Inorganic Dust Research Articles

The Prevalence of Hilar Lymphadenopathy and Related Factors in Pneumoconiosis Patients of a University Hospital Occupational Diseases Polyclinic

Objective: Pneumoconiosis is a fatal, irreversible interstitial lung disease caused by various inorganic dust and chemicals. The disease is radiologically characterized by micronodules, pleural plaques, emphysema, mediastinal and hilar lymphadenopathies (HL). There are hypotheses that fibrotic lymph nodes increase the dust load of the lungs in patients with pneumoconiosis. Our aim is to determine the frequency of HL and related factors in pneumoconiosis patients admitted to our unit in the light of current data.
 Material and Methods: 76 patients diagnosed with pneumoconiosis who applied to our unit between November, 2015 and October, 2020 were retrospectively screened. Sociodemographic characteristics, radiological, laboratory and clinical findings were evaluated. The frequency of HL and related factors were analyzed.
 Results: We found the rate of HL as 29,3%. The average age was 43,78 ± 7,54. There was no significant age difference between patients with and without HL (44,41±8,90 / 43,34±6,93 p=0,578). All of the patients were male. As the ILO (International Labor Organization) category rose, we saw an increase in the number of HL. 59,1% of the patients with HL had at least one active complaint (dyspnea, cough or sputum). The most common complaint was dyspnea (50%). We found a statistically significant increase in NLR (Neutrophil to Lymphocyte Ratio) and TLR (Thrombocyte to Lymphocyte Ratio) values in patients with HL compared to those without (2,38±0,70; 1,97±0,59 p=0,016 and 133,79±39,06; 109,03±29,00 p=0,005). Another important finding was that the albumin values of patients with HL were found to be statistically significantly lower (4.42 ± 0.41; 4.67 ± 0.29 p = 0.008).
 Conclusion: 29.3% of patients had HL. We found significant increase in NLR and TLR in pneumoconiosis patients with HL and decrease in serum albumin levels. We think that these markers may have prognostic value in pneumoconiosis patients with lymphadenopathy.

Assessment of impact of combined heat on the environment of urbanized areas (case study of Ulan-Ude, Russia)

Combined heat and power plants (CHPP) are an important component of the energy balance in many countries. However, of all types of power plants, CHPPs have the largest impact on the environment. In recent years, the urban ecology has become one of the key indicators that determine the quality of life of city residents. The article evaluates the impact of the CHPPs in Ulan-Ude on the example of CHPP-1. The main sources of environmental pollution, and, accordingly, the zone of exposure of CHPP-1’ pollutants have been identified. Virtually the entire territory of the city of Ulan-Ude falls under this zone, but since northwestern winds prevail in this area, the north-western part of the city is most affected. Based on the results of a detailed dispersion calculation, we defined the following substances which should be monitored: nitrogen dioxide, sulfur dioxide, mineral oil, and inorganic dust (70-20% SiO2 and coal dust). The concentration of these substances in the air is significant.

Ecological impact on the environment of industrial mining of bentonite clays

The object of the study is the Kattakurgan deposit of bentonite clays. During the implementation of the project, an environmental analysis of the design solution and the facility itself was carried out in terms of emissions, discharges, waste generation, and the degree of their impact on the environment was assessed. As a result of the environmental analysis, 6 sources of emission of pollutants, 4 unorganized sources of emissions of harmful substances of the area type were identified. The main source of air pollution is the bentonite clay quarry. In terms of ingredients, inorganic dusts account for the bulk of emissions. Analysis of the dispersion fields of pollutant emissions showed that the maximum ground-level concentrations of the considered harmful substances outside the enterprise do not exceed the values established by quotas. The water supply of the enterprise is carried out at the expense of imported water. Wastewater only includes domestic wastewater. An inventory of production and consumption wastes was carried out. It has been established that 5 types of waste are generated in the process of production activities of the deposit. The waste is non-toxic and low-hazard. Calculation of limits for disposal of production waste.

Modelling of the Chemical Halo of Dust Pollution Migration in Loparite Ore Tailings Storage Facilities

The article presents a study of the environmental impact of dusting tailing dumps of rare-metal ore dressing in the Murmansk region of Russia. The purpose of the study was to establish patterns in the atmochemical halo migration of the dust pollution of loparite ore dressing tailings. The geotechnical characteristics and material composition of the tailings material have been investigated. Potentially dusty areas identified. Models of dispersion of inorganic dust under different meteorological scenarios are constructed: at low wind load, normal and unfavorable meteorological conditions. The modeling of the spread of pollutants in the area exposed to dust at the storage site was carried out in the program for modeling atmospheric pollution Ecolog-4.60. Calculation of the dispersion of inorganic dust containing 20–70% SiO2 showed that the atmochemical halo of tailings dust pollution spreads over tens of kilometers, and already at a wind speed of about 8 m/s, the concentration of suspended solids at the border of the enterprise sanitary protection zone exceeds the maximum one-time maximum permissible concentration is 3–3.3 times, and under unfavorable meteorological conditions—Dusting reaches the boundaries of the residential area (inhabited locality Revda), located in the north-west of the enterprise, and exceeds the MPCm.o. 1.5 times.

Influencing Factors of Peripheral Blood Lymphocyte subsets in Workers with Chronic Obstructive Pulmonary Disease Exposed to Inorganic Dust, 만성폐쇄성폐질환을 동반한 무기분진 노출 이직근로자의 혈중 림프구 아형분포에 미치는 영향요인

Influencing Factors of Peripheral Blood Lymphocyte subsets in Workers with Chronic Obstructive Pulmonary Disease Exposed to Inorganic Dust, 만성폐쇄성폐질환을 동반한 무기분진 노출 이직근로자의 혈중 림프구 아형분포에 미치는 영향요인

Pathogenetic bases of the use of antifibrotic therapy with Bovhyaluronidazum azoximerum in patients with new coronavirus infection COVID-19

One of the most likely and serious complications of the novel coronavirus infection (COVID-19) is pneumofibrosis, which can negatively affect the duration and quality of life of patients who have suffered from this disease. The appearance of fibrotic changes in COVID-19 is due to a number of pathological processes that occur in the lungs after the pathogen, the SARS- CoV-2 virus, enters there. First of all, an inflammatory response is triggered, which is mediated by macrophages and granulocytes, due to which the synthesis of pro-inflammatory cytokines, incl. IL-1, TNF, which are potent inducers of hyaluronic acid synthetase. There is a decrease in the content of fibrinolysis activators in the pulmonary endothelium, which contributes to the accumulation of fibrin in the vessels of the lungs. Fibrin can escape into the interstitial space and cause the formation of sclerosing alveolitis. The increasing defeat of pneumocytes favors the release of fibrin into the lumen of the alveoli, which causes the formation of hyaline membranes. The regulation of the fibrotic process involves immunocompetent cells, primarily CD4 + T-lymphocytes, which are capable of producing cytokines, chemokines and growth factors, and these, in turn, stimulate the proliferation and differentiation of fibroblasts, as well as their production of collagen. The more severe forms of infectious process can lead to the greater risk of developing fibrotic changes. Risk factors are a large area of lung damage, the use of artificial pulmonary ventilation, ARDS, fibrosis in anamnesis. An additional role in the pathomorphogenesis of pneumofibrosis is played by smoking, external inhalation effects (inhalation of organic and inorganic dust), gastroesophageal reflux, type II diabetes mellitus, genetic factors (familial idiopathic pulmonary fibrosis). The pathogenetic features of COVID-19 require administration of anti-fibrotic treatment. Bovhyaluronidazum azoximerum, a drug that is a conjugate of the proteolytic enzyme hyaluronidase, is considered as an antifibrotic agent. The treatment regimens with this drug recommended in the period of convalescence for patients who have undergone COVID-19 are given.

Blood, sweat, and tears: extraterrestrial regolith biocomposites with in vivo binders.

The proverbial phrase ‘you can’t get blood from a stone’ is used to describe a task that is practically impossible regardless of how much force or effort is exerted. This phrase is well-suited to humanity’s first crewed mission to Mars, which will likely be the most difficult and technologically challenging human endeavor ever undertaken. The high cost and significant time delay associated with delivering payloads to the Martian surface means that exploitation of resources in situ — including inorganic rock and dust (regolith), water deposits, and atmospheric gases — will be an important part of any crewed mission to the Red Planet. Yet there is one significant, but chronically overlooked, source of natural resources that will — by definition — also be available on any crewed mission to Mars: the crew themselves. In this work, we explore the use of human serum albumin (HSA) — a common protein obtained from blood plasma — as a binder for simulated Lunar and Martian regolith to produce so-called ‘extraterrestrial regolith biocomposites (ERBs).’ In essence, HSA produced by astronauts in vivo could be extracted on a semi-continuous basis and combined with Lunar or Martian regolith to ‘get stone from blood’, to rephrase the proverb. Employing a simple fabrication strategy, HSA-based ERBs were produced and displayed compressive strengths as high as 25.0 MPa. For comparison, standard concrete typically has a compressive strength ranging between 20 and 32 MPa. The incorporation of urea — which could be extracted from the urine, sweat, or tears of astronauts — could further increase the compressive strength by over 300% in some instances, with the best-performing formulation having an average compressive strength of 39.7 MPa. Furthermore, we demonstrate that HSA-ERBs have the potential to be 3D-printed, opening up an interesting potential avenue for extraterrestrial construction using human-derived feedstocks. The mechanism of adhesion was investigated and attributed to the dehydration-induced reorganization of the protein secondary structure into a densely hydrogen-bonded, supramolecular β-sheet network — analogous to the cohesion mechanism of spider silk. For comparison, synthetic spider silk and bovine serum albumin (BSA) were also investigated as regolith binders — which could also feasibly be produced on a Martian colony with future advancements in biomanufacturing technology.

Surveillance of work-related asthma including the emergence of a cannabis-associated case series in Washington State

Objective We conducted surveillance for work-related asthma (WRA) in Washington State to identify the industry sectors and asthma exposures most commonly affecting injured workers and in need of prevention activities. Methods Using workers’ compensation data as the primary data source, valid cases were classified as work-aggravated asthma (WAA) or new onset asthma that includes occupational asthma (OA) and reactive airways dysfunction syndrome (RADS). The source of exposure that caused the worker’s asthma, their industry and occupation were determined. Results There were 784 valid work-related asthma cases identified for the period 2009–2016, WAA (n = 529) was most common followed by occupational asthma (n = 127) and RADS (n = 12). The Health Care and Social Assistance industry had the highest number of cases (n = 170) with 82% classified as WAA. The highest overall proportions of new onset asthma are occurring in Agriculture, Forestry, Fishing and Hunting (33% of work related asthma cases), Manufacturing (31%) and Construction (30%). The leading substances associated with new onset asthma across all industries include hop plant dust, wood and cedar dust, mineral and inorganic dust, mold, and cleaning materials. We describe ten cases of cannabis-associated asthma including seven from workers in the legalized cannabis industry, four of whom had OA. Conclusion State-based work-related asthma surveillance is critical in identifying the workers and exposures associated with this occupational disease, including the detection of a case-series in the cannabis industry.

Associations between occupational and environmental exposures and organ involvement in sarcoidosis: a retrospective case-case analysis

BackgroundSarcoidosis most commonly affects lungs and intrathoracic lymph nodes, but any other organ can be involved. In epidemiological studies, many occupational and environmental exposures have been linked to sarcoidosis but their relationship with the disease phenotype has barely been studied.ObjectiveTo investigate how occupational and environmental exposures prior to diagnosis relate to organ involvement in patients with sarcoidosisMethodsWe retrospectively studied patients seen at a sarcoidosis clinic between 2017 and 2020. Patients were included if they had a clinical presentation consistent with sarcoidosis and histologically confirmed epithelioid granulomas or had Löfgren syndrome. In a case–case analysis using multivariable logistic regression we calculated odds ratios (OR) of prespecified exposure categories (based on expert ascertainment) for cases with a given organ involvement versus cases without this organ involvement.ResultsWe included 238 sarcoidosis patients. Sarcoidosis limited to pulmonary involvement was associated with exposure to inorganic dust prior to diagnosis (OR 2.11; 95% confidence interval [CI] 1.11–4.17). Patients with liver involvement had higher odds of contact with livestock (OR 3.68; 95% CI 0.91–12.7) or having jobs with close human contact (OR 4.33; 95% CI 1.57–11.3) than patients without liver involvement. Similar associations were found for splenic involvement (livestock: OR 4.94, 95% CI 1.46–16.1; close human contact: OR 3.78; 95% CI 1.47–9.46). Cardiac sarcoidosis was associated with exposure to reactive chemicals (OR 5.08; 95% CI 1.28–19.2) or livestock (OR 9.86; 95% CI 1.95–49.0). Active smokers had more ocular sarcoidosis (OR 3.26; 95% CI 1.33–7.79).ConclusionsOur study indicates that, in sarcoidosis patients, different exposures might be related to different organ involvements—hereby providing support for the hypothesis that sarcoidosis has more than one cause, each of which may promote a different disease phenotype.

Effects of Occupational Inorganic Dust Exposure on Plasma Glutathione.

The article’s abstract is not available.

Clinical and tomographic characterization of patients with interstitial lung disease at the Trujillo Regional Teaching Hospital, Peru.

To determine the main clinical and tomographic characteristics of patients with diffuse interstitial lung disease at Trujillo Regional Teaching Hospital. Case series. Tomographic examinations and clinical data were obtained from patients with interstitial pulmonary disease who attended the pulmonology service of Trujillo Regional Teaching Hospital. The information collected was recorded and systematized in Excel. For the statistical analysis, SPSS 23.0 program was used. Data from 103 patients were obtained, of which 60.2% were female, and 39.8% were male. The average age was 72 years for both groups. Main clinical manifestations were cough (82.5%), dyspnea (76.7%), joint pain (43.7%), weight loss (40.8%), velcro crackles (35%) and digital clubbing (28.2%). Exposure to wood smoke was present in 46.6%, exposure to inorganic dust in 12.6% and fowl ownership in 9.7% of cases. Thirty-one (30.1%) patients presented comorbidities. Among these, rheumatic diseases and arterial hypertension were the most frequent. Non-specific interstitial pneumonia pattern was present in 26.2% of the cases; probable usual interstitial pneumonia in 16.5%; organized type in 12.6%; usual interstitial in 10.7%; acute interstitial in 2.9% and 27.1% had no defined tomographic pattern. In the studied population, clinical and tomographic characteristics of interstitial lung parenchymal diseases are variable in magnitude and forms of presentation. Female sex and exposure to fuels were the most frequent associated factors. Connective tissue diseases could also explain study findings.

Inorganic Dust Exposure During Military Service as a Predictor of Rheumatoid Arthritis and Other Autoimmune Conditions.

ObjectiveRheumatoid arthritis (RA) and other autoimmune (AI) conditions are associated with inorganic dust exposure. Many military activities are likely to entail inorganic dust exposures. We wished to identify associations between prior military dust exposure and RA and other AI conditions.MethodsWe studied persons from a roster of Army, Navy, Air Force, or Marine Corps personnel who had served in Operation Enduring Freedom and Operations Iraqi Freedom and New Dawn. We linked military occupational codes to a job exposure matrix assigning dust exposure likelihood. We used the Veterans Affairs Health Care System (VAHCS) electronic health care records to identify cases of RA, systemic lupus erythematosus (SLE), systemic sclerosis (SSc), vasculitis, and inflammatory myositis. Generalized estimating equations modeled risk of RA and other AI conditions associated with dust exposure, taking into account military service branch, age at first VAHCS encounter, sex, race/ethnicity, smoking status, and years of military service.ResultsOf 438 086 veterans (68% ever‐smokers), 44% were classified with likely or somewhat likely dust exposure. Cases included 1139 cases with RA, 467 cases with SLE, and 180 cases with other AI diseases (SSc, vasculitis, or inflammatory myositis). Military dust exposure was associated with increased odds of RA (odds ratio [OR] = 1.10; 95% confidence interval [CI] = 1.003‐1.20) and increased odds of SSc, vasculitis, or inflammatory myositis (OR = 1.23; 95% CI = 1.14‐1.34) but was protective for SLE (OR = 0.81; 95% CI = 0.76‐0.88).ConclusionDust exposure during past military service comprises an occupational and environmental risk factor for RA and other AI diseases. This is potentially relevant for prevention activities.

Sarcoidosis: Review of Diagnosis and Treatment

Background: Sarcoidosis is a systemic heterogenous granulomatous disease of unknown etiology that results in inflammation of pulmonary and extrapulmonary sites. In a minority of patients it can result in fibrosis and permanent organ damage. Most commonly mentioned causes of sarcoidosis include atypical mycobacterium, proprionobacterium and inorganic dusts. Once exposed to an organic or inorganic, an Antigen Presenting Cell (APC) prepares and presents the antigen to a T cell and its respective HLA locus. In a susceptible person, this provides cytokine production, differentiation into T helper cells and provokes an immune response that in its early stages is allayed by corticosteroids or other immunomodulatory agents. In the majority of patients appropriate immunomodulatory therapy will control the disease and prevent progression. However, in 20-25 % the disease can progress and lead to organ damage or compromise and fibrosis. Sarcoidosis is a relatively common disease with an incidence of 2.3-17.8 per 100,000. It is 2-4 times more common in African Americans than Caucasian Americans with the mean age of onset of 45-50 years of age. Unlike autoimmune rheumatic disease the disease occurs almost as commonly in men than women. Sources: A Medline, Pub Med review from 1999-2021. Spectrum of Disease: Sarcoidosis occurs in 90-98 % of patients during the course of their disease. Eleven to twenty two percent of patients have involvement of either the liver, Skin, ocular (uveitis), Lymph nodes and spleen. The upper airway, liver, CNS and heart comprise <10% of cases each and the bone, joints/ muscle, and hypercalcemia < 5%. Diagnosis: With the exception of Lofgren’s and Heerfordt’syndromes the presence of non-caseating/necrotizing granuloma must be present on biopsy of at least one site and mycobacterial or fungal infections or malignancy must be ruled out. If clinically suspicious, Skin and peripheral lymph nodes are the least invasive areas for biopsy and if hilar or mediastinal nodes are suggestive, an EBUS approach is recommended. In organs such as the heart and CNS where biopsy is either insensitive or invasive, a Cardiologist and Neurologist in concert with a Rheumatologist can make a probable diagnosis based on clinical presentation, PET or MRI and exclusion of alternative diseases.

The impact of air pollution during the liquidation and recultivation of mine workings on health problems risk of the population in an industrial city

Introduction. The Kemerovo region is the largest coal-producing region in Russia, and coal mining hurts the environment. The earth's developed mineral deposits are sources of pollution of atmospheric air, water, and soil. They increase the risk to public health. The implementation of measures for the reclamation of disturbed land is an urgent problem. The study aims to assess the health of an industrial city from air pollution during the liquidation of mining operations, and reclamation works carried out at a coal mine. Materials and methods. The scientists assessed the distribution and impact of atmospheric emissions at 40 plotted points based on a map of the city of Kisilevsk in the Kemerovo region. We calculated the maximum and average annual concentrations of pollutants and identified the risk of chronic intoxication and carcinogenic risk. Scientists obtained risk values with acceptable levels. The risk values were determined, taking into account the background concentrations of substances. Results. The researchers revealed priority pollutants: inorganic dust, nitrogen dioxide, nitrogen oxide, sulfur dioxide, carbon (soot), carbon monoxide. There is no excess of the maximum average annual concentrations during the liquidation and reclamation at the coal mine for all pollutants. The combined values of the risk of chronic intoxication and carcinogenic risk do not exceed the acceptable level. The total values of the risk of chronic intoxication, taking into account the background concentrations of pollutants, exceed the proper level at all points of exposure. Conclusions. Activities for the elimination and reclamation of mine workings do not significantly impact the environment and the health of the population of the city of Kiselevsk.

Морфологические особенности и элементный состав пылевого загрязнения фотоэлектрического модуля

In this work, scanning electron microscopy and X-ray energy dispersive analysis methods were used to study the morphology and composition of dust and dirt that accumulates on the protective glass surface of the photovoltaic module. These modules are located in the local Tashkent area. It is shown here that the sizes of the inorganic particles varied from 2 μm to 75 μm, while the organic particles are up to several millimeters in size. The inorganic dust component consists of particles with different shapes, while the organic dust is characterized by a fibrous structure in which holes and micropores were found. Elemental composition studies have shown significant differences between samples of inorganic and organic origin. Analysis of the elemental composition showed a high weight fraction of oxygen, indicating its chemical bonding in compounds with silicon, calcium, carbon and iron, which suggests the presence of these elements in the form of stable oxides. It is shown that organic pollution components contains oxygen, carbon, nitrogen and phosphorus, which may indicate a high content of organic compounds in the form of plant fibers and oxides; the last two elements are characteristic of bird waste products. These studies that were carried out to determine the morphological features and to quantitatively analyze the composition of the dust and dirt that accumulates on the protective glass surface of the photovoltaic module allows us to conclude that the search for methods for preventing and cleaning this accumulation on the front surface of the modules should be targeted for particles of inorganic origin with longitudinal dimensions of up to 30 μm and at the same time it is necessary to look for ways to deterio- rate their adhesive properties. Another important conclusion in the case of organic pollution is that the organic compounds found in bird droppings are in a water-soluble form, which allows you to clean the surface of photovoltaic modules without the use of special detergents.

Chemical Composition and Source Analysis of PM2.5 in Yuncheng, Shanxi Province in Autumn and Winter

In order to reveal the chemical composition characteristics and pollution sources of fine particulate matter (PM2.5) in autumn and winter in Yuncheng, PM2.5 samples were continuously collected using a four-channel small-flow particulate sampler from October 15, 2018 to March 15, 2019. The study prediminantly analyzed the chemical components of water-soluble ions, elemental carbon, organic carbon, and metal elements. Additionally, the chemical mass reconstruction method of particulate matter and the positive matrix factorization model (PMF) were combined for an in-depth discussion. During the sample period, the PM2.5 mass concentrations range was 29.37-370.11 μg·m-3, and 101 days during the sampling period exhibited concentrations that were higher than the secondary standard in China's Ambient Air Quality Standards (GB 3095-2012), with an exceeding rate of 70.63%. These results indicate that the air pollution in Yuncheng in autumn and winter is serious. According to the air quality index (AQI), the collected samples are classified as clean, light-moderate pollution, and heavy-severe pollution. Water-soluble ions, OC, EC and metal elements account for 40%, 19%, 5%, and 7% on clean days, 46%, 18%, 4%, and 5% on days with light-moderate pollution, and 46%, 21%, 4%, and 4% on days with heavy-severe pollution, respectively. Secondary ions NO3-, SO42-, and NH4+ are the primary components of water-soluble ions, accounting for 81% (clean days), 87% (light-moderate pollution), and 87% (heavy-severe pollution) of the total ion concentration, respectively. The OC/EC ratios during the sampling period were 3.78 (clean days), 4.02 (light-moderate pollution), and 5.37 (heavy-severe pollution). With the intensification of pollution, the pollution of secondary organic aerosols in the atmosphere becomes increasingly serious. In addition, as the air pollution increased, the concentration of Fe and Cr elements gradually decreased, while the concentration of other metal elements showed an overall upward trend. The results of the chemical mass reconstruction demonstrate that among the different pollution levels of atmospheric PM2.5 in Yuncheng, the mass percentages of secondary inorganic salt, sea salt, heavy metals, mineral dust, construction dust, organic matter, and elemental carbon were 36%, 2%, 2%, 8%, 1%, 33%, and 5% (clean days), 41%, 1%, 1%, 5%, 0.01%, 31%, and 5% (light-moderate pollution), and 41%, 1%, 1%, 4%, 0.004%, 34%, and 4% (heavy-severe pollution). The proportion of secondary inorganic ions increased and mineral dust decreased with the deterioration of air quality. The PMF analysis results suggest that secondary related sources, coal combustion sources, vehicle exhaust sources, biomass burning, and secondary organic matter are the predominant sources of PM2.5 during serious air pollution in Yuncheng.

Occupational exposure to carcinogens in Brazil: An approach

This study aims to estimate the prevalence of the primary occupational exposures, considered risk factors for Cancer in Brazil. We elaborated two exposure scenarios considering the agents' classification and the intensity of exposure, stratified by Brazilian regions and sex. Two pairs of specialists performed the classification of economic activities and occupations due to exposure. There was an excellent overall agreement (94%) and acceptable overall reliability (kappa 0.92, 95% CI 0.89–0.95). There is a notable difference (595%) in occupational exposure between the north (with a higher concentration of rural areas and extractivism) and southeast (with a higher level of industrial activities). There is a difference in prevalence from 833% for solvents to 1170% for inorganic dust between the two scenarios. There is a heterogeneity of exposures according to location, sex, circumstance, and sensitiveness of classification.

Characteristics of chemical profile, sources and PAH toxicity of PM2.5 in beijing in autumn-winter transit season with regard to domestic heating, pollution control measures and meteorology

Several air pollution episodes occurred in Beijing before and after the 2014 Asia-Pacific Economic Cooperation (APEC) summit, during which air-pollution control measures were implemented. Within this autumn-winter transit season, domestic heating started. Such interesting period merits comprehensive chemical characterization, particularly the organic species, to look into the influence of additional heating sources and the control measures on air pollution. Therefore, this study performed daily and 6h time resolved PM2.5 sampling from the 24th October to 7th December, 2014, followed by comprehensive chemical analyses including water-soluble ions, elements and organic source-markers. Apparent alterations of chemical profiles were observed with the initiation of domestic heating. Through positive matrix factorization (PMF) source apportionment modeling, six PM2.5 sources including secondary inorganic aerosol (SIA), traffic emission, coal combustion, industry emission, biomass burning and dust were separated and identified. Coal combustion was successfully distinguished from traffic emission by hopane diagnostic ratio. The result of this study reveals a gradual shift of dominating sources for PM pollution episodes from SIA to primary sources after starting heating. BaPeq toxicity from coal combustion increased on average by several to dozens of times in the heating period, causing both long-term and short-term health risk. Air mass trajectory analysis highlights the regional influence of the industry emissions from the area south to Beijing. Control measures taken during APEC were found to be effective for reducing industry source, but less effective in reducing the overall PM2.5 level. These results provide implications for policy making regarding appropriate air pollution control measures.

Wood burning pollution in Chile: A tale of two mid-size cities

Cities in southern Chile are facing high levels of PM2.5 because of wood burning pollution. We quantify the contribution of wood smoke to fine particles in two mid-size cities: Molina and Valdivia, located in different climate zones. The sampling campaigns were carried out during austral winter (July to September) in 2018 (Molina) and 2019 (Valdivia). 24-h filter samples were analyzed for carbonaceous compounds, secondary ions, metals, and particle-phase organic molecular markers. Average winter concentrations of PM2.5 were 53 ± 32 μg/m3 (average ± standard deviation) in Molina and 89 ± 55 μg/m3 in Valdivia. The major component of fine particles was organic matter, representing more than 70% of PM2.5. Concentrations of organic molecular markers were used in a receptor model (US EPA CMB8.2) to identify and quantify primary sources of PM2.5. The major source of PM2.5 was wood smoke, which accounted for 41.55 ± 9.77 μg/m3 (62.9 ± 15.3%) in Molina and 43.65 ± 24.06 μg/m3 (51.7 ± 21.1%) in Valdivia. Secondary organic aerosols (SOA) generated from inefficient wood burning, contributed 20.4 ± 17.7% in Molina and 28.9 ± 27.6% in Valdivia. Secondary inorganic ions and dust are minor sources of PM2.5. The total contribution of wood smoke (adding primary wood smoke and SOA) could be as much as 83% in Molina and 81% in Valdivia, during the winter season.

In vivo Activity of Dust Inhalation at Ratcon Quarry, Sokuro Village, Oluyole, Ibadan Oyo State

A total of twenty (20) experimental adult male rats, aged 60 days (7 to 8 weeks) with average body weight between 150-200 gm were grouped, restrained inside laboratory approved plastic holders and exposed to dust inhalation at the quarry site with exposure time of 7, 14 and 21 days to reflect short-term effects while 42days represent long-term effects of dust inhalation on human beings. Each specimen was collected and sacrificed at their grouped survival periods and subjected to laboratory analysis that include Hematology and Histopathology of the lungs. The Hematologyresults of the 7 and 14days specimens revealed no remarkable changes in the Erythrogram (PCV, HB and RBC), the Leucogram (WBC) and the Platelets but however, the results of the 21 and 42 days specimen revealed leukocytosis (increase in WBC), lymphocytosis (increase Lym) and neutrophilia (increase neutrophils) (p<0.05). The Histopathology results of the first specimen (7 days exposure) showed no observable lesion, the second specimen(14 days) showed capillary congestion and mild interstitial pneumonia, while the third (21 days) and fourth (42 days) samples showed the rats graduating from mild to moderate interstitial pneumonia and oedema. The risk of these diseases depends on the amount of organic or inorganic dusts inhaled and deposited in the alveolar region, the air concentration of respirable dust as well as the exposure time and breathing pattern.