Aerosol particles (0.3–10 μm) inside an educational workshop : Emission rate and inhaled deposited dose

In this study, we measured the concentrations of accumulation and coarse particles inside an educational workshop (March 31–April 6, 2015), calculated particle emission and losses rates, and estimated inhaled deposited dose. We used an Optical Particle Sizer (TSI OPS 3330) that measures the particle number size distribution (diameter 0.3–10 μm) and we converted that into particle mass size distribution (assuming spherical particles and unit density). We focused on two particle size fractions: 0.3–1 μm (referred as PN0.3−1 and PM0.3−1) and 1–10 μm (referred as PN1−10 and PM1−10). The occupants' activities included coffee brewing, lecturing, tobacco smoking, welding, scrubbing, and sorting/drilling iron. The highest concentrations were observed during welding with PN0.3−1 (PM0.3−1) was ∼1866 cm−3 (55 μg/m3) and PN1−10 (PM1−10) was ∼7 cm−3 (103 μg/m3). The lowest concentrations were observed during coffee brewing and metal turning with PN0.3−1 (PM0.3−1) was ∼22 cm−3 (0.7 μg/m3) and PN1−10 (PM1−10) was ∼0.5 cm−3 (4 μg/m3). The emissions rate of coarse particles was 85–1010 particles/hour × cm3 whereas that for submicron particle in the diameter range 0.3–1 μm was 5.7 × 104–9.3 × 104 particles/hour × cm3 depending on the activity and the ventilation rate. The coarse particles losses rate was 0.35–2.1 h−1 and the ventilation rate was 0.24–2.1 h−1. The alveolar received the majority and particles below 1 μm with a fraction of about 53% of the total inhaled deposited dose whereas the head/throat region received about 18%. This study is important for better understanding the health effects at educational workshops.Peer reviewe

Elemental Contamination in Indoor Floor Dust and Its Correlation with PAHs, Fungi, and Gram plus /-Bacteria

In this study, we performed elemental analysis for floor dust samples collected in Jordanian microenvironments (dwellings and educational building). We performed intercorrelation and cluster analysis between the elemental, polyaromatic hydrocarbon (PAH), and microorganism concentrations. In general, the educational building workshops had the highest elemental contamination. The age of the dwelling and its occupancy played a role on the elemental contamination level: older and more occupied dwellings had greater contamination. The elemental contamination at a dwelling entrance was observed to be higher than in the living room. We found exceptionally high concentrations for Fe and Mn in the educational workshop and additionally, Hg, Cr, and Pb concentrations exceeded the limits set by the Canadian Council of Ministers of the Environment. According to the cluster analysis, we found three major groups based on location and contamination. According to the enrichment factor (EF) assessment, Al, Co, Mn, Ti, and Ba had EF 40 (i.e., extremely enriched). In contrast, Ca and P were geogenically enriched. Furthermore, significant Spearman correlations indicated nine subgroups of elemental contamination combined with PAHs and microbes.Peer reviewe

Elemental Contamination in Indoor Floor Dust and Its Correlation with PAHs, Fungi, and Gram+/− Bacteria

In this study, we performed elemental analysis for floor dust samples collected in Jordanian microenvironments (dwellings and educational building). We performed intercorrelation and cluster analysis between the elemental, polyaromatic hydrocarbon (PAH), and microorganism concentrations. In general, the educational building workshops had the highest elemental contamination. The age of the dwelling and its occupancy played a role on the elemental contamination level: older and more occupied dwellingshad greater contamination. The elemental contamination at a dwelling entrance was observed to be higher than in the living room. We found exceptionally high concentrations for Fe and Mn in the educational workshop and additionally, Hg, Cr, and Pb concentrations exceeded the limits set by the Canadian Council of Ministers of the Environment. According to the cluster analysis, we found three major groups based on location and contamination. According to the enrichment factor (EF) assessment, Al, Co, Mn, Ti, and Ba had EF 40 (i.e., extremely enriched). In contrast, Ca and P were geogenically enriched. Furthermore, significant Spearman correlations indicated nine subgroups of elemental contamination combined with PAHs and microbes

Elemental Contamination in Indoor Floor Dust and Its Correlation with PAHs, Fungi, and Gram+/− Bacteria

In this study, we performed elemental analysis for floor dust samples collected in Jordanian microenvironments (dwellings and educational building). We performed intercorrelation and cluster analysis between the elemental, polyaromatic hydrocarbon (PAH), and microorganism concentrations. In general, the educational building workshops had the highest elemental contamination. The age of the dwelling and its occupancy played a role on the elemental contamination level: older and more occupied dwellingshad greater contamination. The elemental contamination at a dwelling entrance was observed to be higher than in the living room. We found exceptionally high concentrations for Fe and Mn in the educational workshop and additionally, Hg, Cr, and Pb concentrations exceeded the limits set by the Canadian Council of Ministers of the Environment. According to the cluster analysis, we found three major groups based on location and contamination. According to the enrichment factor (EF) assessment, Al, Co, Mn, Ti, and Ba had EF 40 (i.e., extremely enriched). In contrast, Ca and P were geogenically enriched. Furthermore, significant Spearman correlations indicated nine subgroups of elemental contamination combined with PAHs and microbes

Floor dust bacteria and fungi and their coexistence with PAHs in Jordanian indoor environments

Floor dust samples were collected from Jordanian indoor environments (eight dwellings and an educational building) in Amman. Quantitative PCR (qPCR) analyses of selected fungal and bacterial groups were performed. The bacterial and fungal concentrations were also correlated with PAHs concentrations, which were previously measured in the same samples by using GC-MS. The bacterial and fungal concentrations varied significantly among and within the tested indoor environments. Based on the collected samples in the entrance area of the dwellings, the largest variation was found in Gram-negative bacteria and total fungi concentration. The lowest bacterial and fungal concentrations were found in the dwelling that was least occupied and the most recently built. At the educational building, the Gram-positive bacteria concentrations were lower than those observed in the dwellings. Unlike for bacteria, we observed significant negative correlation with some polycyclic aromatic hydrocarbons (PAHs). This calls for further studies investigating biodegradation of PAHs in house dust and presence of potentially health hazardous PAH metabolites. Since biocontamination in floor dust has been given relatively little to no attention in the MENA region we recommend that more extensive measurements be conducted in the future with chemical and biological analysis of floor dust contaminants and their exposure indoors. (C) 2017 Elsevier B.V. All rights reserved.Peer reviewe

PAHs in Household Floor Dust Collected in Amman, Jordan

Peer reviewe

Advances in air quality research – current and emerging challenges

© Author(s) 2022. This work is distributed under the Creative Commons Attribution 4.0 License. https://creativecommons.org/licenses/by/4.0/This review provides a community’s perspective on air quality research focusing mainly on developmentsover the past decade. The article provides perspectives on current and future challenges as well asresearch needs for selected key topics. While this paper is not an exhaustive review of all research areas in thefield of air quality, we have selected key topics that we feel are important from air quality research and policy perspectives. After providing a short historical overview, this review focuses on improvements in characterizingsources and emissions of air pollution, new air quality observations and instrumentation, advances in air qualityprediction and forecasting, understanding interactions of air quality with meteorology and climate, exposure andhealth assessment, and air quality management and policy. In conducting the review, specific objectives were(i) to address current developments that push the boundaries of air quality research forward, (ii) to highlightthe emerging prominent gaps of knowledge in air quality research, and (iii) to make recommendations to guidethe direction for future research within the wider community. This review also identifies areas of particular importancefor air quality policy. The original concept of this review was borne at the International Conferenceon Air Quality 2020 (held online due to the COVID 19 restrictions during 18–26 May 2020), but the articleincorporates a wider landscape of research literature within the field of air quality science. On air pollutionemissions the review highlights, in particular, the need to reduce uncertainties in emissions from diffuse sources,particulate matter chemical components, shipping emissions, and the importance of considering both indoor andoutdoor sources. There is a growing need to have integrated air pollution and related observations from bothground-based and remote sensing instruments, including in particular those on satellites. The research shouldalso capitalize on the growing area of low-cost sensors, while ensuring a quality of the measurements which areregulated by guidelines. Connecting various physical scales in air quality modelling is still a continual issue,with cities being affected by air pollution gradients at local scales and by long-range transport. At the same time,one should allow for the impacts from climate change on a longer timescale. Earth system modelling offers considerablepotential by providing a consistent framework for treating scales and processes, especially where thereare significant feedbacks, such as those related to aerosols, chemistry, and meteorology. Assessment of exposureto air pollution should consider the impacts of both indoor and outdoor emissions, as well as application of moresophisticated, dynamic modelling approaches to predict concentrations of air pollutants in both environments.With particulate matter being one of the most important pollutants for health, research is indicating the urgentneed to understand, in particular, the role of particle number and chemical components in terms of health impact,which in turn requires improved emission inventories and models for predicting high-resolution distributions ofthese metrics over cities. The review also examines how air pollution management needs to adapt to the abovementionednew challenges and briefly considers the implications from the COVID-19 pandemic for air quality.Finally, we provide recommendations for air quality research and support for policy.Peer reviewe

Advances in air quality research – current and emerging challenges

This review provides a community\u27s perspective on air quality research focusing mainly on developments over the past decade. The article provides perspectives on current and future challenges as well as research needs for selected key topics. While this paper is not an exhaustive review of all research areas in the field of air quality, we have selected key topics that we feel are important from air quality research and policy perspectives. After providing a short historical overview, this review focuses on improvements in characterizing sources and emissions of air pollution, new air quality observations and instrumentation, advances in air quality prediction and forecasting, understanding interactions of air quality with meteorology and climate, exposure and health assessment, and air quality management and policy. In conducting the review, specific objectives were (i) to address current developments that push the boundaries of air quality research forward, (ii) to highlight the emerging prominent gaps of knowledge in air quality research, and (iii) to make recommendations to guide the direction for future research within the wider community. This review also identifies areas of particular importance for air quality policy. The original concept of this review was borne at the International Conference on Air Quality 2020 (held online due to the COVID 19 restrictions during 18–26 May 2020), but the article incorporates a wider landscape of research literature within the field of air quality science. On air pollution emissions the review highlights, in particular, the need to reduce uncertainties in emissions from diffuse sources, particulate matter chemical components, shipping emissions, and the importance of considering both indoor and outdoor sources. There is a growing need to have integrated air pollution and related observations from both ground-based and remote sensing instruments, including in particular those on satellites. The research should also capitalize on the growing area of low-cost sensors, while ensuring a quality of the measurements which are regulated by guidelines. Connecting various physical scales in air quality modelling is still a continual issue, with cities being affected by air pollution gradients at local scales and by long-range transport. At the same time, one should allow for the impacts from climate change on a longer timescale. Earth system modelling offers considerable potential by providing a consistent framework for treating scales and processes, especially where there are significant feedbacks, such as those related to aerosols, chemistry, and meteorology. Assessment of exposure to air pollution should consider the impacts of both indoor and outdoor emissions, as well as application of more sophisticated, dynamic modelling approaches to predict concentrations of air pollutants in both environments. With particulate matter being one of the most important pollutants for health, research is indicating the urgent need to understand, in particular, the role of particle number and chemical components in terms of health impact, which in turn requires improved emission inventories and models for predicting high-resolution distributions of these metrics over cities. The review also examines how air pollution management needs to adapt to the above-mentioned new challenges and briefly considers the implications from the COVID-19 pandemic for air quality. Finally, we provide recommendations for air quality research and support for policy

Exposure to coarse particles and floor dust biological and chemical contamination inside Jordanian indoor environments

This thesis consists of two parts where Indoor Environmental Quality is studied in the first part by analyzing polycyclic aromatic hydrocarbons (PAHs) and biological contamination levels in floor dust inside an educational building and dwellings within the capital city of Jordan (Amman). Exposure, dose and health risk assessments of PAHs were also performed. The second part investigates particle distribution of accumulation and coarse particles as well as workers’/students’ exposure to coarse particles inside an educational workshop. For the first part of the thesis, floor dust samples were taken from the living room and the entrance area inside eight houses as well as from four offices, two lecture rooms, two corridors and two areas of a workshop inside a university building. For the second part, the inhaled deposited dose of coarse particles inside an educational workshop was estimated. The total PAHs concentrations at the living rooms ranged from around 64165422 ng/g and at the entrance area from 2419266 ng/g. Half of the dwellings had higher total PAHs concentrations at the living rooms than at the entrance area. Our findings indicated that both outdoor and indoor sources contributed to high PAHs concentrations. Based on the answers of the occupants of the dwellings, the main sources of indoor PAHs included indoor smoking, cooking activities, heating system and traffic, correlating with the results from other studies. However, more studies are needed to make a confirm conclusion regarding the specific source(s) of PAHs in household floor dust. The total PAHs concentrations inside the educational building varied from around 7145246 ng/g. The PAHs concentrations inside offices, where tobacco smoking took place, were higher than those observed inside lecture rooms and the workshop area. This finding indicated that exposure to tobacco smoking inside poorly ventilated and small indoor environments can be seriously harmful. Especially important was the fact that our results revealed that Jordanian occupants inside residential and occupational environments were less exposed to toxic PAHs via dust ingestion than occupants in similar indoor environments in Europe and Asia. The bacterial and fungal concentrations varied significantly among and within the studied environments indoors, indicating that that the origin of bio-contaminants differs depending on the locations within the city. In addition to occupancy, human’s activities and outdoor sources, environmental conditions, are also responsible for the increase of bacterial and fungal concentrations indoors. Inside the workshop area, the highest mean and maxima PN0.3-1 (PM0.3-1) and PN1-10 (PM1-10) concentrations were detected during welding activities. The variation in the accumulation mode and coarse mode aerosol concentrations could be attributed to the type of activity (i.e. specific source) and the particle loss rate (i.e. dry deposition and removal via ventilation). During an 8-hour exposure to particles produced during welding and other activities, the total estimated inhaled deposited dose would be less than 750 μg. The mass regional deposition was ~ 53% in the alveolar region, ~ 29% in the tracheobronchial and ~ 18% in the head/throat region. The results obtained for the inhaled deposited dose could be used in epidemiological studies and in the creation of risk assessment models during welding or related processes