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Wardlaw AJ, Rick EM, Pur Ozyigit L, Scadding A, Gaillard EA, Pashley CH. New Perspectives in the Diagnosis and Management of Allergic Fungal Airway Disease. J Asthma Allergy 2021; 14:557-573. [PMID: 34079294 PMCID: PMC8164695 DOI: 10.2147/jaa.s251709] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Accepted: 05/04/2021] [Indexed: 12/23/2022] Open
Abstract
Allergy to airway-colonising, thermotolerant, filamentous fungi represents a distinct eosinophilic endotype of often severe lung disease. This endotype, which particularly affects adult asthma, but also complicates other airway diseases and sometimes occurs de novo, has a heterogeneous presentation ranging from severe eosinophilic asthma to lobar collapse. Its hallmark is lung damage, characterised by fixed airflow obstruction (FAO), bronchiectasis and lung fibrosis. It has a number of monikers including severe asthma with fungal sensitisation (SAFS) and allergic bronchopulmonary aspergillosis/mycosis (ABPA/M), but these exclusive terms constitute only sub-sets of the condition. In order to capture the full extent of the syndrome we prefer the inclusive term allergic fungal airway disease (AFAD), the criteria for which are IgE sensitisation to relevant fungi in association with airway disease. The primary fungus involved is Aspergillus fumigatus, but a number of other thermotolerant species from several genera have been implicated. The unifying mechanism involves germination of inhaled fungal spores in the lung in the context of IgE sensitisation, leading to a persistent and vigorous eosinophilic inflammatory response in association with release of fungal proteases. Most allergenic fungi, including Alternaria and Cladosporium species, are not thermotolerant and cannot germinate in the airways so only act as aeroallergens and do not cause AFAD. Studies of the airway mycobiome have shown that A. fumigatus colonises the normal as much as the asthmatic airway, suggesting it is the tendency to become IgE-sensitised that is the critical triggering factor for AFAD rather than colonisation per se. Treatment is aimed at preventing exacerbations with glucocorticoids and increasingly by the use of anti-T2 biological therapies. Anti-fungal therapy has a limited place in management, but is an effective treatment for fungal bronchitis which complicates AFAD in about 10% of cases.
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Affiliation(s)
- Andrew J Wardlaw
- Institute for Lung Health, Department of Respiratory Sciences, College of Life Sciences, University of Leicester, and Allergy and Respiratory Medicine Service, NIHR Biomedical Research Centre: Respiratory, University Hospitals of Leicester NHS Trust, Leicester, UK
| | - Eva-Maria Rick
- Institute for Lung Health, Department of Respiratory Sciences, College of Life Sciences, University of Leicester, and Allergy and Respiratory Medicine Service, NIHR Biomedical Research Centre: Respiratory, University Hospitals of Leicester NHS Trust, Leicester, UK
| | - Leyla Pur Ozyigit
- Allergy and Respiratory Services University Hospitals of Leicester NHS Trust, Leicester, UK
| | - Alys Scadding
- Allergy and Respiratory Services University Hospitals of Leicester NHS Trust, Leicester, UK
| | - Erol A Gaillard
- Institute for Lung Health, Department of Respiratory Sciences, College of Life Sciences, Department of Paediatrics, NIHR Biomedical Research Centre: Respiratory, University Hospitals of Leicester NHS Trust, Leicester, UK
| | - Catherine H Pashley
- Institute for Lung Health, Department of Respiratory Sciences, College of Life Sciences, University of Leicester, and Allergy and Respiratory Medicine Service, NIHR Biomedical Research Centre: Respiratory, University Hospitals of Leicester NHS Trust, Leicester, UK
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2
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Dillon CF, Dillon MB. Multi-Scale Airborne Infectious Disease Transmission. Appl Environ Microbiol 2021; 87:AEM.02314-20. [PMID: 33277266 PMCID: PMC7851691 DOI: 10.1128/aem.02314-20] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Airborne disease transmission is central to many scientific disciplines including agriculture, veterinary biosafety, medicine, and public health. Legal and regulatory standards are in place to prevent agricultural, nosocomial, and community airborne disease transmission. However, the overall importance of the airborne pathway is underappreciated, e.g.,, US National Library of Medicine's Medical Subjects Headings (MESH) thesaurus lacks an airborne disease transmission indexing term. This has practical consequences as airborne precautions to control epidemic disease spread may not be taken when airborne transmission is important, but unrecognized. Publishing clearer practical methodological guidelines for surveillance studies and disease outbreak evaluations could help address this situation.To inform future work, this paper highlights selected, well-established airborne transmission events - largely cases replicated in multiple, independently conducted scientific studies. Methodologies include field experiments, modeling, epidemiology studies, disease outbreak investigations and mitigation studies. Collectively, this literature demonstrates that airborne viruses, bacteria, and fungal pathogens have the capability to cause disease in plants, animals, and humans over multiple distances - from near range (< 5 m) to continental (> 500 km) in scale. The plausibility and implications of undetected airborne disease transmission are discussed, including the notable underreporting of disease burden for several airborne transmitted diseases.
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Affiliation(s)
| | - Michael B Dillon
- Atmospheric, Earth, and Energy Division, Lawrence Livermore National Laboratory Livermore, California, USA 94551
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3
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Ferguson RMW, Neath CEE, Nasir ZA, Garcia-Alcega S, Tyrrel S, Coulon F, Dumbrell AJ, Colbeck I, Whitby C. Size fractionation of bioaerosol emissions from green-waste composting. ENVIRONMENT INTERNATIONAL 2021; 147:106327. [PMID: 33387881 DOI: 10.1016/j.envint.2020.106327] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/23/2020] [Revised: 12/04/2020] [Accepted: 12/05/2020] [Indexed: 06/12/2023]
Abstract
Particle size is a significant factor in determining the dispersal and inhalation risk from bioaerosols. Green-waste composting is a significant source of bioaerosols (including pathogens), but little is known about the distribution of specific taxa across size fractions. To characterise size fractionated bioaerosol emissions from a compost facility, we used a Spectral Intensity Bioaerosol Sensor (SIBS) to quantify total bioaerosols and qPCR and metabarcoding to quantify microbial bioaerosols. Overall, sub-micron bioaerosols predominated, but molecular analysis showed that most (>75%) of the airborne microorganisms were associated with the larger size fractions (>3.3 µm da). The microbial taxa varied significantly by size, with Bacilli dominating the larger, and Actinobacteria the smaller, size fractions. The human pathogen Aspergillus fumigatus dominated the intermediate size fractions (>50% da 1.1-4.7 µm), indicating that it has the potential to disperse widely and once inhaled may penetrate deep into the respiratory system. The abundance of Actinobacteria (>60% at da < 2.1 µm) and other sub-micron bioaerosols suggest that the main health effects from composting bioaerosols may come from allergenic respiratory sensitisation rather than directly via infection. These results emphasise the need to better understand the size distributions of bioaerosols across all taxa in order to model their dispersal and to inform risk assessments of human health related to composting facilities.
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Affiliation(s)
- Robert M W Ferguson
- School of Life Sciences, University of Essex, Wivenhoe Park, Colchester CO4 3SQ, UK
| | - Charlotte E E Neath
- School of Life Sciences, University of Essex, Wivenhoe Park, Colchester CO4 3SQ, UK; School of Applied Sciences, University of South Wales, Cemetery Road, Glyntaff, Pontypridd CF37 4BD, UK
| | - Zaheer A Nasir
- Cranfield University, School of Water, Energy and Environment, Cranfield MK43 0AL, UK
| | - Sonia Garcia-Alcega
- Cranfield University, School of Water, Energy and Environment, Cranfield MK43 0AL, UK
| | - Sean Tyrrel
- Cranfield University, School of Water, Energy and Environment, Cranfield MK43 0AL, UK
| | - Frederic Coulon
- Cranfield University, School of Water, Energy and Environment, Cranfield MK43 0AL, UK
| | - Alex J Dumbrell
- School of Life Sciences, University of Essex, Wivenhoe Park, Colchester CO4 3SQ, UK
| | - Ian Colbeck
- School of Life Sciences, University of Essex, Wivenhoe Park, Colchester CO4 3SQ, UK
| | - Corinne Whitby
- School of Life Sciences, University of Essex, Wivenhoe Park, Colchester CO4 3SQ, UK.
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Nair AT. Bioaerosols in the landfill environment: an overview of microbial diversity and potential health hazards. AEROBIOLOGIA 2021; 37:185-203. [PMID: 33558785 PMCID: PMC7860158 DOI: 10.1007/s10453-021-09693-9] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Accepted: 01/19/2021] [Indexed: 05/05/2023]
Abstract
Landfilling is one of the indispensable parts of solid waste management in various countries. Solid waste disposed of in landfill sites provides nutrients for the proliferation of pathogenic microbes which are aerosolized into the atmosphere due to the local meteorology and various waste disposal activities. Bioaerosols released from landfill sites can create health issues for employees and adjoining public. The present study offers an overview of the microbial diversity reported in the air samples collected from various landfill sites worldwide. This paper also discusses other aspects, including effect of meteorological conditions on the bioaerosol concentrations, sampling techniques, bioaerosol exposure and potential health impacts. Analysis of literature concluded that landfill air is dominated by microbial dust or various pathogenic microbes like Enterobacteriaceae, Staphylococcus aureus, Clostridium perfringens, Acinetobacter calcoaceticus and Aspergillus fumigatus. The bioaerosols present in the landfill environment are of respirable sizes and can penetrate deep into lower respiratory systems and trigger respiratory symptoms and chronic pulmonary diseases. Most studies reported higher bioaerosol concentrations in spring and summer as higher temperature and relative humidity provide a favourable environment for survival and multiplication of microbes. Landfill workers involved in solid waste disposal activities are at the highest risk of exposure to these bioaerosols due to their proximity to solid waste and as they practise minimum personal safety and hygiene measures during working hours. Workers are recommended to use personal protective equipment and practise hygiene to reduce the impact of occupational exposure to bioaerosols.
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Affiliation(s)
- Abhilash T. Nair
- Department of Applied Sciences and Humanities, National Institute of Foundry and Forge Technology (NIFFT), Hatia, Ranchi, Jharkhand 834003 India
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Roca-Barcelo A, Douglas P, Fecht D, Sterrantino AF, Williams B, Blangiardo M, Gulliver J, Hayes ET, Hansell AL. Risk of respiratory hospital admission associated with modelled concentrations of Aspergillus fumigatus from composting facilities in England. ENVIRONMENTAL RESEARCH 2020; 183:108949. [PMID: 31902481 DOI: 10.1016/j.envres.2019.108949] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2019] [Revised: 11/18/2019] [Accepted: 11/18/2019] [Indexed: 06/10/2023]
Abstract
Bioaerosols have been associated with adverse respiratory-related health effects and are emitted in elevated concentrations from composting facilities. We used modelled Aspergillus fumigatus concentrations, a good indicator for bioaerosol emissions, to assess associations with respiratory-related hospital admissions. Mean daily Aspergillus fumigatus concentrations were estimated for each composting site for first full year of permit issue from 2005 onwards to 2014 for Census Output Areas (COAs) within 4 km of 76 composting facilities in England, as previously described (Williams et al., 2019). We fitted a hierarchical generalized mixed model to examine the risk of hospital admission with a primary diagnosis of (i) any respiratory condition, (ii) respiratory infections, (iii) asthma, (iv) COPD, (v) diseases due to organic dust, and (vi) Cystic Fibrosis, in relation to quartiles of Aspergillus fumigatus concentrations. Models included a random intercept for each COA to account for over-dispersion, nested within composting facility, on which a random intercept was fitted to account for clustering of the data, with adjustments for age, sex, ethnicity, deprivation, tobacco sales (smoking proxy) and traffic load (as a proxy for traffic-related air pollution). We included 249,748 respiratory-related and 3163 Cystic Fibrosis hospital admissions in 9606 COAs with a population-weighted centroid within 4 km of the 76 included composting facilities. After adjustment for confounders, no statistically significant effect was observed for any respiratory-related (Relative Risk (RR) = 0.99; 95% Confidence Interval (CI) 0.96-1.01) or for Cystic Fibrosis (RR = 1.01; 95% CI 0.56-1.83) hospital admissions for COAs in the highest quartile of exposure. Similar results were observed across all respiratory disease sub-groups. This study does not provide evidence for increased risks of respiratory-related hospitalisations for those living near composting facilities. However, given the limitations in the dispersion modelling, risks cannot be completely ruled out. Hospital admissions represent severe respiratory episodes, so further study would be needed to investigate whether bioaerosols emitted from composting facilities have impacts on less severe episodes or respiratory symptoms.
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Affiliation(s)
- Aina Roca-Barcelo
- UK Small Area Health Statistics Unit, MRC-PHE Centre for Environment and Health, School of Public Health, Imperial College London, London, W2 1PG, UK
| | - Philippa Douglas
- UK Small Area Health Statistics Unit, MRC-PHE Centre for Environment and Health, School of Public Health, Imperial College London, London, W2 1PG, UK; Population Health and Occupational Disease, National Heart and Lung Institute, Imperial College London, London, SW3 6LR, UK; Centre for Radiation, Chemical and Environmental Hazards, Public Health England, Harwell Campus, Didcot, Oxfordshire, OX11 0RQ, UK.
| | - Daniela Fecht
- UK Small Area Health Statistics Unit, MRC-PHE Centre for Environment and Health, School of Public Health, Imperial College London, London, W2 1PG, UK
| | - Anna Freni Sterrantino
- UK Small Area Health Statistics Unit, MRC-PHE Centre for Environment and Health, School of Public Health, Imperial College London, London, W2 1PG, UK
| | - Ben Williams
- Air Quality Management Resource Centre, University of the West of England, Faculty of Environment and Technology, Coldharbour Lane, Bristol, BS16 1QY, UK
| | - Marta Blangiardo
- MRC-PHE Centre for Environment and Health, Department of Epidemiology and Biostatistics, School of Public Health, Imperial College London, London, W2 1PG, UK
| | - John Gulliver
- MRC-PHE Centre for Environment and Health, Department of Epidemiology and Biostatistics, School of Public Health, Imperial College London, London, W2 1PG, UK; Centre for Environmental Health and Sustainability, University of Leicester, Leicester, LE1 7RH, UK
| | - Enda T Hayes
- Air Quality Management Resource Centre, University of the West of England, Faculty of Environment and Technology, Coldharbour Lane, Bristol, BS16 1QY, UK
| | - Anna L Hansell
- UK Small Area Health Statistics Unit, MRC-PHE Centre for Environment and Health, School of Public Health, Imperial College London, London, W2 1PG, UK; Centre for Environmental Health and Sustainability, University of Leicester, Leicester, LE1 7RH, UK; Directorate of Public Health and Primary Care, Imperial College Healthcare NHS Trust, London, W2 1NY, UK.
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6
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Ferguson RMW, Garcia‐Alcega S, Coulon F, Dumbrell AJ, Whitby C, Colbeck I. Bioaerosol biomonitoring: Sampling optimization for molecular microbial ecology. Mol Ecol Resour 2019; 19:672-690. [PMID: 30735594 PMCID: PMC6850074 DOI: 10.1111/1755-0998.13002] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2018] [Revised: 01/25/2019] [Accepted: 01/29/2019] [Indexed: 12/31/2022]
Abstract
Bioaerosols (or biogenic aerosols) have largely been overlooked by molecular ecologists. However, this is rapidly changing as bioaerosols play key roles in public health, environmental chemistry and the dispersal ecology of microbes. Due to the low environmental concentrations of bioaerosols, collecting sufficient biomass for molecular methods is challenging. Currently, no standardized methods for bioaerosol collection for molecular ecology research exist. Each study requires a process of optimization, which greatly slows the advance of bioaerosol science. Here, we evaluated air filtration and liquid impingement for bioaerosol sampling across a range of environmental conditions. We also investigated the effect of sampling matrices, sample concentration strategies and sampling duration on DNA yield. Air filtration using polycarbonate filters gave the highest recovery, but due to the faster sampling rates possible with impingement, we recommend this method for fine -scale temporal/spatial ecological studies. To prevent bias for the recovery of Gram-positive bacteria, we found that the matrix for impingement should be phosphate-buffered saline. The optimal method for bioaerosol concentration from the liquid matrix was centrifugation. However, we also present a method using syringe filters for rapid in-field recovery of bioaerosols from impingement samples, without compromising microbial diversity for high -throughput sequencing approaches. Finally, we provide a resource that enables molecular ecologists to select the most appropriate sampling strategy for their specific research question.
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Affiliation(s)
| | | | - Frederic Coulon
- School of Water, Energy and EnvironmentCranfield UniversityCranfieldUK
| | | | - Corinne Whitby
- School of Biological SciencesUniversity of EssexColchesterUK
| | - Ian Colbeck
- School of Biological SciencesUniversity of EssexColchesterUK
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7
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Williams B, Douglas P, Roca Barcelo A, Hansell AL, Hayes E. Estimating Aspergillus fumigatus exposure from outdoor composting activities in England between 2005 and 14. WASTE MANAGEMENT (NEW YORK, N.Y.) 2019; 84:235-244. [PMID: 30691898 DOI: 10.1016/j.wasman.2018.11.044] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/27/2018] [Revised: 11/27/2018] [Accepted: 11/28/2018] [Indexed: 06/09/2023]
Abstract
Bioaerosols, ubiquitous in ambient air, are released in elevated concentrations from composting facilities with open-air processing areas. However, spatial and temporal variability of bioaerosols, particularly in relation to meteorology, is not well understood. Here we model relative concentrations of Aspergillus fumigatus at each postcode-weighted centroid within 4 km of 217 composting facilities in England between 2005 and 2014. Facilities were geocoded with the aid of satellite imagery. Data from existing bioaerosol modelling literature were used to build emission profiles in ADMS. Variation in input parameters between each modelled facility was reduced to a minimum. Meteorological data for each composting facility was derived from the nearest SCAIL-Agriculture validated meteorological station. According to our results, modelled exposure risk was driven primarily by wind speed, direction and time-varying emissions factors incorporating seasonal fluctuations in compostable waste. Modelled A.fumigatus concentrations decreased rapidly from the facility boundary and plateaued beyond 1.5-2.0 km. Where multiple composting facilities were within 4 km of each other, complex exposure risk patterns were evident. More long-term bioaerosol monitoring near facilities is needed to help improve exposure estimation and therefore assessment of any health risks to local populations.
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Affiliation(s)
- B Williams
- Air Quality Management Resource Centre, University of the West of England, Faculty of Environment and Technology, Coldharbour Lane, Bristol BS16 1QY, UK.
| | - P Douglas
- UK Small Area Health Statistics Unit, MRC-PHE Centre for Environment and Health, Imperial College London, London W2 1PG, UK; Population Health and Occupational Disease, National Heart and Lung Institute, Imperial College, London SW3 6LR, UK; National Institute for Health Research Health Protection Research Unit (NIHR HPRU) in Health Impact of Environmental Hazards, Department of Epidemiology and Biostatistics, Imperial College London, London W2 1PG, UK
| | - A Roca Barcelo
- UK Small Area Health Statistics Unit, MRC-PHE Centre for Environment and Health, Imperial College London, London W2 1PG, UK; National Institute for Health Research Health Protection Research Unit (NIHR HPRU) in Health Impact of Environmental Hazards, Department of Epidemiology and Biostatistics, Imperial College London, London W2 1PG, UK
| | - A L Hansell
- UK Small Area Health Statistics Unit, MRC-PHE Centre for Environment and Health, Imperial College London, London W2 1PG, UK; National Institute for Health Research Health Protection Research Unit (NIHR HPRU) in Health Impact of Environmental Hazards, Department of Epidemiology and Biostatistics, Imperial College London, London W2 1PG, UK; Directorate of Public Health and Primary Care, Imperial College Healthcare NHS Trust, London W2 1NY, UK; Centre for Environmental Health and Sustainability, George Davies Centre University of Leicester, University Road, Leicester LE1 7RH, UK
| | - E Hayes
- Air Quality Management Resource Centre, University of the West of England, Faculty of Environment and Technology, Coldharbour Lane, Bristol BS16 1QY, UK
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Douglas P, Hayes ET, Williams WB, Tyrrel SF, Kinnersley RP, Walsh K, O'Driscoll M, Longhurst PJ, Pollard SJT, Drew GH. Use of dispersion modelling for Environmental Impact Assessment of biological air pollution from composting: Progress, problems and prospects. WASTE MANAGEMENT (NEW YORK, N.Y.) 2017; 70:22-29. [PMID: 28889991 DOI: 10.1016/j.wasman.2017.08.023] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2016] [Revised: 08/08/2017] [Accepted: 08/09/2017] [Indexed: 06/07/2023]
Abstract
With the increase in composting asa sustainable waste management option, biological air pollution (bioaerosols) from composting facilities have become a cause of increasing concern due to their potential health impacts. Estimating community exposure to bioaerosols is problematic due to limitations in current monitoring methods. Atmospheric dispersion modelling can be used to estimate exposure concentrations, however several issues arise from the lack of appropriate bioaerosol data to use as inputs into models, and the complexity of the emission sources at composting facilities. This paper analyses current progress in using dispersion models for bioaerosols, examines the remaining problems and provides recommendations for future prospects in this area. A key finding is the urgent need for guidance for model users to ensure consistent bioaerosol modelling practices.
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Affiliation(s)
- P Douglas
- UK Small Area Health Statistics Unit, MRC-PHE Centre for Environment and Health, Imperial College London, London, United Kingdom; School of Water, Energy and Environment, Cranfield University, Cranfield, Bedfordshire MK43 0AL, UK.
| | - E T Hayes
- Air Quality Management Resource Centre, University of the West of England, Faculty of Environment and Technology, Coldharbour Lane, Bristol BS16 1QY, UK.
| | - W B Williams
- Air Quality Management Resource Centre, University of the West of England, Faculty of Environment and Technology, Coldharbour Lane, Bristol BS16 1QY, UK.
| | - S F Tyrrel
- School of Water, Energy and Environment, Cranfield University, Cranfield, Bedfordshire MK43 0AL, UK.
| | - R P Kinnersley
- Environment Agency, Environment and Business Directorate, Deanery Road, Bristol BS1 5AH, UK.
| | - K Walsh
- Environment Agency, Environment and Business Directorate, Deanery Road, Bristol BS1 5AH, UK.
| | - M O'Driscoll
- Environment Agency, Air Quality Modelling Assessment Unit, Deanery Road, Bristol BS1 5AH, United Kingdom.
| | - P J Longhurst
- School of Water, Energy and Environment, Cranfield University, Cranfield, Bedfordshire MK43 0AL, UK.
| | - S J T Pollard
- School of Water, Energy and Environment, Cranfield University, Cranfield, Bedfordshire MK43 0AL, UK.
| | - G H Drew
- School of Water, Energy and Environment, Cranfield University, Cranfield, Bedfordshire MK43 0AL, UK.
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