1
|
Chen R, Zhang L, Gu W, Li R, Hong H, Zhou L, Zhang J, Wang Y, Ni P, Xu S, Wang Z, Sun Q, Liu C, Yang J. Lung function benefits of traditional Chinese medicine Qiju granules against fine particulate air pollution exposure: a randomized controlled trial. Front Med (Lausanne) 2024; 11:1370657. [PMID: 38741765 PMCID: PMC11089203 DOI: 10.3389/fmed.2024.1370657] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2024] [Accepted: 04/01/2024] [Indexed: 05/16/2024] Open
Abstract
Introduction Multiple targets are considered as the causes of ambient fine particulate matter [aerodynamic diameters of < 2.5 μm (PM2.5)] induced lung function injury. Qiju granules are derived from the traditional Chinese medicine (TCM) formula known as Qi-Ju-Di-Huang-Wan (Lycium, Chrysanthemum, and Rehmannia Formula, QJDHW), which has been traditionally used to treat symptoms such as cough with phlegm, dry mouth and throat, and liver heat. This treatment approach involves attenuating inflammation, oxidative stress, and fibrosis response. This study investigated the effects of Qiju granules on protecting lung function against PM2.5 exposure in a clinical trial. Methods A randomized, double-blinded, and placebo-controlled trial was performed among 47 healthy college students in Hangzhou, Zhejiang Province in China. The participants were randomly assigned to the Qiju granules group or the control group based on gender. Clinical follow-ups were conducted once every 2 weeks during a total of 4 weeks of intervention. Real-time monitoring of PM2.5 concentrations in the individually exposed participants was carried out. Data on individual characteristics, heart rate (HR), blood pressure (BP), and lung function at baseline and during the follow-ups were collected. The effects of PM2.5 exposure on lung function were assessed within each group using linear mixed-effect models. Results In total, 40 eligible participants completed the scheduled follow-ups. The average PM2.5 level was found to be 64.72 μg/m3 during the study period. A significant negative correlation of lung function with PM2.5 exposure concentrations was observed, and a 1-week lag effect was observed. Forced expiratory volume in one second (FEV1), peak expiratory flow (PEF), maximal mid-expiratory flow (MMEF), forced expiratory flow at 75% of forced vital capacity (FVC) (FEF75), forced expiratory flow at 50% of FVC (FEF50), and forced expiratory flow at 25% of FVC (FEF25) were significantly decreased due to PM2.5 exposure in the control group. Small airway function was impaired more seriously than large airway function when PM2.5 exposure concentrations were increased. In the Qiju granules group, the associations between lung function and PM2.5 exposure were much weaker, and no statistical significance was observed. Conclusion The results of the study showed that PM2.5 exposure was associated with reduced lung function. Qiju granules could potentially be effective in protecting lung functions from the adverse effects of PM2.5 exposure. Clinical Trial Registration identifier: ChiCTR1900021235.
Collapse
Affiliation(s)
- Rucheng Chen
- School of Public Health, Zhejiang Chinese Medical University, Hangzhou, China
- Zhejiang International Science and Technology Cooperation Base of Air Pollution and Health, Hangzhou, China
| | - Lu Zhang
- School of Public Health, Zhejiang Chinese Medical University, Hangzhou, China
- Zhejiang International Science and Technology Cooperation Base of Air Pollution and Health, Hangzhou, China
| | - Weijia Gu
- School of Public Health, Zhejiang Chinese Medical University, Hangzhou, China
- Zhejiang International Science and Technology Cooperation Base of Air Pollution and Health, Hangzhou, China
| | - Ran Li
- School of Public Health, Zhejiang Chinese Medical University, Hangzhou, China
- Zhejiang International Science and Technology Cooperation Base of Air Pollution and Health, Hangzhou, China
| | - Huihua Hong
- First Affiliated Hospital of Zhejiang Chinese Medical University, Hangzhou, China
| | - Linshui Zhou
- First Affiliated Hospital of Zhejiang Chinese Medical University, Hangzhou, China
| | - Jinna Zhang
- School of Public Health, Zhejiang Chinese Medical University, Hangzhou, China
- Zhejiang International Science and Technology Cooperation Base of Air Pollution and Health, Hangzhou, China
| | - Yixuan Wang
- School of Public Health, Zhejiang Chinese Medical University, Hangzhou, China
- Zhejiang International Science and Technology Cooperation Base of Air Pollution and Health, Hangzhou, China
| | - Ping Ni
- First Affiliated Hospital of Zhejiang Chinese Medical University, Hangzhou, China
| | - Shuqin Xu
- First Affiliated Hospital of Zhejiang Chinese Medical University, Hangzhou, China
| | - Zhen Wang
- First Affiliated Hospital of Zhejiang Chinese Medical University, Hangzhou, China
| | - Qinghua Sun
- School of Public Health, Zhejiang Chinese Medical University, Hangzhou, China
- Zhejiang International Science and Technology Cooperation Base of Air Pollution and Health, Hangzhou, China
| | - Cuiqing Liu
- School of Public Health, Zhejiang Chinese Medical University, Hangzhou, China
- Zhejiang International Science and Technology Cooperation Base of Air Pollution and Health, Hangzhou, China
| | - Junchao Yang
- First Affiliated Hospital of Zhejiang Chinese Medical University, Hangzhou, China
| |
Collapse
|
2
|
Durán Del Amor MDM, Baeza Caracena A, Esquembre F, Llorens Pascual Del Riquelme M. New Methodology to Evaluate and Optimize Indoor Ventilation Based on Rapid Response Sensors. SENSORS (BASEL, SWITZERLAND) 2024; 24:1657. [PMID: 38475193 DOI: 10.3390/s24051657] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2024] [Revised: 02/24/2024] [Accepted: 02/28/2024] [Indexed: 03/14/2024]
Abstract
The recent pandemic increased attention to the need for appropriated ventilation and good air quality as efficient measures to achieve safe and healthy indoor air. This work provides a novel methodology for continuously evaluating ventilation in public areas using modern rapid response sensors (RRS). This methodology innovatively assesses the ventilation of a space by combining a quantitative estimation of the real air exchange in the space-obtained from CO2 experimental RRS measurements and the characteristics of and activity in the space-and indoor and outdoor RRS measurements of other pollutants, with healthy recommendations from different organisations. The methodology allows space managers to easily evaluate, in a continuous form, the appropriateness of their ventilation strategy, thanks to modern RRS measurements and direct calculations (implemented here in a web app), even in situations of full activity. The methodology improves on the existing standards, which imply the release of tracer gases and expert intervention, and could also be used to set a control system that measures continuously and adapts the ventilation to changes in indoor occupancy and activity, guaranteeing safe and healthy air in an energy-efficient way. Sample public concurrence spaces with different conditions are used to illustrate the methodology.
Collapse
Affiliation(s)
- María Del Mar Durán Del Amor
- Department of Chemical Engineering, Faculty of Chemistry, Campus de Espinardo, University of Murcia, 30100 Murcia, Spain
| | - Antonia Baeza Caracena
- Department of Chemical Engineering, Faculty of Chemistry, Campus de Espinardo, University of Murcia, 30100 Murcia, Spain
| | - Francisco Esquembre
- Department of Mathematics, Faculty of Mathematics, Campus de Espinardo, University of Murcia, 30100 Murcia, Spain
| | | |
Collapse
|
3
|
Lee D, Kim Y, Hong KJ, Lee G, Kim HJ, Shin D, Han B. Strategies for Effective Management of Indoor Air Quality in a Kindergarten: CO 2 and Fine Particulate Matter Concentrations. TOXICS 2023; 11:931. [PMID: 37999583 PMCID: PMC10674382 DOI: 10.3390/toxics11110931] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2023] [Revised: 10/28/2023] [Accepted: 11/14/2023] [Indexed: 11/25/2023]
Abstract
The educational and play-related activities of children proceed mainly indoors in a kindergarten. High concentrations of indoor PM2.5 and CO2 have been linked to various harmful effects on children, considerably impacting their educational outcomes in kindergarten. In this study, we explore different scenarios involving the operation of mechanical ventilation systems and air purifiers in kindergartens. Using numerical models to analyze indoor CO2 and PM2.5 concentration, we aim to optimize strategies that effectively reduce these harmful pollutants. We found that the amount of ventilation required to maintain good air quality, per child, was approximately 20.4 m3/h. However, we also found that as the amount of ventilation increased, so did the concentration of indoor PM2.5; we found that this issue can be resolved using a high-grade filter (i.e., a MERV 13 grade filter with a collection efficiency of 75%). This study provides a scientific basis for reducing PM2.5 concentrations in kindergartens, while keeping CO2 levels low.
Collapse
Affiliation(s)
- Doyeon Lee
- Department of Sustainable Environment Research, Korea Institute of Machinery & Materials, Daejeon 34103, Republic of Korea (H.-J.K.)
- Department of Mechanical Engineering, University of Science and Technology, Daejeon 34113, Republic of Korea
| | - Younghun Kim
- Department of Sustainable Environment Research, Korea Institute of Machinery & Materials, Daejeon 34103, Republic of Korea (H.-J.K.)
- Department of Mechanical Engineering, Yonsei University, Seoul 03722, Republic of Korea
| | - Kee-Jung Hong
- Department of Sustainable Environment Research, Korea Institute of Machinery & Materials, Daejeon 34103, Republic of Korea (H.-J.K.)
| | - Gunhee Lee
- Department of Sustainable Environment Research, Korea Institute of Machinery & Materials, Daejeon 34103, Republic of Korea (H.-J.K.)
| | - Hak-Joon Kim
- Department of Sustainable Environment Research, Korea Institute of Machinery & Materials, Daejeon 34103, Republic of Korea (H.-J.K.)
- Department of Mechanical Engineering, University of Science and Technology, Daejeon 34113, Republic of Korea
| | - Dongho Shin
- Department of Sustainable Environment Research, Korea Institute of Machinery & Materials, Daejeon 34103, Republic of Korea (H.-J.K.)
| | - Bangwoo Han
- Department of Sustainable Environment Research, Korea Institute of Machinery & Materials, Daejeon 34103, Republic of Korea (H.-J.K.)
- Department of Mechanical Engineering, University of Science and Technology, Daejeon 34113, Republic of Korea
| |
Collapse
|
4
|
Tapia-Brito E, Riffat J, Wang Y, Wang Y, Ghaemmaghami AM, Coleman CM, Erdinç MT, Riffat S. Experimental study of the purification performance of a MopFan-based photocatalytic air cleaning system. BUILDING AND ENVIRONMENT 2023; 240:110422. [PMID: 37251109 PMCID: PMC10186849 DOI: 10.1016/j.buildenv.2023.110422] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/05/2023] [Revised: 04/29/2023] [Accepted: 05/15/2023] [Indexed: 05/31/2023]
Abstract
Severe acute respiratory syndrome coronavirus (SARS-CoV)-2, the virus that causes the coronavirus disease (COVID)-19, is primarily transmitted through respiratory droplets which linger in enclosed spaces, often exacerbated by HVAC systems. Although research to improve HVAC handling of SARS-CoV-2 is progressing, currently installed HVAC systems cause problems because they recirculate air and use ineffective filters against virus. This paper details the process of developing a novel method of eliminating air pollutants and suspended pathogens in enclosed spaces using Photocatalytic Oxidation (PCO) technology. It has been previously employed to remove organic contaminants and compounds from air streams using the irradiation of titanium dioxide (TiO2) surfaces with ultraviolet (UV) lights causing the disintegration of organic compounds by reactions with oxygen (O) and hydroxyl radicals (OH). The outcome was two functional prototypes that demonstrate the operation of PCO-based air purification principle. These prototypes comprise a novel TiO2 coated fibre mop system, which provide very large surface area for UV irradiation. Four commercially accessible materials were used for the construction of the mop: Tampico, Brass, Coco, and Natural synthetic. Two types of UV lights were used: 365 nm (UVA) and 270 nm (UVC). A series of tests were conducted that proved the prototype's functionality and its efficiency in lowering volatile organic compounds (VOCs) and formaldehyde (HCHO). The results shown that a MopFan with rotary mop constructed with Coco fibres and utilising UVC light achieves the best VOC and HCHO purification performance. Within 2 h, this combination lowered HCHO by 50% and VOCs by 23% approximately.
Collapse
Affiliation(s)
- Emmanuel Tapia-Brito
- Department of Architecture and Built Environment, University of Nottingham, University Park, Nottingham, NG7 2RD, UK
| | - James Riffat
- Department of Architecture and Built Environment, University of Nottingham, University Park, Nottingham, NG7 2RD, UK
| | - Yixin Wang
- Department of Architecture and Built Environment, University of Nottingham, University Park, Nottingham, NG7 2RD, UK
| | - Yuhao Wang
- Department of Architecture and Built Environment, University of Nottingham, University Park, Nottingham, NG7 2RD, UK
| | - Amir M Ghaemmaghami
- Immunology & Immuno-bioengineering Group, School of Life Sciences, University of Nottingham, University Park, Nottingham, NG7 2RD, UK
| | - Christopher M Coleman
- School of Life Sciences, University of Nottingham, Queen's Medical Centre, Nottingham, NG7 2UH, UK
| | - Mehmet T Erdinç
- Department of Mechanical Engineering, Tarsus University, Tarsus, Mersin, 33400, Turkey
| | - Saffa Riffat
- Department of Architecture and Built Environment, University of Nottingham, University Park, Nottingham, NG7 2RD, UK
| |
Collapse
|
5
|
Rey-Hernández JM, Arroyo-Gómez Y, San José-Alonso JF, Rey-Martínez FJ. Assessment of natural ventilation strategy to decrease the risk of COVID 19 infection at a rural elementary school. Heliyon 2023; 9:e18271. [PMID: 37539099 PMCID: PMC10393631 DOI: 10.1016/j.heliyon.2023.e18271] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2022] [Revised: 07/07/2023] [Accepted: 07/13/2023] [Indexed: 08/05/2023] Open
Abstract
Natural ventilation in low-budget elementary schools is the main focus to ensure the health and comfort of its occupants, specifically when looking at the global pandemic related to SARS-COV-2. This paper presents an experimental and novel study of natural ventilation in a public elementary school (Los Zumacales), with a particularly low economic budget. The study was carried out during the winter months of the Covid 19 pandemic. The school is located in the rural area of Castilla y León (North-Western Spain) far from high traffic roads. In this study, a methodology of measuring CO2 concentration was applied in nine classrooms in a school. The experimental study shows the level of natural ventilation in each classroom, expressed in Air Changes per Hour (ACH), using the Decay CO2 concentration method. The method is proven by comparing the experimental values of the obtained ACH with those determined by the most powerful methods to achieve appropriate ventilation levels. Thus, ensuring health protection protocol in rural schools, against the COVID 19 pandemic. Harvard guide and Spanish regulations (RITE), two widely recognized methods have been used together with the experimentally obtained standard by Rey et al. Only one classroom showed a value lower than 3 indicating poor ventilation. In this study, the degree of thermal comfort in the nine classrooms were also analyzed according to the EN15251 standard. An average indoor temperature of approximately 19 °C was obtained, and the relative humidity was stable and correct according to Spanish regulations. In addition, the risk of infection in each classroom was estimated following the international method recommended by the federation of European Heating, Ventilation, and Air Conditioning Associations (REHVA). The probability of infection in all the cases studied was less than 14%. Therefore, this study provides a strong response against infections illnesses, such as Covid 19, in educational buildings where economic budgets of their facilities are low in both, maintenance and investment.
Collapse
Affiliation(s)
- Javier M. Rey-Hernández
- Department of Mechanical Engineering, Fluid Mechanics and Thermal Engines, Engineering School, University of Málaga (UMa), 29014 Málaga, Spain
- Thermotechnology Consolidated Research Unit (UIC 053), University of Valladolid, Spain
- Energetics Research Group (TEP139), University of Málaga, Spain
- Institute of Advanced Production Technologies (ITAP), Spain
| | - Yolanda Arroyo-Gómez
- Department of Energy and Fluid Mechanics, School of Engineering (EII), University of Valladolid (UVa), 47002 Valladolid, Spain
- Thermotechnology Consolidated Research Unit (UIC 053), University of Valladolid, Spain
- Institute of Advanced Production Technologies (ITAP), Spain
| | - Julio F. San José-Alonso
- Department of Energy and Fluid Mechanics, School of Engineering (EII), University of Valladolid (UVa), 47002 Valladolid, Spain
- Thermotechnology Consolidated Research Unit (UIC 053), University of Valladolid, Spain
- Institute of Advanced Production Technologies (ITAP), Spain
| | - Francisco J. Rey-Martínez
- Department of Energy and Fluid Mechanics, School of Engineering (EII), University of Valladolid (UVa), 47002 Valladolid, Spain
- Thermotechnology Consolidated Research Unit (UIC 053), University of Valladolid, Spain
- Institute of Advanced Production Technologies (ITAP), Spain
| |
Collapse
|
6
|
Nguyen AV, Van Vu T, Pham CLT, Nguyen VN, Ta NT, Hoang AQ, Minh TB, Tran TM. Widespread distribution of phthalic acid esters in indoor and ambient air samples collected from Hanoi, Vietnam. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:63175-63184. [PMID: 36959402 DOI: 10.1007/s11356-023-26558-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2022] [Accepted: 03/15/2023] [Indexed: 05/10/2023]
Abstract
In the present study, distribution characteristics of ten typical phthalic acid esters (PAEs) were investigated in 90 air samples collected from the urban areas in Hanoi, Vietnam from May to August 2022. The total concentrations of PAEs in indoor and ambient air samples were in the range of 320-4770 ng/m3 and 35.9-133 ng/m3, respectively. Total concentrations of PAEs in indoor air were about one order of magnitude higher than those in ambient air. Among PAEs studied, di-(2-ethyl)hexyl phthalate (DEHP) was measured at the highest levels in all air samples, followed by di-n-octyl phthalate (DnOP) and di-n-butyl phthalate (DnBP). The PAEs concentrations in air samples collected from laboratories at nighttime were significantly higher than those during daytime (p < 0.05). Meanwhile, the distributions of PAEs in various micro-environments in the same house are no statistically significant difference. The median exposure doses of PAEs through inhalation for adults and children were 248 and 725 ng/kg-bw/d, respectively. These exposure levels were still lower than the respective reference doses (RfD) proposed by the US EPA for selected compounds such as diethyl phthalate (DEP), DnBP, and DEHP.
Collapse
Affiliation(s)
- Anh Viet Nguyen
- University of Science, Vietnam National University, Hanoi, 19 Le Thanh Tong, Hanoi, Vietnam
- Vietnam Institute of Industrial Chemistry, 2 Pham Ngu Lao, Hoan Kiem, Hanoi, Vietnam
| | - Tu Van Vu
- University of Science, Vietnam National University, Hanoi, 19 Le Thanh Tong, Hanoi, Vietnam
- Institute of Environmental Technology, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet Road, Cau Giay, Hanoi, Vietnam
| | - Chi Linh Thi Pham
- University of Science, Vietnam National University, Hanoi, 19 Le Thanh Tong, Hanoi, Vietnam
| | - Viet Ngoc Nguyen
- Vietnam Institute of Industrial Chemistry, 2 Pham Ngu Lao, Hoan Kiem, Hanoi, Vietnam
| | - Nguyen Thuy Ta
- Institute of Chemistry, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet Road, Cau Giay, Hanoi, Vietnam
| | - Anh Quoc Hoang
- University of Science, Vietnam National University, Hanoi, 19 Le Thanh Tong, Hanoi, Vietnam
| | - Tu Binh Minh
- University of Science, Vietnam National University, Hanoi, 19 Le Thanh Tong, Hanoi, Vietnam
| | - Tri Manh Tran
- University of Science, Vietnam National University, Hanoi, 19 Le Thanh Tong, Hanoi, Vietnam.
| |
Collapse
|
7
|
Rawat N, Kumar P. Interventions for improving indoor and outdoor air quality in and around schools. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 858:159813. [PMID: 36411671 DOI: 10.1016/j.scitotenv.2022.159813] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2022] [Revised: 10/14/2022] [Accepted: 10/25/2022] [Indexed: 06/16/2023]
Abstract
Students spend nearly one third of their typical day in the school environment, where they may be exposed to harmful air pollutants. A consolidated knowledge base of interventions to reduce this exposure is required for making informed decisions on their implementation and wider uptake. We attempt to fill this knowledge gap by synthesising the existing scientific literature on different school-based air pollution exposure interventions, their efficiency, suitability, and limitations. We assessed technological (air purifiers, HVAC - Heating Ventilation and Air Conditioning etc.), behavioural, physical barriers, structural, school-commute and policy and regulatory interventions. Studies suggest that the removal efficiency of air purifiers for PM2.5, PM10, PM1 and BC can be up to 57 %, 34 %, 70 % and 58 %, respectively, depending on the air purification technology compared with control levels in classroom. The HVAC system combined with high efficiency filters has BC, PM10 and PM2.5 removal efficiency up to 97 %, 34 % and 30 %, respectively. Citizen science campaigns are effective in reducing the indoor air pollutants' exposure up to 94 %. The concentration of PM10, NO2, O3, BC and PNC can be reduced by up to 60 %, 59 %, 16 %, 63 % and 77 %, respectively as compared to control conditions, by installing green infrastructure (GI) as a physical barrier. School commute interventions can reduce NO2 concentration by up to 23 %. The in-cabin concentration reduction of up to 77 % for PM2.5, 43 % for PNC, 89 % for BC, 74 % for PM10 and 75 % for NO2, along with 94 % reduction in tailpipe emission of total particles, can be achieved using clean fuels and retrofits. No stand-alone method is found as the absolute solution for controlling pollutants exposure, their combined application can be effective in most of the scenarios. More research is needed on assessing combined interventions, and their operational synchronisation for getting the optimum results.
Collapse
Affiliation(s)
- Nidhi Rawat
- Global Centre for Clean Air Research (GCARE), School of Sustainability, Civil and Environmental Engineering, Faculty of Engineering and Physical Sciences, University of Surrey, Guildford GU2 7XH, United Kingdom
| | - Prashant Kumar
- Global Centre for Clean Air Research (GCARE), School of Sustainability, Civil and Environmental Engineering, Faculty of Engineering and Physical Sciences, University of Surrey, Guildford GU2 7XH, United Kingdom.
| |
Collapse
|
8
|
Fernandes A, Ubalde-López M, Yang TC, McEachan RRC, Rashid R, Maitre L, Nieuwenhuijsen MJ, Vrijheid M. School-Based Interventions to Support Healthy Indoor and Outdoor Environments for Children: A Systematic Review. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2023; 20:ijerph20031746. [PMID: 36767121 PMCID: PMC9914556 DOI: 10.3390/ijerph20031746] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2022] [Revised: 01/13/2023] [Accepted: 01/15/2023] [Indexed: 05/25/2023]
Abstract
Environmental exposures are associated with children's health. Schools are often urban exposure 'hotspots' for pollution, noise, lack of green space and un-walkable built environments. The aim of this systematic review was to explore the impact of school-based interventions on the modification of indoor and outdoor stressors related to the built and natural environment on children's exposure and health. A systematic review of seven databases was performed. We included quantitative studies on children aged 5-12, which reported intervention delivered within school settings aimed at addressing key environmental exposures including air pollution, green spaces, traffic noise or active travel; and reported physical and mental health, physical activity or active travel behavior. The quality of studies was assessed and interventions were described using a standardized framework. A narrative synthesis approach was used to describe the findings. Thirty-nine papers were included on three main intervention types: improve indoor air quality by the increase of ventilation rates in classrooms; increase children's green time or greening schools, and multicomponent interventions to increase active travel to school by changes in pedestrian facilities. No eligible intervention to reduce traffic noise at school was found. Increasing ventilation rates improved short-term indoor air quality in classrooms, but the effect on cognitive performance was inconsistent. Greening schools and increasing children's green time have consistent positive effects on cognition and physical activity, but not in behavior. Multi-component interventions can increase walking and cycling after three years. Overall, the studies were rated as having poor quality owing to weak study designs. We found modest evidence that school-based built and natural environment interventions can improve children's exposure and health.
Collapse
Affiliation(s)
- Amanda Fernandes
- ISGlobal, Barcelona Institute for Global Health, 08003 Barcelona, Spain
- Universitat Pompeu Fabra (UPF), 08003 Barcelona, Spain
- CIBER Epidemiología y Salud Pública (CIBERESP), 28029 Madrid, Spain
| | - Mònica Ubalde-López
- ISGlobal, Barcelona Institute for Global Health, 08003 Barcelona, Spain
- Universitat Pompeu Fabra (UPF), 08003 Barcelona, Spain
- CIBER Epidemiología y Salud Pública (CIBERESP), 28029 Madrid, Spain
| | - Tiffany C. Yang
- Bradford Institute for Health Research, Bradford Teaching Hospitals NHS Foundation Trust, Bradford Royal Infirmary, Bradford BD9 6RJ, UK
| | - Rosemary R. C. McEachan
- Bradford Institute for Health Research, Bradford Teaching Hospitals NHS Foundation Trust, Bradford Royal Infirmary, Bradford BD9 6RJ, UK
| | - Rukhsana Rashid
- Bradford Institute for Health Research, Bradford Teaching Hospitals NHS Foundation Trust, Bradford Royal Infirmary, Bradford BD9 6RJ, UK
| | - Léa Maitre
- ISGlobal, Barcelona Institute for Global Health, 08003 Barcelona, Spain
- Universitat Pompeu Fabra (UPF), 08003 Barcelona, Spain
- CIBER Epidemiología y Salud Pública (CIBERESP), 28029 Madrid, Spain
| | - Mark J. Nieuwenhuijsen
- ISGlobal, Barcelona Institute for Global Health, 08003 Barcelona, Spain
- Universitat Pompeu Fabra (UPF), 08003 Barcelona, Spain
- CIBER Epidemiología y Salud Pública (CIBERESP), 28029 Madrid, Spain
| | - Martine Vrijheid
- ISGlobal, Barcelona Institute for Global Health, 08003 Barcelona, Spain
- Universitat Pompeu Fabra (UPF), 08003 Barcelona, Spain
- CIBER Epidemiología y Salud Pública (CIBERESP), 28029 Madrid, Spain
| |
Collapse
|
9
|
Kumar P, Rawat N, Tiwari A. Micro-characteristics of a naturally ventilated classroom air quality under varying air purifier placements. ENVIRONMENTAL RESEARCH 2023; 217:114849. [PMID: 36414109 DOI: 10.1016/j.envres.2022.114849] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2022] [Revised: 11/14/2022] [Accepted: 11/16/2022] [Indexed: 06/16/2023]
Abstract
A naturally-ventilated operational classroom was instrumented at 18 locations to assess spatial variations of classroom air pollution (CRAP), thermal comfort and ventilation indicators under 10 different scenarios (base scenario without air purifier (AP); three single AP scenarios; three scenarios with two APs at same locations; three scenarios with two APs at different locations). Unlike PM2.5, monitored PM10 and CO2 concentrations followed the diurnal occupancy profile. Highest vertical variation (38%) in CO2 was at the classroom entry zone at 40-300 cm height. CO2 increased until 225 cm before stratifying further. PM10 increased to highest levels at children sitting height (100 cm) before decreasing to adult breathing height (150 cm). Highest horizontal variations in CO2 (PM10) were 29% (22%) at 40 cm height between the entry and occupied zones. Teachers' exposure to CO2 (PM10) in breathing zone varied by up to 6% (3%); the corresponding variations across monitored locations were up to 14% (19%). Teachers' exposure to CO2 was up to 13% higher than that of children and 18% lower for PM10. Traffic emissions (PM2.5 and NOx), secondary pollutants (VOCs and O3), thermal comfort parameters and noise level in the classroom varied insignificantly among scenarios. PM10 reduction was not doubled by using two air purifiers, which were most effective when placed within the highest PM concentration zone. Cross-comparisons of scenarios showed: use of AP reduced classroom's spatial average PM10 up to 14%; PM10 was reduced by increasing the AP's filtration capacity; and AP had insignificant impact on spatial average CO2. PM10 showed a maximum reduction of 46% (teacher zone), 62% (occupied zone) and 50% (entry zone) at children's breathing height, depending on usage scenario. This study produced high-resolution data for validating the detailed numerical models for classrooms and informing decision-making on AP's placement to minimise children's exposure to CRAP and re-breathed CO2.
Collapse
Affiliation(s)
- Prashant Kumar
- Global Centre for Clean Air Research (GCARE), School of Sustainability, Civil and Environmental Engineering, Faculty of Engineering and Physical Sciences, University of Surrey, Guildford, GU2 7XH, Surrey, United Kingdom; Institute for Sustainability, University of Surrey, Guildford GU2 7XH, Surrey, United Kingdom.
| | - Nidhi Rawat
- Global Centre for Clean Air Research (GCARE), School of Sustainability, Civil and Environmental Engineering, Faculty of Engineering and Physical Sciences, University of Surrey, Guildford, GU2 7XH, Surrey, United Kingdom
| | - Arvind Tiwari
- Global Centre for Clean Air Research (GCARE), School of Sustainability, Civil and Environmental Engineering, Faculty of Engineering and Physical Sciences, University of Surrey, Guildford, GU2 7XH, Surrey, United Kingdom
| |
Collapse
|
10
|
You B, Zhou W, Li J, Li Z, Sun Y. A review of indoor Gaseous organic compounds and human chemical Exposure: Insights from Real-time measurements. ENVIRONMENT INTERNATIONAL 2022; 170:107611. [PMID: 36335895 DOI: 10.1016/j.envint.2022.107611] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2022] [Revised: 10/29/2022] [Accepted: 10/31/2022] [Indexed: 06/16/2023]
Abstract
Gaseous organic compounds, mainly volatile organic compounds (VOCs), have become a wide concern in various indoor environments where we spend the majority of our daily time. The sources, compositions, variations, and sinks of indoor VOCs are extremely complex, and their potential impacts on human health are less understood. Owing to the deployment of the state-of-the-art real-time mass spectrometry during the last two decades, our understanding of the sources, dynamic changes and chemical transformations of VOCs indoors has been significantly improved. This review aims to summarize the key findings from mass spectrometry measurements in recent indoor studies including residence, classroom, office, sports center, etc. The sources and sinks, compositions and distributions of indoor VOCs, and the factors (e.g., human activities, air exchange rate, temperature and humidity) driving the changes in indoor VOCs are discussed. The physical and chemical processes of gas-particle partitioning and secondary oxidation processes of VOCs, and their impacts on human health are summarized. Finally, the recommendations for future research directions on indoor VOCs measurements and indoor chemistry are proposed.
Collapse
Affiliation(s)
- Bo You
- State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China; College of Earth and Planetary Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Wei Zhou
- State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China
| | - Junyao Li
- State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China; College of Earth and Planetary Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Zhijie Li
- State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China; College of Earth and Planetary Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yele Sun
- State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China; College of Earth and Planetary Sciences, University of Chinese Academy of Sciences, Beijing 100049, China.
| |
Collapse
|
11
|
Azevedo A, Liddie J, Liu J, Schiff JE, Adamkiewicz G, Hart JE. Effects of portable air cleaners and A/C unit fans on classroom concentrations of particulate matter in a non-urban elementary school. PLoS One 2022; 17:e0278046. [PMID: 36454721 PMCID: PMC9714748 DOI: 10.1371/journal.pone.0278046] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2022] [Accepted: 11/08/2022] [Indexed: 12/05/2022] Open
Abstract
Given the increased use of air cleaners as a prevention measure in classrooms during the COVID-19 pandemic, this study aimed to investigate the effects of portable air cleaners with HEPA filters and window A/C fans on real-time (1 minute) concentrations of PM less than 2.5 microns (PM2.5) or less than 1 microns (PM1.0) in two classrooms in a non-urban elementary school in Rhode Island. For half of each school day, settings were randomized to "high" or "low" for the air cleaner and "on" or "off" for the fan. Descriptive statistics and linear mixed models were used to evaluate the impacts of each set of conditions on PM2.5 and PM1.0 concentrations. The mean half-day concentrations ranged from 3.4-4.1 μg/m3 for PM2.5 and 3.4-3.9 μg/m3 for PM1.0. On average, use of the fan when the air cleaner was on the low setting decreased PM2.5 by 0.53 μg/m3 [95% CI: -0.64, -0.42] and use of the filter on high (compared to low) when the fan was off decreased PM2.5 by 0.10 μg/m3 [95% CI: -0.20, 0.005]. For PM1.0, use of the fan when the air cleaner was on low decreased concentrations by 0.18 μg/m3 [95% CI: -0.36, -0.01] and use of the filter on high (compared to low) when the fan was off decreased concentrations by 0.38 μg/m3 [95% CI: -0.55, -0.21]. In general, simultaneous use of the fan and filter on high did not result in additional decreases in PM concentrations compared to the simple addition of each appliance's individual effect estimates. Our study suggests that concurrent or separate use of an A/C fan and air cleaner in non-urban classrooms with low background PM may reduce classroom PM concentrations.
Collapse
Affiliation(s)
- Alexandra Azevedo
- Department of Environmental Health, Harvard T.H. Chan School of Public Health, Boston, Massachusetts, United States of America
| | - Jahred Liddie
- Department of Environmental Health, Harvard T.H. Chan School of Public Health, Boston, Massachusetts, United States of America
| | - Jason Liu
- Department of Environmental Health, Harvard T.H. Chan School of Public Health, Boston, Massachusetts, United States of America
| | - Jessica E. Schiff
- Department of Environmental Health, Harvard T.H. Chan School of Public Health, Boston, Massachusetts, United States of America
| | - Gary Adamkiewicz
- Department of Environmental Health, Harvard T.H. Chan School of Public Health, Boston, Massachusetts, United States of America
| | - Jaime E. Hart
- Department of Environmental Health, Harvard T.H. Chan School of Public Health, Boston, Massachusetts, United States of America
- Channing Division of Network Medicine, Department of Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, Massachusetts, United States of America
| |
Collapse
|
12
|
Kim JT, Lee CW, Jung HJ, Choi HJ, Salman A, Padmajan Sasikala S, Kim SO. Application of 2D Materials for Adsorptive Removal of Air Pollutants. ACS NANO 2022; 16:17687-17707. [PMID: 36354742 DOI: 10.1021/acsnano.2c07937] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Air pollution is on the priority list of global safety issues, with the concern of fatal environmental and public health deterioration. 2D materials are potential adsorbent materials for environmental decontamination, owing to their high surface area, manageable interlayer binding, large surface-to-volume ratio, specific binding capability, and chemical, thermal, and mechanistic stability. Specifically, graphene oxide and reduced graphene oxide have been attracting attention, taking advantage of their low cost synthesis, excessive oxygen containing surface functionalities, and intrinsic aqueous dispersibility, making them desirable for the development of cost-effective, high performance air filters. Many different material designs have been proposed to expand their filtration capability, including the functionalization and integration with other metals and metal oxides, which act not only as binding agents to the target pollutants but also as antimicrobial agents. This review highlights the advantages and drawbacks of 2D materials for air filtration and summarizes the interrelationships among various strategies and the resultant filtration performance in terms of structural engineering, morphology control, and material compositions. Finally, potential future directions are suggested toward the idealized designs of 2D material based air filters.
Collapse
Affiliation(s)
- Jun Tae Kim
- National Creative Research Initiative Center for Multi-Dimensional Directed Nanoscale Assembly, Department of Materials Science and Engineering, KAIST, 291 Daehak-ro, Yuseong-gu, Daejeon 34141, Republic of Korea
| | - Chan Woo Lee
- National Creative Research Initiative Center for Multi-Dimensional Directed Nanoscale Assembly, Department of Materials Science and Engineering, KAIST, 291 Daehak-ro, Yuseong-gu, Daejeon 34141, Republic of Korea
| | - Hong Ju Jung
- National Creative Research Initiative Center for Multi-Dimensional Directed Nanoscale Assembly, Department of Materials Science and Engineering, KAIST, 291 Daehak-ro, Yuseong-gu, Daejeon 34141, Republic of Korea
| | - Hee Jae Choi
- National Creative Research Initiative Center for Multi-Dimensional Directed Nanoscale Assembly, Department of Materials Science and Engineering, KAIST, 291 Daehak-ro, Yuseong-gu, Daejeon 34141, Republic of Korea
| | - Ali Salman
- National Creative Research Initiative Center for Multi-Dimensional Directed Nanoscale Assembly, Department of Materials Science and Engineering, KAIST, 291 Daehak-ro, Yuseong-gu, Daejeon 34141, Republic of Korea
| | - Suchithra Padmajan Sasikala
- National Creative Research Initiative Center for Multi-Dimensional Directed Nanoscale Assembly, Department of Materials Science and Engineering, KAIST, 291 Daehak-ro, Yuseong-gu, Daejeon 34141, Republic of Korea
| | - Sang Ouk Kim
- National Creative Research Initiative Center for Multi-Dimensional Directed Nanoscale Assembly, Department of Materials Science and Engineering, KAIST, 291 Daehak-ro, Yuseong-gu, Daejeon 34141, Republic of Korea
| |
Collapse
|
13
|
Aldekheel M, Altuwayjiri A, Tohidi R, Jalali Farahani V, Sioutas C. The Role of Portable Air Purifiers and Effective Ventilation in Improving Indoor Air Quality in University Classrooms. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2022; 19:14558. [PMID: 36361438 PMCID: PMC9658982 DOI: 10.3390/ijerph192114558] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/05/2022] [Revised: 10/30/2022] [Accepted: 11/03/2022] [Indexed: 06/16/2023]
Abstract
In this study we investigated the effectiveness of air purifiers and in-line filters in ventilation systems working simultaneously inside various classrooms at the University of Southern California (USC) main campus. We conducted real-time measurements of particle mass (PM), particle number (PN), and carbon dioxide (CO2) concentrations in nine classrooms from September 2021 to January 2022. The measurement campaign was carried out with different configurations of the purifier (i.e., different flow rates) while the ventilation system was continuously working. Our results showed that the ventilation systems in the classrooms were adequate in providing sufficient outdoor air to dilute indoor CO2 concentrations due to the high air exchange rates (2.63-8.63 h-1). The particle penetration coefficients (P) of the investigated classrooms were very low for PM (<0.2) and PN (<0.1), with the exception of one classroom, corroborating the effectiveness of in-line filters in the ventilation systems. Additionally, the results showed that the efficiency of the air purifier exceeded 95% in capturing ultrafine and coarse particles and ranged between 82-88% for particles in the accumulation range (0.3-2 µm). The findings of this study underline the effectiveness of air purifiers and ventilation systems equipped with efficient in-line filters in substantially reducing indoor air pollution.
Collapse
Affiliation(s)
- Mohammad Aldekheel
- Department of Civil and Environmental Engineering, University of Southern California, Los Angeles, CA 90089, USA
- Department of Civil Engineering, Kuwait University, P.O. Box 5969, Kuwait City 13060, Kuwait
| | - Abdulmalik Altuwayjiri
- Department of Civil and Environmental Engineering, College of Engineering, Majmaah University, Al-Majmaah 11952, Saudi Arabia
| | - Ramin Tohidi
- Department of Civil and Environmental Engineering, University of Southern California, Los Angeles, CA 90089, USA
| | - Vahid Jalali Farahani
- Department of Civil and Environmental Engineering, University of Southern California, Los Angeles, CA 90089, USA
| | - Constantinos Sioutas
- Department of Civil and Environmental Engineering, University of Southern California, Los Angeles, CA 90089, USA
| |
Collapse
|
14
|
Zauli-Sajani S, Marchesi S, Boselli G, Broglia E, Angella A, Maestri E, Marmiroli N, Colacci A. Effectiveness of a Protocol to Reduce Children's Exposure to Particulate Matter and NO 2 in Schools during Alert Days. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2022; 19:11019. [PMID: 36078735 PMCID: PMC9517784 DOI: 10.3390/ijerph191711019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/27/2022] [Revised: 08/31/2022] [Accepted: 08/31/2022] [Indexed: 06/15/2023]
Abstract
Reducing children's exposure to air pollutants should be considered a primary goal, especially for the most vulnerable subjects. The goal of this study was to test the effectiveness of applying a protocol in the event of alert days, i.e., days with forecasted PM10 levels above the EU limit value (50 µg/m3). The test was conducted, before the onset of SARS-CoV-2 restrictions, in a classroom of a primary school in Parma (Italy)-a highly polluted area in Northern Italy. The protocol included indications for the frequency of opening windows and doors, as well as the activation of an air purifier. Teachers and students were asked to apply the protocol only in the event of alert days, while no indications were provided for non-alert days. A monitoring system measuring PM1, PM2.5, PM10, CO2, and NO2 was deployed in the classroom. Measurements of the same parameters were also performed outdoors near the school. The application of the protocol reduced the indoor/outdoor (I/O) ratio for all toxic pollutants. The reduction was also remarkable for PM10-the most critical air quality parameter in the study area (1.5 and 1.1 for non-alert and alert days, respectively). Indoor concentrations of PM10-especially during non-alert days-were often higher than outdoors, showing a major contribution from resuspension due to the movement of people and personal cloud. The protocol did not cause any increase in indoor CO2 levels. Our findings showed that the application of a ventilation protocol together with the contribution of an air purifier may represent an effective way to reduce children's exposure to air pollution during severe air pollution episodes. Considering the onset of COVID-19 and the airborne transmission of pathogens, this protocol now has more meaningful implications for children's welfare, and can be integrated with protocols designed as measures against the spread of SARS-CoV-2.
Collapse
Affiliation(s)
- Stefano Zauli-Sajani
- Regional Agency for Prevention Environment and Energy of Emilia-Romagna (Arpae), 40139 Bologna, Italy
| | - Stefano Marchesi
- Regional Agency for Prevention Environment and Energy of Emilia-Romagna (Arpae), 40139 Bologna, Italy
| | - Giuseppe Boselli
- Regional Agency for Prevention Environment and Energy of Emilia-Romagna (Arpae), 40139 Bologna, Italy
| | | | | | - Elena Maestri
- Consorzio Interuniversitario Nazionale per le Scienze Ambientali (CINSA), Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, 43124 Parma, Italy
| | - Nelson Marmiroli
- Consorzio Interuniversitario Nazionale per le Scienze Ambientali (CINSA), Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, 43124 Parma, Italy
| | - Annamaria Colacci
- Regional Agency for Prevention Environment and Energy of Emilia-Romagna (Arpae), 40139 Bologna, Italy
| |
Collapse
|
15
|
Liu Y, Tian Z, He X, Wang X, Wei H. Short-term effects of indoor and outdoor air pollution on the lung cancer morbidity in Henan Province, Central China. ENVIRONMENTAL GEOCHEMISTRY AND HEALTH 2022; 44:2711-2731. [PMID: 34403047 DOI: 10.1007/s10653-021-01072-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Accepted: 08/09/2021] [Indexed: 06/13/2023]
Abstract
Lung cancer is one of the most common cancer types and a major cause of death. The relationship between lung cancer morbidity and exposure to air pollutants is of particular concern. However, the relationship and difference in lung cancer morbidity between indoor and outdoor air pollution effects remain unclear. In this paper, the aim was to comprehensively investigate the spatial relationships between the lung cancer morbidity and indoor-outdoor air pollution in Henan based on the standard deviation ellipse, spatial autocorrelation analysis and GeoDetector. The results indicated that (1) the spatial distribution of lung cancer morbidity was related to the geomorphology, while high-morbidity areas were concentrated in the plains and basins of Central, Eastern and Southern Henan. (2) Among the selected outdoor air pollutants, PM2.5, NO2, SO2, O3 and CO were significantly correlated with the lung cancer morbidity. The degree of indoor air pollution was measured by the use of heating energy, and the proportions of coal-heating households, households with coal/biomass stoves and households with heated kangs were highly decisive in regard to the lung cancer morbidity. (3) The interaction between two factors was more notable than a single factor in explaining the lung cancer morbidity. Moreover, the interaction type was mainly nonlinear enhancement, and the proportion of households with coal/biomass stoves imposed the strongest interaction effect on the other factors.
Collapse
Affiliation(s)
- Yan Liu
- School of Geoscience and Technology, Zhengzhou University, Zhengzhou, 450000, China
- Joint Laboratory of Ecological Meteorology, Chinese Academy of Meteorological Sciences and Zhengzhou University, Zhengzhou University, Zhengzhou, 450001, Henan, China
| | - Zhihui Tian
- School of Geoscience and Technology, Zhengzhou University, Zhengzhou, 450000, China
- Joint Laboratory of Ecological Meteorology, Chinese Academy of Meteorological Sciences and Zhengzhou University, Zhengzhou University, Zhengzhou, 450001, Henan, China
| | - Xiaohui He
- School of Geoscience and Technology, Zhengzhou University, Zhengzhou, 450000, China
- Joint Laboratory of Ecological Meteorology, Chinese Academy of Meteorological Sciences and Zhengzhou University, Zhengzhou University, Zhengzhou, 450001, Henan, China
| | - Xiaolei Wang
- School of Geoscience and Technology, Zhengzhou University, Zhengzhou, 450000, China
- Joint Laboratory of Ecological Meteorology, Chinese Academy of Meteorological Sciences and Zhengzhou University, Zhengzhou University, Zhengzhou, 450001, Henan, China
| | - Haitao Wei
- School of Geoscience and Technology, Zhengzhou University, Zhengzhou, 450000, China.
- Joint Laboratory of Ecological Meteorology, Chinese Academy of Meteorological Sciences and Zhengzhou University, Zhengzhou University, Zhengzhou, 450001, Henan, China.
| |
Collapse
|
16
|
Chen R, Zhang J, Pang Y, Liu Q, Peng J, Lin X, Cao L, Gu W, Zhang L, Li R, Sun Q, Zhang R, Liu C. Qianjinweijing Decoction Protects Against Fine Particulate Matter Exposure-mediated Lung Function Disorder. Front Pharmacol 2022; 13:873055. [PMID: 35814198 PMCID: PMC9263354 DOI: 10.3389/fphar.2022.873055] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2022] [Accepted: 06/06/2022] [Indexed: 11/20/2022] Open
Abstract
Fine particulate matter (PM2.5) is well known to impair lung function. Strategies protecting against PM2.5-exerted lung dysfunction have been less investigated. Qianjinweijing decoction (QJWJ), a decoction of a herbal medicine of natural origin, has been used to treat lung disorders as it inhibits oxidation and inflammation. However, no clinical trial has yet evaluated the role of QJWJ in PM2.5-induced lung dysfunction. Therefore, we conducted a randomized, double-blind, placebo-controlled trial to assess whether QJWJ provided lung benefits against the adverse effects of PM2.5 exposure among adults. Eligible participants (n = 65) were recruited and randomized to receive QJWJ decoction (n = 32) or placebo (n = 33) for 4 weeks. The restrictive ventilatory defect (RVD), lung function parameters, and induced sputum were analyzed. The PM2.5 exposure concentration was significantly associated with the vital capacity (VC), peak expiratory flow (PEF), and forced expiratory flow at 75% of the forced vital capacity (FEF75). The negative associations between PM2.5 and the lung function parameters were eliminated in response to the QJWJ intervention. Additionally, the percentage of RVD (P = 0.018) and the proportion of eosinophils (Eo%) in induced sputum (P = 0.014) in the QJWJ group was significantly lower than that in the placebo group. This study demonstrated that QJWJ could alleviated PM2.5-induced lung dysfunction and could be a potential treatment for air pollution-related chronic respiratory disease.
Collapse
Affiliation(s)
- Rucheng Chen
- School of Public Health, Joint China-US Research Center for Environment and Pulmonary Diseases, Zhejiang Chinese Medical University, Hangzhou, China
- Zhejiang International Science and Technology Cooperation Base of Air Pollution and Health, Hangzhou, China
| | - Jinna Zhang
- School of Public Health, Joint China-US Research Center for Environment and Pulmonary Diseases, Zhejiang Chinese Medical University, Hangzhou, China
| | - Yaxian Pang
- Department of Toxicology, Hebei Medical University, Shijiazhuang, China
| | - Qingping Liu
- Department of Toxicology, Hebei Medical University, Shijiazhuang, China
| | - Jing Peng
- School of Public Health, Joint China-US Research Center for Environment and Pulmonary Diseases, Zhejiang Chinese Medical University, Hangzhou, China
| | - Xiujuan Lin
- School of Public Health, Joint China-US Research Center for Environment and Pulmonary Diseases, Zhejiang Chinese Medical University, Hangzhou, China
| | - Lingyong Cao
- School of Basic Medical Sciences, Zhejiang Chinese Medical University, Hangzhou, China
| | - Weijia Gu
- School of Public Health, Joint China-US Research Center for Environment and Pulmonary Diseases, Zhejiang Chinese Medical University, Hangzhou, China
- Zhejiang International Science and Technology Cooperation Base of Air Pollution and Health, Hangzhou, China
| | - Lu Zhang
- School of Public Health, Joint China-US Research Center for Environment and Pulmonary Diseases, Zhejiang Chinese Medical University, Hangzhou, China
- Zhejiang International Science and Technology Cooperation Base of Air Pollution and Health, Hangzhou, China
| | - Ran Li
- School of Public Health, Joint China-US Research Center for Environment and Pulmonary Diseases, Zhejiang Chinese Medical University, Hangzhou, China
- Zhejiang International Science and Technology Cooperation Base of Air Pollution and Health, Hangzhou, China
| | - Qinghua Sun
- School of Public Health, Joint China-US Research Center for Environment and Pulmonary Diseases, Zhejiang Chinese Medical University, Hangzhou, China
- Zhejiang International Science and Technology Cooperation Base of Air Pollution and Health, Hangzhou, China
| | - Rong Zhang
- Department of Toxicology, Hebei Medical University, Shijiazhuang, China
- *Correspondence: Cuiqing Liu, ; Rong Zhang,
| | - Cuiqing Liu
- School of Public Health, Joint China-US Research Center for Environment and Pulmonary Diseases, Zhejiang Chinese Medical University, Hangzhou, China
- Zhejiang International Science and Technology Cooperation Base of Air Pollution and Health, Hangzhou, China
- *Correspondence: Cuiqing Liu, ; Rong Zhang,
| |
Collapse
|
17
|
Izadyar N, Miller W. Ventilation strategies and design impacts on indoor airborne transmission: A review. BUILDING AND ENVIRONMENT 2022; 218:109158. [PMID: 35573806 PMCID: PMC9075988 DOI: 10.1016/j.buildenv.2022.109158] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Revised: 04/26/2022] [Accepted: 04/29/2022] [Indexed: 06/15/2023]
Abstract
The COVID-19 outbreak has brought the indoor airborne transmission issue to the forefront. Although ventilation systems provide clean air and dilute indoor contaminated air, there is strong evidence that airborne transmission is the main route for contamination spread. This review paper aims to critically investigate ventilation impacts on particle spread and identify efficient ventilation strategies in controlling aerosol distribution in clinical and non-clinical environments. This article also examines influential ventilation design features (i.e., exhaust location) affecting ventilation performance in preventing aerosols spread. This paper shortlisted published documents for a review based on identification (keywords), pre-processing, screening, and eligibility of these articles. The literature review emphasizes the importance of ventilation systems' design and demonstrates all strategies (i.e., mechanical ventilation) could efficiently remove particles if appropriately designed. The study highlights the need for occupant-based ventilation systems, such as personalized ventilation instead of central systems, to reduce cross-infections. The literature underlines critical impacts of design features like ventilation rates and the number and location of exhausts and suggests designing systems considering airborne transmission. This review underpins that a higher ventilation rate should not be regarded as a sole indicator for designing ventilation systems because it cannot guarantee reducing risks. Using filtration and decontamination devices based on building functionalities and particle sizes can also increase ventilation performance. This paper suggests future research on optimizing ventilation systems, particularly in high infection risk spaces such as multi-storey hotel quarantine facilities. This review contributes to adjusting ventilation facilities to control indoor aerosol transmission.
Collapse
Affiliation(s)
- Nima Izadyar
- School of Built Environment, College of Engineering and Science, Victoria University, Melbourne, VIC, Australia
| | - Wendy Miller
- School of Architecture & Built Environment, Science and Engineering Faculty, Queensland University of Technology (QUT), Brisbane, QLD, 4001, Australia
| |
Collapse
|
18
|
Zhu YD, Li X, Fan L, Li L, Wang J, Yang WJ, Wang L, Yao XY, Wang XL. Indoor air quality in the primary school of China-results from CIEHS 2018 study. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2021; 291:118094. [PMID: 34517175 DOI: 10.1016/j.envpol.2021.118094] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2021] [Revised: 08/06/2021] [Accepted: 08/31/2021] [Indexed: 06/13/2023]
Abstract
Indoor air quality ((IAQ) in classrooms was associated with the daily exposure of school-age children who are particularly vulnerable to air pollutants exposure, while few data exist to evaluate classroom indoor air quality nationwide in China. The subsample of the CIEHS 2018 study was performed in 66 classrooms of 22 primary schools nationwide in China. Temperature, relative humidity, PM2.5, PM10, CO2, CO, formaldehyde concentrations, bacteria and fungi were detected in all classrooms by using the instruments that meet the specified accuracy. The ratios of indoor to outdoor (I/O) of PM2.5 were calculated in each classroom to identify whether the indoor environment the pollutants comes from outdoors. The indoor PM2.5, PM10, CO, HCHO, bacteria and fungi GM concentration are 47.40 μg/m3, 72.91 μg/m3, 0.37 mg/m3, 0.02 mg/m3, 347.51 CFU/m3 and 362.76 CFU/m3, respectively. We observed that there were 66.5%, 52.6%, 22.4%, 1.8%, and 9.6% of the classrooms that exceeded the guideline values of PM2.5, PM10, CO2, HCHO, and bacteria, respectively. It should be attention that all of the classroom's PM2.5 concentrations in Shijiazhuang and Nanning, PM10 concentrations in Nanning, CO2 concentration in Lanzhou were exceeded the suggested values. Bacteria contamination in Shijiazhuang's classrooms is also serious. All classroom CO concentrations meet the requirement. The results indicated that classroom indoor PM2.5 was significantly positively correlated with indoor PM10 and CO2, while was negative correlated with temperature, CO, and fungi. Our results suggest that indoor air pollution in classrooms was a severe problem in Chinese primary schools. It is necessary to strengthen ventilation in the classroom to improve indoor air quality. What's more, a healthy learning environment should be created for primary school students.
Collapse
Affiliation(s)
- Yuan-Duo Zhu
- China CDC Key Laboratory of Environment and Population Health, National Institute of Environmental Health, Chinese Center for Disease Control and Prevention, Beijing, 100021, China
| | - Xu Li
- China CDC Key Laboratory of Environment and Population Health, National Institute of Environmental Health, Chinese Center for Disease Control and Prevention, Beijing, 100021, China
| | - Lin Fan
- China CDC Key Laboratory of Environment and Population Health, National Institute of Environmental Health, Chinese Center for Disease Control and Prevention, Beijing, 100021, China
| | - Li Li
- China CDC Key Laboratory of Environment and Population Health, National Institute of Environmental Health, Chinese Center for Disease Control and Prevention, Beijing, 100021, China
| | - Jiao Wang
- China CDC Key Laboratory of Environment and Population Health, National Institute of Environmental Health, Chinese Center for Disease Control and Prevention, Beijing, 100021, China
| | - Wen-Jing Yang
- China CDC Key Laboratory of Environment and Population Health, National Institute of Environmental Health, Chinese Center for Disease Control and Prevention, Beijing, 100021, China
| | - Lin Wang
- China CDC Key Laboratory of Environment and Population Health, National Institute of Environmental Health, Chinese Center for Disease Control and Prevention, Beijing, 100021, China
| | - Xiao-Yuan Yao
- China CDC Key Laboratory of Environment and Population Health, National Institute of Environmental Health, Chinese Center for Disease Control and Prevention, Beijing, 100021, China
| | - Xian-Liang Wang
- China CDC Key Laboratory of Environment and Population Health, National Institute of Environmental Health, Chinese Center for Disease Control and Prevention, Beijing, 100021, China.
| |
Collapse
|
19
|
Zhang J, Zhang A, Liu D, Bian Y. Customer preferences extraction for air purifiers based on fine-grained sentiment analysis of online reviews. Knowl Based Syst 2021. [DOI: 10.1016/j.knosys.2021.107259] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
|
20
|
Stabile L, Pacitto A, Mikszewski A, Morawska L, Buonanno G. Ventilation procedures to minimize the airborne transmission of viruses in classrooms. BUILDING AND ENVIRONMENT 2021; 202:108042. [PMID: 34127877 PMCID: PMC8189751 DOI: 10.1016/j.buildenv.2021.108042] [Citation(s) in RCA: 40] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Revised: 05/04/2021] [Accepted: 06/05/2021] [Indexed: 05/13/2023]
Abstract
Reducing the transmission of SARS-CoV-2 through indoor air is the key challenge of the COVID-19 pandemic. Crowded indoor environments, such as schools, represent possible hotspots for virus transmission since the basic non-pharmaceutical mitigation measures applied so far (e.g. social distancing) do not eliminate the airborne transmission mode. There is widespread consensus that improved ventilation is needed to minimize the transmission potential of airborne viruses in schools, whether through mechanical systems or ad-hoc manual airing procedures in naturally ventilated buildings. However, there remains significant uncertainty surrounding exactly what ventilation rates are required, and how to best achieve these targets with limited time and resources. This paper uses a mass balance approach to quantify the ability of both mechanical ventilation and ad-hoc airing procedures to mitigate airborne transmission risk in the classroom environment. For naturally-ventilated classrooms, we propose a novel feedback control strategy using CO2 concentrations to continuously monitor and adjust the airing procedure. Our case studies show how such procedures can be applied in the real world to support the reopening of schools during the pandemic. Our results also show the inadequacy of relying on absolute CO2 concentration thresholds as the sole indicator of airborne transmission risk.
Collapse
Affiliation(s)
- L Stabile
- Department of Civil and Mechanical Engineering, University of Cassino and Southern Lazio, Cassino, FR, Italy
| | - A Pacitto
- Department of Civil and Mechanical Engineering, University of Cassino and Southern Lazio, Cassino, FR, Italy
| | - A Mikszewski
- International Laboratory for Air Quality and Health, Queensland University of Technology, Brisbane, Qld, Australia
| | - L Morawska
- International Laboratory for Air Quality and Health, Queensland University of Technology, Brisbane, Qld, Australia
| | - G Buonanno
- Department of Civil and Mechanical Engineering, University of Cassino and Southern Lazio, Cassino, FR, Italy
- International Laboratory for Air Quality and Health, Queensland University of Technology, Brisbane, Qld, Australia
| |
Collapse
|
21
|
Xie R, Xu Y, Yang J, Zhang S. Indoor air quality investigation of a badminton hall in humid season through objective and subjective approaches. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 771:145390. [PMID: 33545480 DOI: 10.1016/j.scitotenv.2021.145390] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Revised: 12/30/2020] [Accepted: 01/19/2021] [Indexed: 06/12/2023]
Abstract
This study investigated the indoor air quality (IAQ) during humid season in an old badminton hall, to explore the IAQ characteristics of natural ventilated sports buildings for public use. The indoor air parameters (temperature, relative humidity and air velocity) and indoor air pollutants (CO2, TVOC, PM2.5 and PM10) were measured. A subjective approach was carried out through questionnaire survey. 185 valid questionnaires were recovered, and 68.7% of the participants had exercised. Results show that the indoor air qualities obtained through objective and subjective approaches were obviously different. Indoor PM, TVOC and CO2 concentrations were normal, but 37.3% of the participants complained about the building materials' smell and 73.5% of the participants reported obvious sweaty odor. Physical activity might reduce a person's sensitivity to the environment. The participants generally felt warm and hot because of the high relative humidity. Post-exercise participants felt significantly hotter than those who did not exercise, and were generally more receptive to IAQ. The method of Fanger was employed to narrow the gap between subjective and objective approaches with a modified parameter, and to furtherly estimate the ventilation. The present study demonstrates the necessity to combine two approaches together to assess the IAQ in sports buildings.
Collapse
Affiliation(s)
- Ruoyi Xie
- Institute of Refrigeration and Cryogenics, Zhejiang University, Hangzhou, China
| | - Yiyang Xu
- Huadong Engineering Corporation Limited, Power Construction Corporation of China, Hangzhou, China
| | - Jinhui Yang
- Institute of Refrigeration and Cryogenics, Zhejiang University, Hangzhou, China
| | - Shaozhi Zhang
- Institute of Refrigeration and Cryogenics, Zhejiang University, Hangzhou, China.
| |
Collapse
|
22
|
Abstract
Indoor climate comfort is important for school buildings. Nowadays, this is a topical problem, especially in renovated buildings. Poorly ventilated school classrooms create improper conditions for classrooms. A post-occupancy study was performed in a school building in temperate climatic conditions. The evaluation was based on the results of long-term monitoring of the natural ventilation strategy and measurements of the carbon dioxide concentration in the school classroom’s indoor environment. The monitoring was carried out in an old school building that was constructed in the 1970s and compared to testing carried out in the same school classroom after the building was renovated in 2016. Surprisingly, the renovated classroom had a significantly higher concentration of CO2. It was found that this was due to the regulation of the heating system and the new airtight windows. The occupants of the renovated classroom have a maintained thermal comfort, but natural ventilation is rather neglected. A controlled ventilation strategy and installation of heat recovery units are recommended to solve these problems with the classroom’s indoor environment. Microbiological testing of the surfaces in school classrooms also shows the importance of fresh air and solar radiation access for indoor comfort.
Collapse
|
23
|
Holm SM, Miller MD, Balmes JR. Health effects of wildfire smoke in children and public health tools: a narrative review. JOURNAL OF EXPOSURE SCIENCE & ENVIRONMENTAL EPIDEMIOLOGY 2021; 31:1-20. [PMID: 32952154 PMCID: PMC7502220 DOI: 10.1038/s41370-020-00267-4] [Citation(s) in RCA: 63] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2020] [Revised: 09/07/2020] [Accepted: 09/11/2020] [Indexed: 05/20/2023]
Abstract
Wildfire smoke is an increasing environmental health threat to which children are particularly vulnerable, for both physiologic and behavioral reasons. To address the need for improved public health messaging this review summarizes current knowledge and knowledge gaps in the health effects of wildfire smoke in children, as well as tools for public health response aimed at children, including consideration of low-cost sensor data, respirators, and exposures in school environments. There is an established literature of health effects in children from components of ambient air pollution, which are also present in wildfire smoke, and an emerging literature on the effects of wildfire smoke, particularly for respiratory outcomes. Low-cost particulate sensors demonstrate the spatial variability of pollution, including wildfire smoke, where children live and play. Surgical masks and respirators can provide limited protection for children during wildfire events, with expected decreases of roughly 20% and 80% for surgical masks and N95 respirators, respectively. Schools should improve filtration to reduce exposure of our nation's children to smoke during wildfire events. The evidence base described may help clinical and public health authorities provide accurate information to families to improve their decision making.
Collapse
Affiliation(s)
- Stephanie M Holm
- Western States Pediatric Environmental Health Specialty Unit, University of California San Francisco, San Francisco, CA, USA.
- Division of Occupational and Environmental Medicine, University of California San Francisco, San Francisco, CA, USA.
- Division of Epidemiology, School of Public Health, University of California Berkeley, Berkeley, CA, USA.
- Children's Environmental Health Center, Office of Environmental Health Hazard Assessment, California Environmental Protection Agency, Oakland, CA, USA.
| | - Mark D Miller
- Western States Pediatric Environmental Health Specialty Unit, University of California San Francisco, San Francisco, CA, USA
- Division of Occupational and Environmental Medicine, University of California San Francisco, San Francisco, CA, USA
- Children's Environmental Health Center, Office of Environmental Health Hazard Assessment, California Environmental Protection Agency, Oakland, CA, USA
| | - John R Balmes
- Western States Pediatric Environmental Health Specialty Unit, University of California San Francisco, San Francisco, CA, USA
- Division of Occupational and Environmental Medicine, University of California San Francisco, San Francisco, CA, USA
- Division of Environmental Health Sciences, School of Public Health, University of California Berkeley, Berkeley, CA, USA
| |
Collapse
|
24
|
Dbouk T, Drikakis D. On airborne virus transmission in elevators and confined spaces. PHYSICS OF FLUIDS (WOODBURY, N.Y. : 1994) 2021; 33:011905. [PMID: 33790526 PMCID: PMC7984422 DOI: 10.1063/5.0038180] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Accepted: 12/14/2020] [Indexed: 05/04/2023]
Abstract
The impact of air ventilation systems on airborne virus transmission (AVT), and aerosols in general, in confined spaces is not yet understood. The recent pandemic has made it crucial to understand the limitations of ventilation systems regarding AVT. We consider an elevator as a prototypical example of a confined space and show how ventilation designs alone, regardless of cooling or heating, contribute to AVT. Air circulation effects are investigated through multiphase computational fluid dynamics, and the performance of an air purifier in an elevator for reducing AVT is assessed. We have investigated three different flow scenarios regarding the position and operation of inlets and outlets in the elevator and a fourth scenario that includes the operation of the air purifier. The position of the inlets and outlets significantly influences the flow circulation and droplet dispersion. An air purifier does not eliminate airborne transmission. The droplet dispersion is reduced when a pair of an inlet and an outlet is implemented. The overall practical conclusion is that the placement and design of the air purifier and ventilation systems significantly affect the droplet dispersion and AVT. Thus, engineering designs of such systems must take into account the flow dynamics in the confined space the systems will be installed.
Collapse
|
25
|
Che W, Li ATY, Frey HC, Tang KTJ, Sun L, Wei P, Hossain MS, Hohenberger TL, Leung KW, Lau AKH. Factors affecting variability in gaseous and particle microenvironmental air pollutant concentrations in Hong Kong primary and secondary schools. INDOOR AIR 2021; 31:170-187. [PMID: 32731301 DOI: 10.1111/ina.12725] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2020] [Revised: 07/13/2020] [Accepted: 07/13/2020] [Indexed: 06/11/2023]
Abstract
School-age children are particularly susceptible to exposure to air pollutants. To quantify factors affecting children's exposure at school, indoor and outdoor microenvironmental air pollutant concentrations were measured at 32 selected primary and secondary schools in Hong Kong. Real-time PM10 , PM2.5 , NO2, and O3 concentrations were measured in 76 classrooms and 23 non-classrooms. Potential explanatory factors related to building characteristics, ventilation practice, and occupant activities were measured or recorded. Their relationship with indoor measured concentrations was examined using mixed linear regression models. Ten factors were significantly associated with indoor microenvironmental concentrations, together accounting for 74%, 61%, 46%, and 38% of variations observed for PM2.5 , PM10 , O3, and NO2 microenvironmental concentrations, respectively. Outdoor concentration is the single largest predictor for indoor concentrations. Infiltrated outdoor air pollution contributes to 90%, 70%, 75%, and 50% of PM2.5 , PM10 , O3, and NO2 microenvironmental concentrations, respectively, in classrooms during school hours. Interventions to reduce indoor microenvironmental concentrations can be prioritized in reducing ambient air pollution and infiltration of outdoor pollution. Infiltration factors derived from linear regression models provide useful information on outdoor infiltration and help address the gap in generalizable parameter values that can be used to predict school microenvironmental concentrations.
Collapse
Affiliation(s)
- Wenwei Che
- Division of Environment and Sustainability, The Hong Kong University of Science and Technology, Hong Kong, China
| | - Alison T Y Li
- Division of Environment and Sustainability, The Hong Kong University of Science and Technology, Hong Kong, China
| | - Henry Christopher Frey
- Division of Environment and Sustainability, The Hong Kong University of Science and Technology, Hong Kong, China
- Department of Civil, Construction and Environmental Engineering, North Carolina State University, Raleigh, NC, USA
| | - Kimberly Tasha Jiayi Tang
- Division of Environment and Sustainability, The Hong Kong University of Science and Technology, Hong Kong, China
| | - Li Sun
- Division of Environment and Sustainability, The Hong Kong University of Science and Technology, Hong Kong, China
| | - Peng Wei
- Division of Environment and Sustainability, The Hong Kong University of Science and Technology, Hong Kong, China
| | - Md Shakhaoat Hossain
- Division of Environment and Sustainability, The Hong Kong University of Science and Technology, Hong Kong, China
| | - Tilman Leo Hohenberger
- Division of Environment and Sustainability, The Hong Kong University of Science and Technology, Hong Kong, China
| | - King Wai Leung
- Division of Environment and Sustainability, The Hong Kong University of Science and Technology, Hong Kong, China
| | - Alexis K H Lau
- Division of Environment and Sustainability, The Hong Kong University of Science and Technology, Hong Kong, China
- Department of Civil and Environmental Engineering, The Hong Kong University of Science and Technology, Hong Kong, China
- Institute for the Environment, The Hong Kong University of Science & Technology, Hong Kong, China
| |
Collapse
|
26
|
Research on the effect of different position on classroom ventilation in a “L” type teaching building. JOURNAL OF BUILDING ENGINEERING 2021. [PMCID: PMC7521358 DOI: 10.1016/j.jobe.2020.101852] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
The ventilation effect in different places in the teaching building is different. The aim of this paper is to study the relative ventilation relationship of the rooms in “L” type middle school teaching building. Taking Xiamen in the subtropical region as a typical city, different aspect ratio for 1:1, 1:1.5 and 1:2 were set as variables, using the CFD simulation method. Combined and separated effects of the defined parameters on natural ventilation performance are evaluated using the ratio of age of air area as criteria. The result shows that the “L” type teaching building ventilated condition presents several characteristics as the approaching wind direction changed. Corner, long wing and short wing of building have some influences on the wind environment for classrooms. In addition, different aspect ratio “L” type buildings correspond to different optimal inlet wind angles. The research results in this paper can help architects to design buildings more scientifically and reasonably. Ventilation performance in different position classrooms are different. The best inlet wind direction locates in the range of 120。 to 150。For 1:1 L type building. The best wind angles for classroom ventilation of “1:1.5” type teaching building is from 330° to 60°. The best inlet wind angles for classroom ventilation of “1:2” type teaching building is from 90° to 240°. For LW side, the closer to inlet wind, the bigger wind pressure of classroom in directions 0°–60°, 120°–180°, 270°–360°.
Collapse
|
27
|
Shen H, Liu B, Chen Y, Zhu X, Yun X, Meng W, Lu C, Shen G, Hu Y, Russell AG, Smith KR, Tao S. Individual and population level protection from particulate matter exposure by wearing facemasks. ENVIRONMENT INTERNATIONAL 2021; 146:106026. [PMID: 33129002 DOI: 10.1016/j.envint.2020.106026] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2020] [Revised: 07/26/2020] [Accepted: 07/31/2020] [Indexed: 06/11/2023]
Abstract
Because of the severe air pollution in northern China, facemasks have gained popularity in this area in recent years. Although the results of previous studies have shown the effectiveness of wearing facemasks for intercepting particles, the individual differences and the overall health benefits of wearing facemasks have not been comprehensively documented. In this study, using both model and personal tests under various conditions, we test eight major brands of facemasks for their removal efficiencies (REs) of particulate matter (PM) in six size ranges (from 0.3 μm to >10 μm). The results are used to assess the overall exposure reduction at the individual and population levels in Beijing. We find significant differences in REs among PM sizes, facemask brands, pollution levels, and genders. Combining the information on the usage of various brands, facemask wearing rates, and PM2.5 concentrations in the ambient and indoor air in this area, we evaluate the overall effect of facemask wearing on PM2.5 exposure reduction. It is quantitatively demonstrated that because people spend most time indoors, facemask protection is limited. For facemask wearers, the overall exposure can be reduced by less than 20%, whereas the reduction rate is as low as 2.4 ± 1.6% for the entire adult populations even in the year with the highest level of pollution with an annual mean PM2.5 concentration of 102 ± 98 μg∙m-3. As a strategy of self-protection from long-term exposure to particulate matter, wearing facemasks outdoors is inferior to the installation of indoor air purifiers.
Collapse
Affiliation(s)
- Huizhong Shen
- College of Urban and Environmental Sciences, Laboratory for Earth Surface Processes, Sino-French Institute for Earth System Science, Peking University, Beijing 100871, China; School of Civil & Environmental Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA
| | - Boyu Liu
- College of Urban and Environmental Sciences, Laboratory for Earth Surface Processes, Sino-French Institute for Earth System Science, Peking University, Beijing 100871, China
| | - Yilin Chen
- College of Urban and Environmental Sciences, Laboratory for Earth Surface Processes, Sino-French Institute for Earth System Science, Peking University, Beijing 100871, China; School of Civil & Environmental Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA
| | - Xi Zhu
- College of Urban and Environmental Sciences, Laboratory for Earth Surface Processes, Sino-French Institute for Earth System Science, Peking University, Beijing 100871, China
| | - Xiao Yun
- College of Urban and Environmental Sciences, Laboratory for Earth Surface Processes, Sino-French Institute for Earth System Science, Peking University, Beijing 100871, China
| | - Wenjun Meng
- College of Urban and Environmental Sciences, Laboratory for Earth Surface Processes, Sino-French Institute for Earth System Science, Peking University, Beijing 100871, China
| | - Cengxi Lu
- College of Urban and Environmental Sciences, Laboratory for Earth Surface Processes, Sino-French Institute for Earth System Science, Peking University, Beijing 100871, China
| | - Guofeng Shen
- College of Urban and Environmental Sciences, Laboratory for Earth Surface Processes, Sino-French Institute for Earth System Science, Peking University, Beijing 100871, China
| | - Yongtao Hu
- School of Civil & Environmental Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA
| | - Armistead G Russell
- School of Civil & Environmental Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA
| | - Kirk R Smith
- Environmental Health Sciences, School of Public Health, University of California, Berkeley, CA 94720-7360, USA
| | - Shu Tao
- College of Urban and Environmental Sciences, Laboratory for Earth Surface Processes, Sino-French Institute for Earth System Science, Peking University, Beijing 100871, China.
| |
Collapse
|
28
|
Indoor Air Quality Levels in Schools: Role of Student Activities and No Activities. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2020; 17:ijerph17186695. [PMID: 32938001 PMCID: PMC7559628 DOI: 10.3390/ijerph17186695] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Revised: 09/04/2020] [Accepted: 09/11/2020] [Indexed: 01/16/2023]
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 PM2.5, 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.
Collapse
|
29
|
Effects of the Use of Air Purifier on Indoor Environment and Respiratory System among Healthy Adults. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2020; 17:ijerph17103687. [PMID: 32456250 PMCID: PMC7277583 DOI: 10.3390/ijerph17103687] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Revised: 05/15/2020] [Accepted: 05/19/2020] [Indexed: 12/19/2022]
Abstract
Air purifiers have become popular among ordinary families. However, it remains controversial whether indoor air purification improves the respiratory health of healthy adults. A randomized crossover intervention study was conducted with 32 healthy individuals. The subjects were categorized into two groups. One group continuously used true air purifiers, and the other followed with sham air purifiers for 4 weeks. Following this first intervention, all the subjects underwent a 4-week washout period and continued with the second 4-week intervention with the alternate air purifiers. We collected fine particulate matter (PM) ≤ 2.5 µm in aerodynamic diameter (PM2.5), coarse particulate matter between 2.5 and 10 µm in aerodynamic diameter (PM10–2.5) and ozone (O3). The subjects’ pulmonary function and fractional exhaled nitric oxide (FeNO) were measured during the study period. The indoor PM2.5 concentrations decreased by 11% with the true air purifiers compared to those with sham air purifiers. However, this decrease was not significant (p = 0.08). The air purification did not significantly improve the pulmonary function of the study subjects. In contrast, an increase in the indoor PM10–2.5 and O3 concentration led to a significant decrease in the forced expiratory volume in one second (FEV1.0)/forced vital capacity (FVC) and maximal mid-expiratory flow (MMEF), respectively. In conclusion, air purification slightly improved the indoor PM2.5 concentrations in ordinary homes but had no demonstrable impact on improving health.
Collapse
|
30
|
Exposure to Submicron Particles and Estimation of the Dose Received by Children in School and Non-School Environments. ATMOSPHERE 2020. [DOI: 10.3390/atmos11050485] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
In the present study, the daily dose in terms of submicron particle surface area received by children attending schools located in three different areas (rural, suburban, and urban), characterized by different outdoor concentrations, was evaluated. For this purpose, the exposure to submicron particle concentration levels of the children were measured through a direct exposure assessment approach. In particular, measurements of particle number and lung-deposited surface area concentrations at “personal scale” of 60 children were performed through a handheld particle counter to obtain exposure data in the different microenvironments they resided. Such data were combined with the time–activity pattern data, characteristics of each child, and inhalation rates (related to the activity performed) to obtain the total daily dose in terms of particle surface area. The highest daily dose was estimated for children attending the schools located in the urban and suburban areas (>1000 mm2), whereas the lowest value was estimated for children attending the school located in a rural area (646 mm2). Non-school indoor environments were recognized as the most influential in terms of children’s exposure and, thus, of received dose (>70%), whereas school environments contribute not significantly to the children daily dose, with dose fractions of 15–19% for schools located in urban and suburban areas and just 6% for the rural one. Therefore, the study clearly demonstrates that, whatever the school location, the children daily dose cannot be determined on the basis of the exposures in outdoor or school environments, but a direct assessment able to investigate the exposure of children during indoor environment is essential.
Collapse
|