri-OPEs, di-OPEs could originate from direct commercial application, or as impurities in tri-OPE formulas. Significant positive correlations (p < 0.05) were found for most tri- and di-OPE levels between the dust and hand wipes from dismantling workers, whereas this was not observed in those from the ordinary microenvironment. Our results provide robust evidence that e-waste dismantling activities contribute to OPEs contamination in the surroundings and further human exposure pathways and toxicokinetics are needed to be elucidated.

Risk Factor Analysis of Dust Exposure with Symptoms of Respiratory Disorder in Brick Industry Workers in Tegowanuh Sub-District, Kaloran District, Temanggung Regency

The brick industry has the potential to create a source of pollution in the form of dust which is harmful to the environment and workers health from the burning process. This study aims to determine the risk factors and analyze the relationship between dust exposure and symptoms of respiratory disorder in workers. This study used the total sampling technique to choose a sample of 75 participants for an observational study with a cross-sectional approach. The results showed that the average total dust particulate levels at 13 points was 1748.47 µg/Nm3 and the average inhaled dust content in 75 respondents of 4.56 mg/m3. The results of the analysis showed that the variables associated with symptoms of respiratory disorder were inhaled dust levels (p=0.023), working period (p=0.040), length of exposure (p=0.032), and use of personal protective equipment (p=0.015). Workers in the brick sector in Tegowanuh Sub-District may have respiratory symptoms more frequently depending on their exposure to amounts of inhaled dust, working period, exposure duration, and use of personal protective equipment. During the work process, it is advised to use personal protective equipment as a mask to prevent the onset of respiratory problems.

Exposure to respirable dust and factors associated with abnormal pulmonary function among stone diggers in Kayole quarries, Nairobi City County, Kenya

Background: In Kenya, the quarry industry suffers several constraints: some quarry workers get injured, others get chronic diseases, while some die. This study assessed occupational exposure to respirable dust and factors associated with abnormal pulmonary function among quarry stone diggers in Mihang’o and Matopeni quarries in Kayole Nairobi City County, Kenya. Methods: The study was done in Mihang’o and Matopeni quarries. An analytical cross-sectional design was used and a sample size of 165 respondents was taken. An interviewer administered semi structured questionnaire. Spirometry tests were done by a qualified technician to assess pulmonary function. Respirable dust levels were determined with the aid of a particle counter. Descriptive statistics like frequency, means were used to summarize data and results were presented in frequency tables and graphs. Chi square tests and logistic regression were done. T tests were done to compare the means of dust levels in the two quarries. Results: This study found the daily mean levels of PM2.5 and PM10 were higher than the levels recommended by WHO. The age of the respondents, presence of respiratory symptoms, years of work experience, nostril covering, and smoking were factors associated with abnormal pulmonary function at (p≤0.05). Conclusions: In conclusion, chronic exposure to quarry dust increases the risk of developing respiratory symptoms and abnormal pulmonary function. This study recommended that routine particulate matter monitoring should be done in Nairobi quarries to provide data that can inform decisions on air pollution control actions.

Spatial distribution of histamine in bed bug-infested homes

Histamine is a component of the bed bug aggregation pheromone. It was recently identified as an environmental contaminant in homes with active bed bug infestations, posing a potential health risk to humans via skin contact or inhalation. It remains unclear how histamine is distributed in homes and if histamine can become airborne. In the present study, histamine levels in household dust were quantified from multiple locations within bed bug infested and uninfested apartments. Bed bug population levels were quantified using both traps and visual counts. The amount of histamine detected varied significantly with respect to sampling location, with the highest concentration of histamine quantified from bedding material. Infestation severity did not have a significant effect on histamine quantified at any location. Our results indicate that the bedroom should be the primary focus of histamine mitigation efforts, although histamine can be found throughout the home. Histamine quantified from homes without active bed bug infestations suggests that histamine from previous infestations can persist following pest eradication. These findings highlight the importance of histamine as a potential insect allergen and will be important for the development of targeted mitigation strategies of bed bug histamine.