|Wednesday, 18th April 2018|
|Ultrafine particles: two decades of research and the debate is still on!|
Lidia Morawska, Queensland University of Technology, Australia
Over recent decades, numerous research projects have investigated an array of characteristics of ultrafine particles (UFP), or more generally, particles of the lower sub-micrometre size range. There is a reasonably good scientific understanding of the particle concentration levels, modality of size distributions associated with various sources, and their spatial heterogeneity in the urban environments. However, despite the progress made, there has only been very limited progress in understanding the risk to human health posed by UFP, and therefore whether the particles should be controlled. Part of the reason relates to the challenges in conducting epidemiological studies on the impact of UFP, and lack of consistency between the outcomes of some of the studies. Is there a change to this situation on the horizon? The presentation will attempt to address this question based on recent publications and current developments.
|Air Pollution Threats to Cultural Heritage: Results from Case Studies in Italy|
Roberta Vecchi, University of Milan, Italy
The issue of conservation of the cultural heritage worldwide is strongly related to air pollution; indeed, it has been widely recognised as one of the major threats to cultural heritage both indoor and outdoor. In addition to damage due to pollutants, weathering from natural events and microclimatic conditions plays also a role in promoting and/or intensify surface damage; thus, information on both air quality and microclimate are needed to effectively evaluate conservation methods. The costs for deterioration and soiling of different materials due to air pollution are huge and the damage to cultural targets seriously endangers the European cultural heritage. This problem is particularly noteworthy in countries with major concentrations of World Heritage Sites like Italy, which– according to the latest UNESCO report (2017) – is at the top of the world heritage list. Works of art in outdoor environments are directly affected by external pollution and meteo-climatic factors, while indoor they are strongly influenced by cultural heritage management (i.e. tourists pressure regulation, air conditioning and heating systems, etc.), and by the structural characteristics of the building, which affect the indoor/outdoor exchange of external pollutants.
In this presentation, results from case studies in environments of artistic interest will be presented focusing on the importance of an integrated approach to assess air pollution threats to cultural heritage.
|From 2D to 3D – particle release of desktop printers|
Tunga Salthammer, WKI, Germany
The release of fine and ultrafine particles from printing devices and their impact on indoor air quality is still subject of ongoing discussions. In the last few years, laser printers were in the focus of scientific studies. However, 3D printing is a quickly developing and emerging technology. In this presentation particle formation and emission from operated 2D and 3D printers are described and characterized. The fundamental differences between the two processes will be discussed.
Indoor particles characteristics – what do we know about their physicochemical properties and toxicity?Aneta Wierzbicka, Lund University, Sweden.
What do we know about airborne particles in our homes? Recently, a real time aerosol mass spectrometry has been used for measurements in indoor environments, what have learned from these studies? Are we able to pinpoint major differences between particles found indoors and outdoors? Do we have enough scientific evidence to request that indoor generated particles should be included in the exposure risk assessment and epidemiological studies?
Indoor air quality issues in sport and fitness facilities
Giovanni Capelli, University of Cassino and Southern Lazio, Italy
Sport and fitness indoor facilities range from small gym rooms to big indoor venues, from swimming pools to sport halls. Different users have access to them, with different time exposure and performed activities: professional athletes, grassroots sport players, people practicing leisure time physical activities and sport event fans. Many indoor air quality issues may rise in these facilities, linked to VOCs and POMs originated from construction materials (e.g. plastics, woods and their treatment substances, etc.), cleaning and sanitation chemical substances and even human activities (e.g. sweating, trampling, etc.), impact on the planning, building, refurbishing and maintenance of the venues and their HVAC systems.
Indoor aerosol deliquescence and crystallization: a risk/opportunity for energy saving and cultural heritage conservation
Luca Ferrero, University of Milan “Bicocca”, Italy
Aerosol chemical composition determines the relative humidity at which the aerosol deliquescence (DRH) or crystallization (CRH) occurs; the aerosol ionic content, the organic fraction and insoluble inclusions can induce a variation of DRH and CRH up to ±30% of relative humidity. The CRH is lower than the DRH leading to a hysteresis cycle of aerosol hydration, whose level finally depends on the relative humidity (RH) to which an aerosol particle is exposed compared to the values of DRH and CRH in function of the RH history at a given temperature. The level of aerosol hydration impacts a wide range of aerosol properties and processes; among them the aerosol’s ability to promote ‘‘failures’’ in electronic equipment and to damage cultural heritage. Thus, aerosol hysteresis becomes crucial in corrosion studies, energy saving in data centers and heritage studies in indoor environments. This study examines an innovative approach to the indoor DRH and CRH applied to the ENI Green data center in Italy and to the Last Supper of Leonardo da Vinci to highlight the importance of indoor hygroscopicity. In this respect, the experimental measurements of both DRH and CRH were applied to the aforementioned case studies enabling to achieve an energy saving of 79 % (215 GWh of energy saved, and 78 fewer kt of equivalent CO2 emitted per year) at the ENI data center and to define the set-point thermodynamic conditions for the Last Supper.
|Thursday, 19th April 2018|
|Air quality in subway systems: room for improvement|
Teresa Moreno, IDAEA-CSIC, Spain
Subway systems can be viewed as a transport lifeline, helping to improve the quality of urban infrastructure and relieve road traffic congestion. However, one disadvantage of any underground transport system is that it operates in a confined space that may permit the accumulation of unhealthy concentrations of airborne contaminants. The main challenge with regard to improving air quality in subway systems is how to minimise the accumulation of inhalable particles generated by the moving trains impacts of (i) tunnel and rail track maintenance work activities; (ii) applying different ventilation on protocols in tunnels, platforms and trains; (iii) station designs and outdoor air infiltration; and (iv) contaminants released by the wear of train operational materials. These key points will be brought together in an overview of measures most likely to achieve notable improvement in subway air quality, along with a consideration of the benefits and drawbacks for each measure.
|Particles Exposure in Transport Microenvironments|
Prashant Kumar, University of Surrey, UK
Dr Prashant Kumar is a Professor (Full) and Chair in Air Quality & Health, and Founder Director of Global Centre for Clean Air Research (GCARE), at the University of Surrey, UK. His ground-breaking research works build an understanding of the formation and emission of particles, both from vehicle exhausts and also from construction and demolition. He investigates their contribution to pollution, especially in megacity contexts, and is developing approaches to low-cost sensing as well as contributing to guidelines for policymakers to curtail pollution exposure at hotspots, with associated health benefits. A prolific author with over 125 articles in top-ranked journals, his research has attracted funding from numerous national and international sources, developed a network of collaborators across four continents and serving editorial boards of nearly a dozen international journals.
|Large-scale studies using low cost particle monitors to estimate exposure|
Andrea Ferro, Clarkson University, USA
PM concentrations are typically measured by scientific-grade instruments located at fixed air quality stations for regulatory and research purposes. Studies have indicated that better spatially and temporally resolved PM measurements improves the associations between PM exposure and disease; however, the expense, size, and power and labor needs of the scientific-grade instruments limits the ability to provide these data. Recently, many new, low-cost sensors have been developed that could provide additional information to assess aerosol exposure. This talk will include a characterization of several low-cost PM monitors on the market today as well as findings from the deployment of more than 50 low-cost PM monitors in Rochester, NY over several seasons. The PM sensors were located indoors and outdoors at 25 residences for two consecutive winters and outdoors at 50 residences for one summer. For each winter and summer monitoring period, all monitors were collocated together for several days and at least one monitor was collocated for the season with a Thermo Scientific (Waltham, MA) 1405-DF tapered element oscillating microbalance (TEOM™). While the low-cost sensors lack good accuracy, they are reasonably precise. Thus, by combining a network of low-cost monitors with one or more scientific-grade instruments, we can achieve more highly resolved exposure assessment for individuals across a large geographical region or building complex.
|Air quality at schools |
Luca Stabile, University of Cassino and Southern Lazio, Italy
Schools represent a critical microenvironment in terms of indoor air quality standards since children spend a lot of time therein. Indeed, schools are often placed near highly-trafficked urban roads leading to high exposure to particles and other pollutants penetrating outdoor-to-indoor. Nonetheless, the indoor air quality is most of the time defined in terms of indoor CO2 concentration which cannot be considered a proxy for indoor particle concentration levels. The talk will summarize the results of the studies performed at the University of Cassino and Southern Lazio on children exposure in school microenvironments.
|From external exposure to an internal dose: modelling and extrapolation across species including humans|
Flemming Cassee, National Institute for Public Health and the Environment, The Netherlands
Risk assessment will be more and more based on the knowledge of the effective biological dose rather than the external concentration. Although we still need the later, dosimetry models will have to be applied to calculate the dose. This applies to both in vitro studies using cell cultures as well as exposure of humans and experimental animals. Such an approach would also facilitate the appreciation of in vitro toxicity tests. For nanomaterials it will also be important to understand the fraction of particles that will be translocated and removed from the site of deposition after inhalation.
|Nanoparticles in the atmosphere: what we know and which perspectives from toxicological studies|
Maurizio Gualtieri, ENEA Bologna, Italy
In the last years huge effort has been devoted in understanding the potential health impacts of nanometric aerosols. In vivo and in vitro toxicological studies provided fundamental data for the risk assessment of nanomaterials, identifying relevant biological pathways and responses activated by cells and tissue exposed to these novel materials. Nonetheless relevant questions rise when the doses of exposure in laboratory models are compared to environmental concentration experienced by population. In the last years novel experimental approaches allowed the exposure of biological models to environmental concentrations of nanoparticles. This possibility will permit the understanding of the effects expected under repeated exposure at very low doses and possibly define a unique mode of action of nano‐aerosols.
|Advances in Occupational Bioaerosol Exposure Science: solving larger puzzles |
Caroline Duchaine, Université Laval, Canada
Research on occupational bioaerosols is in its most prolific days, thanks to the availability of numerous promising technologies, including next generation sequencing, molecular biology, imaging and cytometry that allow faster and deeper characterization of workers exposure. The low number of recommended exposure limit values makes interpretation of exposure data challenging. Consequently, more in depth occupational exposure assessment are performed and interpretation of retrieved data is sometimes impossible. Following characterization of bioaerosols content using multiple approaches, it remains a challenge to understand the role of each of the various components of bioaerosols and synergistic effects of multiple exposures in the development of occupational diseases. Total endotoxins and glucans pyrogenic potential have been performed for many years and, nowadays, total inflammatory potential of bioaerosol samples can be assessed using cell models or whole blood assays. This presentation will review the options to better understand the roles of complex mixtures and evaluate if threshold exposure limits can be determined
Bioaerosols and their predictors in school environment
Heidi Salonen, Aalto University, Finland
In school environment, occupants are exposed to millions of bioaerosols, including e.g. fungi, bacteria and endotoxins, which can have beneficial and detrimental effects on human health. In our previous research and review studies, we have identified the amount of exposure to fungal bioaerosols and endotoxins, as well as their predictors in school environments in different climatic areas. We conducted field research in Finland and Australia, and in our literature review, we considered peer-reviewed manuscripts located using Google and PubMed, with search terms based on individual words and combinations. We also followed references from relevant articles. Analyses of the fungal data showed wide variation in the mean concentrations in outdoor and indoor school environments (range: 101-103 cfu/m3). These concentrations were significantly higher for both outdoors and indoors in the moderate climatic area compared to the continental, showing that the climatic condition was a determinant for the concentrations of airborne viable fungi. The most common fungal species both in the moderate and continental area were Cladosporium spp. and Penicillium spp. According to our study, the main factors influencing the concentration of viable fungi in the school buildings are eventual moisture damage in building structures, the season (temperature and humidity conditions), the type and rate of ventilation, the number and the activities of the occupants as well as daily variations. Analysis of the endotoxin data showed that, in school environments, the mean endotoxin loads in settled floor dust varied between, 2180 and 48,000 EU/m2, and correspondingly, the mean endotoxin concentrations in indoor air varied between 0.07 and 9.30 EU/m3. There is strong scientific evidence indicating that the age of the houses, the cleaning level, farm or rural living conditions, the presence of carpets, the number of occupants, the presence of dogs or cats indoors, and the relative humidity affect endotoxin loads in settled floor dust. The presence of dogs was extremely strongly associated with endotoxin concentrations in indoor air. However, concerning the effect of several environmental factors on bioaerosol levels, the literature findings are inconsistent and additional studies of different local factors contributing to human microbial exposure in school buildings—as well as other type of buildings and different indoor environments—are needed. In addition, our study recommends that further efforts should be made to create a standardized, uniform sampling methodology for different bioaerosols and to investigate the impact of different local factors in different climate regions.
|Friday, 20th April 2018|
|Health effects of indoor air pollutants from outdoor sources|
Francesco Forastiere, Etiological and Occupational Epidemiology, Department of Epidemiology Lazio Region, Italy
The health effects of outdoor air pollutants have been well studied and the worldwide health impact has been estimated. Less is known about the fractions of the outdoor pollutants that penetrate indoor and the possible health consequences. We will review the existing literature and the effectiveness of protective measures.
|Will future buildings, cars and energy production solve our air pollution problem?|
Otto Hänninen, National Institute for Health and Welfare, Finland
Megatrends and technologies of the 21st century promise us self-driving electric cars that have full protection of passengers also against road dust by using hepa filtering. Energy sector is going through a transition from fossil era to sun, wind, wave and fusion, promising to stop emissions of primary particles and precursor gases of secondary aerosols. For three decades aerosol scientists have used as an argument for the harmfulness of ultrafine particles the respiratory tract deposition curves that show highest probability of uptake at 10-50 nm size range. However, seldom it is accounted for how the infiltration of the aerosols from outdoor air into indoor spaces in buildings - or vehicles, to that matter - affects respiratory tract uptake efficiency. The presentation combines results from physically based aerosol size dependent infiltration model with the well-known respiratory tract deposition efficiency to show a somewhat unexpected result on the presumably "most toxic particle sizes." Nevertheless, the future building stock, becoming ever more energy efficient, insulates us better and better from outdoor air pollution meanwhile simultaneously optimizing energy needs and related emissions. Only our ever increasing space needs counter-balance this favourable development.
|Numerical modelling of ultrafine particles distribution: available approaches, criticalities and future developments|
Fausto Arpino, University of Cassino and Southern Lazio, Italy
Numerical modelling based on modern Computational Fluid Dynamic (CFD) technique represents nowadays a powerful tool to analyse velocity e pressure distribution in a large number of engineering applications. Numerical investigations are recently been applied to the description of ultrafine particles distribution from large scale (domains of several kilometres) to urban and indoor scales. The reliability of produced results significantly depends on the employed turbulence modelling approach and on the ability to accurately reproduce boundary conditions. The validation process is then crucial together to a proper uncertainty analysis of performed measurements.
|Aerosol dose deposited in the human respiratory system in indoor microenvironments |
Pasquale Avino, University of Molise, Italy
Exposure to airborne particles may lead to severe health effects. Nonetheless, in order to quantify the possible health effects due to such exposure, a dose-response relationship should be carried out instead of misleading exposure-response relationships. To this end, in the present research, an estimate of the particle dose received by exposed people in indoor environments was evaluated.