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A special issue of International Journal of Environmental Research and Public Health (ISSN 1660-4601). This special issue belongs to the section "Environmental Science and Engineering".

Deadline for manuscript submissions: closed (31 July 2021) | Viewed by 29026

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Prof. Dr. Gianluigi de Gennaro

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Department of Biology, University of Bari Aldo Moro, 70126 Bari, Italy
Interests: atmospheric chemistry and modeling; aerosol science; Indoor Air Quality (IAQ); Volatile Organic Compounds (VOCs), Particulate Matter (PM); breath analysis; monitoring strategies; odors monitoring; emissions from materials; sensors network; PM chemical characterization; sustainability; environmental health
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Dr. Jolanda Palmisani

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Department of Biosciences, Biotechnologies and Environment, University “Aldo Moro”, Via Orabona 4, 70126 Bari, Italy
Interests: atmospheric pollution; indoor air quality (IAQ); volatile organic compounds (VOCs); particulate matter (PM); breath analysis; monitoring strategies; odors monitoring; emissions from materials and consumer products; primary and secondary pollutants; test emission chambers; sensors networks; PM chemical characterization
Special Issues, Collections and Topics in MDPI journals

Dr. Alessia Di Gilio

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Guest Editor

Department of Biosciences, Biotechnologies and Environment, University “Aldo Moro”, Via Orabona 4, 70126 Bari, Italy
Interests: atmospheric chemistry and modeling; indoor air quality (IAQ); volatile organic compounds (VOCs); particulate matter (PM); breath analysis; monitoring strategies; odors monitoring; emissions from materials; sensors networks; PM chemical characterization
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

In recent decades, increasing urbanization along with industrial development have remarkably contributed to particulate matter (PM) and gaseous pollutant concentration into the atmosphere. Epidemiological studies show a high correlation between inhalation exposure to atmospheric pollutants and increased incidence of respiratory diseases and cancer. In fact, it has been estimated that more than 8.0 million people worldwide are dying every year as a result of atmospheric pollution exposure. Overall exposure may be exacerbated in complex industrial and urban settlements where different anthropogenic sources coexist and synergistically affect air quality (power plants, industries, vehicle exhausts, combustion processes). Conventional methodological approaches for air quality monitoring and control are based on the measurement and characterization of the main pollutants emitted by ducted emission sources and at fixed sites, as prescribed by EU legislation. These approaches, however, do not allow accurately discriminating among different emissive contributions to identify both short-term emission sources and fugitive emissions, to monitor in real time the impact of pollutants on the surrounding area, and to intervene in case of critical events through processing control and abatement strategies. Therefore, in addition to conventional approaches, the development of innovative methodological approaches providing high temporal and spatial resolution data should be promoted in order to improve air quality monitoring and to preserve public health. Inhalation exposure to pollutants of concern may occur both outdoors and indoors. In the last few decades, indeed, the use of synthetic materials in building and furnishing, the adoption of new lifestyles, the progressive isolation of buildings, and the extensive use of products for cleaning and personal hygiene have contributed to the deterioration of indoor air quality (IAQ) and introduced new sources of risk to humans. It is therefore a priority to evaluate both indoor and outdoor air quality in order to identify critical issues and risk factors for human health.

Prof. Gianluigi de Gennaro
Dr. Jolanda Palmisani
Dr. Alessia Di Gilio
Guest Editors

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Keywords

VOCs
particulate matter
metals
odors
atmospheric pollution
indoor air quality
high resolution monitoring
remediation strategies
exposure assessment
environmental risk

Published Papers (11 papers)

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Research

23 pages, 3997 KiB

Open AccessArticle

Qualitative Exploration of the ‘Rolling Unmasking Effect’ for Downwind Odor Dispersion from a Model Animal Source

by Donald W. Wright, Jacek A. Koziel, David B. Parker, Anna Iwasinska, Thomas G. Hartman, Paula Kolvig and Landon Wahe

Int. J. Environ. Res. Public Health 2021, 18(24), 13085; https://0-doi-org.brum.beds.ac.uk/10.3390/ijerph182413085 - 11 Dec 2021

Cited by 6 | Viewed by 2796

Abstract

Solving environmental odor issues can be confounded by many analytical, technological, and socioeconomic factors. Considerable know-how and technologies can fail to properly identify odorants responsible for the downwind nuisance odor and, thereby, focus on odor mitigation strategies. We propose enabling solutions to environmental odor issues utilizing troubleshooting techniques developed for the food, beverage, and consumer products industries. Our research has shown that the odorant impact-priority ranking process can be definable and relatively simple. The initial challenge is the prioritization of environmental odor character from the perspective of the impacted citizenry downwind. In this research, we utilize a natural model from the animal world to illustrate the rolling unmasking effect (RUE) and discuss it more systematically in the context of the proposed environmental odorant prioritization process. Regardless of the size and reach of an odor source, a simplification of odor character and composition typically develops with increasing dilution downwind. An extreme odor simplification-upon-dilution was demonstrated for the prehensile-tailed porcupine (P.T. porcupine); its downwind odor frontal boundary was dominated by a pair of extremely potent character-defining odorants: (1) ‘onion’/‘body odor’ and (2) ‘onion’/‘grilled’ odorants. In contrast with the outer-boundary simplicity, the near-source assessment presented considerable compositional complexity and composite odor character difference. The ultimate significance of the proposed RUE approach is the illustration of naturally occurring phenomena that explain why some environmental odors and their sources can be challenging to identify and mitigate using an analytical-only approach (focused on compound identities and concentrations). These approaches rarely move beyond comprehensive lists of volatile compounds emitted by the source. The novelty proposed herein lies in identification of those few compounds responsible for the downwind odor impacts and requiring mitigation focus. Full article

(This article belongs to the Special Issue Outdoor and Indoor Air Quality)

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10 pages, 1574 KiB

Open AccessArticle

Screening of Particulate Matter Reduction Ability of 21 Indigenous Korean Evergreen Species for Indoor Use

by Bo-Kook Jang, Kyungtae Park, Sang Yeob Lee, Hamin Lee, Soo Ho Yeon, Boran Ji, Cheol Hee Lee and Ju-Sung Cho

Int. J. Environ. Res. Public Health 2021, 18(18), 9803; https://0-doi-org.brum.beds.ac.uk/10.3390/ijerph18189803 - 17 Sep 2021

Cited by 9 | Viewed by 2490

Abstract

The formation and pollution of particulate matter (PM), a side effect of rapid industrialization and urbanization, is considered a global issue. However, various plant species are able to effectively capture and reduce atmospheric PM concentrations. We investigated the indoor growth and morphology of 21 indigenous Korean evergreen species at low light intensities to ascertain their ability to reduce PM of aerosol particles in a closed acrylic chamber. The decrease in PM mass concentration differed significantly across species, with a significant correlation (8 h; p < 0.001). The reduction in the mass concentration of PM differed with particle size and across species. The highest reduction of PM_2.5 occurred after 8 h with Dryopteris lacera (86.8%), Ilex × wandoensis (84.9%), Machilus thunbergii (84.3%), and Rhododendron brachycarpum (84.0%). Reduction of PM₁₀ after 8 h was highest with Cephalotaxus harringtonii (98.3%), I. × wandoensis (98.5%), M. thunbergii (98.5%), and R. brachycarpum (98.3%). Plant morphological characteristics (category, plant height, leaf shape, leaf area) and relative humidity were closely related to the decrease in PM mass concentration. In conclusion, our findings can be used to identify Korean plant species that can reduce PM concentration and are suitable for indoor use. Full article

(This article belongs to the Special Issue Outdoor and Indoor Air Quality)

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20 pages, 53448 KiB

Open AccessArticle

Effect of the COVID-19 Lockdown on Air Pollution in the Ostrava Region

by Jan Bitta, Vladislav Svozilík and Aneta Svozilíková Krakovská

Int. J. Environ. Res. Public Health 2021, 18(16), 8265; https://0-doi-org.brum.beds.ac.uk/10.3390/ijerph18168265 - 04 Aug 2021

Cited by 6 | Viewed by 1953

Abstract

A proper estimation of anti-epidemic measures related to the influence of the COVID-19 outbreak on air quality has to deal with filtering out the weather influence on pollution concentrations. The goal of this study was to estimate the effect of anti-epidemic measures at three pollution monitoring stations in the Ostrava region. Meteorological data were clustered into groups with a similar weather pattern, and pollution data were divided into subsets according to weather patterns. Then each subset was evaluated separately. Our estimates showed a 4.1–5.7% decrease in NO_x concentrations attributed to lower traffic intensity during the lockdown. The decrease of PM_2.5 varied more significantly between monitoring stations. The highest decrease (4.7%) was detected at the traffic monitoring station, while there was no decrease detected at the rural monitoring station, which focuses mainly on domestic heating pollution. The key result of the study was the development of an analytical method that is able to take into account the effect of meteorological conditions. The method is much simpler and easy to replicate as an alternative to other published methods. Full article

(This article belongs to the Special Issue Outdoor and Indoor Air Quality)

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18 pages, 3308 KiB

Open AccessArticle

Assessment of Home-Based and Mobility-Based Exposure to Black Carbon in an Urban Environment: A Pilot Study

by Max Gerrit Adam, Phuong Thi Minh Tran, David Kok Wai Cheong, Sitaraman Chandra Sekhar, Kwok Wai Tham and Rajasekhar Balasubramanian

Int. J. Environ. Res. Public Health 2021, 18(9), 5028; https://0-doi-org.brum.beds.ac.uk/10.3390/ijerph18095028 - 10 May 2021

Cited by 4 | Viewed by 3012

Abstract

The combustion of fossil fuels is a significant source of particulate-bound black carbon (BC) in urban environments. The personal exposure (PE) of urban dwellers to BC and subsequent health impacts remain poorly understood due to a lack of observational data. In this study, we assessed and quantified the levels of PE to BC under two exposure scenarios (home-based and mobility-based exposure) in the city of Trivandrum in India. In the home-based scenario, the PE to BC was assessed in a naturally ventilated building over 24 h each day during the study period while in the mobility-based scenario, the PE to BC was monitored across diverse microenvironments (MEs) during the day using the same study protocol for consistency. Elevated BC concentrations were observed during the transport by motorcycle (26.23 ± 2.33 µg/m³) and car (17.49 ± 2.37 µg/m³). The BC concentrations observed in the MEs decreased in the following order: 16.58 ± 1.38 µg/m³ (temple), 13.78 ± 2.07 µg/m³ (restaurant), 11.44 ± 1.37 µg/m³ (bus stop), and 8.27 ± 1.88 µg/m³ (home); the standard deviations represent the temporal and spatial variations of BC concentrations. Overall, a relatively larger inhaled dose of BC in the range of 148.98–163.87 µg/day was observed for the mobility-based scenario compared to the home-based one (118.10–137.03 µg/day). This work highlights the importance of reducing PE to fossil fuel-related particulate emissions in cities for which BC is a good indicator. The study outcome could be used to formulate effective strategies to improve the urban air quality as well as public health. Full article

(This article belongs to the Special Issue Outdoor and Indoor Air Quality)

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18 pages, 517 KiB

Open AccessArticle

Transdisciplinary Research on Indoor Environment and Health as a Social Process

by Kristian Stålne and Eja Pedersen

Int. J. Environ. Res. Public Health 2021, 18(8), 4379; https://0-doi-org.brum.beds.ac.uk/10.3390/ijerph18084379 - 20 Apr 2021

Cited by 4 | Viewed by 2179

Abstract

Although issues concerning indoor environments and their interaction with humans span many disciplines, such as aerosol technology, environmental psychology, health, and building physics, they are often studied separately. This study describes a research project with the transdisciplinary aim of bridging such disciplinary boundaries. Semi-structured interviews were conducted with the twelve project members to explore their understanding of transdisciplinarity regarding the conceptual as well as social aspects of collective learning and leadership and the measures taken to achieve this. The interviews were coded in NVivo (QSR International, Doncaster, Australia), which was used to identify themes concerning notions associated with transdisciplinarity, collective leadership, collective intelligence, and learning. A shared understanding of transdisciplinarity meant that the researchers transcended their disciplinary boundaries by moving into each other’s fields. This collective learning process was facilitated by introductory lectures on each other’s fields, contributing to collective leadership and a safe atmosphere. We argue that a transdisciplinary approach is appropriate in order to address indoor environment issues as well other complex problems, for which additional time and resources should be allocated for individual and collective learning processes. Full article

(This article belongs to the Special Issue Outdoor and Indoor Air Quality)

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17 pages, 8438 KiB

Open AccessArticle

Effects of Vehicle Load on Emissions of Heavy-Duty Diesel Trucks: A Study Based on Real-World Data

by Xin Wang, Guohua Song, Zhiqiang Zhai, Yizheng Wu, Hang Yin and Lei Yu

Int. J. Environ. Res. Public Health 2021, 18(8), 3877; https://0-doi-org.brum.beds.ac.uk/10.3390/ijerph18083877 - 07 Apr 2021

Cited by 17 | Viewed by 3150

Abstract

Vehicle loads have significant impacts on the emissions of heavy-duty trucks, even in the same traffic conditions. Few studies exist covering the differences in emissions of diesel semi-trailer towing trucks (DSTTTs) with different loads, although these vehicles have a wide load range. In this context, the operating modes and emission rates of DSTTTs were analyzed under varying loads scenarios to understand the effect of vehicle loads on emission factors. First, second-by-second field speed data and emission data of DSTTTs with different loads were collected. Then, the methods for calculating the scaled tractive power (STP) and the emissions model for DSTTTs were proposed to evaluate the effect of different loading scenarios. The STP distributions, emission rate distributions, and emission factor characteristics of different loaded trucks were analyzed and compared. The results indicated that the STP distributions of DSTTTs that under the unloaded state were more narrow than those under fully loaded or overloaded conditions. The emission rates of carbon dioxide (CO₂), carbon monoxide (CO) and total hydrocarbon (THC) for DSTTTs under a fully loaded state were significantly higher than those under an unloaded state. However, due to the influence of exhaust temperature, the emission rates of nitrogen oxides (NO_x) among fully loaded trucks were lower than those under the unloaded state when STP bin was above 4 kW/ton. The emission factors of CO₂, CO, THC, and NO_x for fully loaded trucks demonstrated the largest increases at low-speed intervals (0–30 km/h), which rose by 96.2%, 47.9%, 27.8%, and 65.2%, respectively. Full article

(This article belongs to the Special Issue Outdoor and Indoor Air Quality)

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14 pages, 4312 KiB

Open AccessArticle

Study on Characteristics of Particulate Matter Resuspension in School Classroom through Experiments Using a Simulation Chamber: Influence of Humidity

by Sunghee Cho, Gahye Lee, Duckshin Park and Minjeong Kim

Int. J. Environ. Res. Public Health 2021, 18(6), 2856; https://0-doi-org.brum.beds.ac.uk/10.3390/ijerph18062856 - 11 Mar 2021

Cited by 8 | Viewed by 2077

Abstract

Resuspension of particulate matter (PM) in classrooms, which increases the risk of negative impact on student health from exposure to PM, is influenced by humidity level in the indoor environment. The goal of this study is to investigate the properties of PM resuspension in accordance with relative humidity through classroom test chamber experiments. In actual classrooms, it is challenging to control factors influencing resuspension. Therefore, the classroom chamber that reflects the environment of elementary school classroom (e.g., structure, floor material) is used in this study. The humidity of the classroom chamber is adjusted to 35%, 55%, 75%, and 85% by placing it inside a real-size environmental chamber, which allows artificial control of climatic conditions. At the respective humidity conditions, PM resuspension concentration and resuspension factor caused by occupant walking across the classroom chamber are analyzed. The results show that both of the resuspension concentration and resuspension factor reveal a linear negative correlation to humidity increase. Furthermore, coefficient of determination (R²) indicating goodness-of-fit of the linear regression model between the resuspension concentration and humidity is 0.88 for PM₁₀ and 0.93 for PM_2.5. It implies that accuracy of the regression model for estimating PM₁₀ and PM_2.5 resuspension concentrations is 88% and 93%, respectively. Full article

(This article belongs to the Special Issue Outdoor and Indoor Air Quality)

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16 pages, 867 KiB

Open AccessArticle

PM_2.5 and Trace Elements in Underground Shopping Districts in the Seoul Metropolitan Area, Korea

by Soo Ran Won, In-Keun Shim, Jeonghoon Kim, Hyun Ah Ji, Yumi Lee, Jongchun Lee and Young Sung Ghim

Int. J. Environ. Res. Public Health 2021, 18(1), 297; https://0-doi-org.brum.beds.ac.uk/10.3390/ijerph18010297 - 03 Jan 2021

Cited by 11 | Viewed by 2780

Abstract

We measured PM_2.5 in 41 underground shopping districts (USDs) in the Seoul metropolitan area from June to November 2017, and associated 18 trace elements to determine the sources and assess the respiratory risks. The PM_2.5 concentrations were 18.0 ± 8.0 μg/m³ inside USDs, which were lower than 25.2 ± 10.6 μg/m³ outside. We identified five sources such as indoor miscellanea, soil dust, vehicle exhaust/cooking, coal combustion, and road/subway dust, using factor analysis. Almost 67% of the total trace element concentration resulted from soil dust. Soil dust contribution increased with the number of stores because of fugitive dust emissions due to an increase in passers-by. Vehicle exhaust/cooking contribution was higher when the entrances of the USDs were closed, whereas coal combustion contribution was higher when the entrances of the USDs were open. Although miscellanea and coal combustion contributions were 3.4% and 0.7%, respectively, among five elements with cancer risk, Cr and Ni were included in miscellanea, and Pb, Cd, and As were included in coal combustion. The excess cancer risk (ECR) was the highest at 67 × 10⁻⁶ for Cr, and the ECR for Pb was lower than 10⁻⁶, a goal of the United States Environmental Protection Agency for hazardous air pollutants. Full article

(This article belongs to the Special Issue Outdoor and Indoor Air Quality)

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17 pages, 2923 KiB

Open AccessArticle

Indoor Air Quality Levels in Schools: Role of Student Activities and No Activities

by Gaetano Settimo, Luciana Indinnimeo, Marco Inglessis, Marco De Felice, Roberta Morlino, Annalisa di Coste, Alessandra Fratianni and Pasquale Avino

Int. J. Environ. Res. Public Health 2020, 17(18), 6695; https://0-doi-org.brum.beds.ac.uk/10.3390/ijerph17186695 - 14 Sep 2020

Cited by 17 | Viewed by 2840

Abstract

This work describes a methodology for the definition of indoor air quality monitoring plans in schools and above all to improve the knowledge and evaluation of the indoor concentration levels of some chemical pollutants. The aim is to guide interventions to improve the health of students and exposed staff connected with the activities carried out there. The proposed methodology is based on the simultaneous study of chemical (indoor/outdoor PM_2.5, NO₂, CO₂) and physical (temperature, humidity) parameters by means of automatic analyzers coupled with gaseous compounds (benzene, toluene, ethylbenzene, xylenes, formaldehyde and NO₂) sampled by denuders. The important novelty is that all the data were collected daily in two different situations, i.e., during school activities and no-school activities, allowing us to evaluate the exposure of each student or person. The different behaviors of all the measured pollutants during the two different situations are reported and commented on. Finally, a statistical approach will show how the investigated compounds are distributed around the two components of combustion processes and photochemical reactions. Full article

(This article belongs to the Special Issue Outdoor and Indoor Air Quality)

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12 pages, 3929 KiB

Open AccessArticle

Effect of Surface Treatment by O₃ and Chemical Activation by Alkali Metal on the Performance of ACFs on Adsorption and Desorption of BTX Gases

by Jung Hee Jang and Gi Bo Han

Int. J. Environ. Res. Public Health 2020, 17(15), 5422; https://0-doi-org.brum.beds.ac.uk/10.3390/ijerph17155422 - 28 Jul 2020

Viewed by 1710

Abstract

In order to investigate the adsorption characteristics of activated carbon fibers (ACFs) with improved surface morphologies towards volatile organic compounds (VOCs), a commercial low-grade ACF was surface modified by successive surface treatment (ST) and chemical activation (CA) process. O₃ was used as an ST agent for the formation of oxygen-containing functional groups on the carbon matrix of ACFs. CA was carried out after ST, using a KOH solution. After the successive ST-CA process, Brunauer-Emmett-Teller (BET) surface area and average pore diameter of ACFs were increased from 1483 m²/g to 2743 m²/g and enlarged from 1.931 nm to 2.512 nm, respectively. The successive ST-CA process also resulted in the adsorption capacities of benzene, toluene, and xylene of the ACFs to increase from 0.22 g_−Ben./g_−ACFs, 0.18 g_−Tol./g_−ACFs, and 0.19 g_−Xyl/g_−ACFs up to 0.37 g_−Ben./g_−ACFs, 0.35 g_−Tol./g_−ACFs, and 0.38 g_−Xyl/g_−ACFs, respectively. Full article

(This article belongs to the Special Issue Outdoor and Indoor Air Quality)

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13 pages, 2621 KiB

Open AccessArticle

Spectroscopic Assessment of Platinum Group Elements of PM₁₀ Particles Sampled in Three Different Areas in Jeddah, Saudi Arabia

by Mohammad W. Kadi, Iqbal Ismail, Nadeem Ali and Abdallah A. Shaltout

Int. J. Environ. Res. Public Health 2020, 17(9), 3339; https://0-doi-org.brum.beds.ac.uk/10.3390/ijerph17093339 - 11 May 2020

Cited by 8 | Viewed by 2641

Abstract

Platinum group elements (PGE) including Ru, Rh, Pt and Pd have been quantified in air particulate matter with an aerodynamic diameter equal or less than 10 microns (PM₁₀) using inductively coupled plasma mass spectrometry (ICP-MS). PM₁₀ aerosols have been collected from three sites representing various activities in Jeddah city, Saudi Arabia. These locations are residential site with heavy traffic, industrial site and heavy traffic and a light traffic site outside the city. To obtain reasonable data of the PGE concentrations, a group from 10 to 15 PM₁₀ samples were collected every month. The annual and seasonal variation of the mass concentration of the PGE were demonstrated. In all locations, Pt and Pd were relatively higher than Ru and Rh possibly because their main use is in automobile catalytic converters. Concentrations of observed PGE in PM₁₀ could be arranged in ascending order as: Rh < Ru < Pd < Pt. In case of Ru and Pt, there are clear similarities in terms of the overall mean concentrations at the sampling locations. Due to the high concentration of Ru, Rh and Pd at low traffic site, there are certainly other sources of these elements rather than vehicle catalytic converters. However, at the industrial/heavy traffic location, high concentrations of Ru were detected during February 2015. In addition, high Pt concentrations were also detected at the light traffic site during May 2015. Results indicate that Pt source in PM₁₀ is mainly the automobile catalytic converters. Full article

(This article belongs to the Special Issue Outdoor and Indoor Air Quality)

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