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Abstract
The use of electronic cigarettes (e-cigarettes or "vaping") has seen an unprecedented increase worldwide. Vaping has been promoted as a beneficial smoking cessation tool and an alternative nicotine delivery device that contains no combustion by-products. However, nicotine is highly addictive, and the increased use of nicotine-containing e-cigarettes among teens and individuals who are not in need of smoking cessation may lead to overall greater nicotine dependence in the population. Furthermore, available research indicates that vaping solutions and their emissions may contain much more than just nicotine, including aerosolized flavorings, propylene glycol (PG), and other intentional and unintentional contaminants. These materials could present undefined potential health hazards to both e-cigarette users and bystanders, the full extent of which is not well understood at this time. Whereas e-cigarette usage and exposures may lower some or most of the risks associated with conventional cigarette use, the health effects of nicotine and aerosol exposures from e-cigarettes are not well understood. Research indicates that vaping aerosols are not benign, especially for nearby people in areas with limited ventilation and people with compromised health conditions. In addition, e-juice liquids have already been responsible for an increase in accidental poisonings in children. Because the magnitude of health and safety hazards that vaping may present to nonusers remains unclear, it is prudent to manage and control vaping in indoor locations where smoking is currently restricted. Based on a review of current scientific information, the American Industrial Hygiene Association (AIHA) recommends that e-cigarettes should be considered a source of aerosols, volatile organic compounds (VOCs), and particulates in the indoor environment that have not been thoroughly characterized or evaluated for health risk or safety.

The location estimation of a target for a long period was performed only by device based localisation technique which is difficult in applications where target especially human is non-cooperative. A target was detected by equipping a device using global positioning systems, radio frequency systems, ultrasonic frequency systems, etc. Device free localisation (DFL) is an upcoming technology in automated localisation in which target need not equip any device for identifying its position by the user. For achieving this objective, the wireless sensor network is a better choice due to its growing popularity. This paper describes the possible categorisation of recently developed DFL techniques using wireless sensor network. The scope of each category of techniques is analysed by comparing their potential benefits and drawbacks. Finally, future scope and research directions in this field are also summarised.

Dampness in indoor environments may cause various health problems. The specific causative agent(s) are unknown but may originate from degradation processes in damp materials, microbial growth, or a combination of these phenomena. The health impact of dampness in buildings is a politically, legally, and economically important question. Scientists at the U.S. EPA and Lawrence Berkeley National Laboratory have estimated that the symptoms of 4.6 of the total of 21.8 million asthmatics in the USA are caused by indoor dampness and mold to an annual cost of 3.5 billion dollars. Mycotoxins are secondary metabolites produced by molds which may be e. g. cytotoxic (e. g. macrocyclic trichothecenes produced by Stachybotrys chartarum), genotoxic (e. g. sterigmatocystin and aflatoxins produced mainly by Aspergillus spp. including A. versicolor and A. flavus), or immunosuppressive and neurotoxic (e. g. gliotoxin produced by Penicillium spp. and Aspergillus spp. e. g. A. fumigatus). Airborne mycotoxins have been demonstrated in water-damaged buildings using both ELISA and mass spectrometry. However, whether mycotoxins at the concentrations found in mold-damaged environments represent a health risk upon inhalation is not known. The mechanisms for mycotoxin uptake, metabolism, and interaction e. g. with other fungal constituents such as proteins and (1→3)-β-D-glucan (a fungal cell membrane constituent) are poorly understood. In this project analytical methods for the detection and determination of selected mycotoxins using GC-MS and HPLC-MS were developed. The methods were applied to 167 mold-contaminated building material samples, of which 67 % were mycotoxin positive. Thus, many molds not only posess the genetic capacity to produce mycotoxins but do it regularly in water damaged indoor environments. In addition, we demonstrated mycotoxins in dust settled in the breathing zone in indoor environments where severe mold-contamination was identified on building materials. We thereby confirm that mycotoxins on such materials can become airborne and thus inhalable. This project is an example of fruitful national and international inter-disciplinary collaboration between the building industry, companies specialized in remediation measures, and universities.

Covering the fundamentals of air-borne particles and settled dust in the indoor environment, this handy reference investigates: relevant definitions and terminology; characteristics; sources; sampling techniques and instrumentation; exposure assessment; monitoring methods. The result is a useful and comprehensive overview for chemists, physicists and biologists, postgraduate students, medical practitioners, occupational health professionals, building owners and managers, building, construction and air-conditioning engineers, architects, environmental lawyers, government and regulatory professi

Military facilities feature distinctive requirements with regards to building technical and structural design, material use and indoor environmental conditions (IEC), as these buildings serve specific purpose and the personnel occupying the premises may wear uniform or protective clothing (administrative staff, special forces, training personnel etc.), that can greatly affect their satisfaction level with thermal comfort and productivity. In order to acquire data on the actual indoor environment conditions and obtain a feedback from the occupying personnel on their satisfaction level with the IEC in an administrative military building situated in a special purpose military compound, a series of IAQ measurements (temperature, humidity, CO2 level) and a survey on indoor air quality and thermal comfort was conducted in different premises of the administrative office building. A total of 73 respondents occupying the building participated in the survey. The results of the conducted survey revealed that there is a high degree of dissatisfaction with the IEC in military buildings, that is attributed to inadequate ventilation and overtemperature. That matched the collected indoor environmental quality (IEQ) data, forming a direct relationship between the poor energy efficiency and low satisfaction rate with IEC. The study reiterates the need to address the poor current technical state of unclassified building stock, emphasizes the call for developing clear regulatory requirements for newly-constructed unclassified buildings and thorough feasibility assessment for renovation projects.

LIFE Index-Air project (LIFE15 ENV/PT/000674). FCT_UID/Multi/04349/2019. ; The exposure to particles and bioaerosols has been associated with the increase in health effects in children. The objective of this study was to assess the indoor exposure to bioburden in the indoor microenvironments more frequented by children. Air particulate matter (PM) and settled dust were sampled in 33 dwellings and four schools with a medium volume sampler and with a passive method using electrostatic dust collectors (EDC), respectively. Settled dust collected by EDC was analyzed by culture-based methods (including azole resistance profile) and using qPCR. Results showed that the PM2.5 and PM10 concentrations in classrooms (31.15 μg/m3 and 57.83 μg/m3, respectively) were higher than in homes (15.26 μg/m3 and 18.95 μg/m3, respectively) and highly exceeded the limit values established by the Portuguese legislation for indoor air quality. The fungal species most commonly found in bedrooms was Penicillium sp. (91.79%), whereas, in living rooms, it was Rhizopus sp. (37.95%). Aspergillus sections with toxigenic potential were found in bedrooms and living rooms and were able to grow on VOR. Although not correlated with PM, EDC provided information regarding the bioburden. Future studies, applying EDC coupled with PM assessment, should be implemented to allow for a long-term integrated sample of organic dust. ; info:eu-repo/semantics/publishedVersion

Apresentação em efectuada na "2nd Conference Environment and Public Health (EPH), Berlin-Potsdam, Germany, 2011" ; Development of building technologies is tightly connected in the network of energy saving demands of growing population, significant problems with waste and economy which tries to be self-sustainble, balancing between profit, social trends like fashion, need for higher living standard and rasing awareness of ireversible destroy of nature. In such social and economical environment building construction sector introduces new technologies and materials which brought large improvement in obeying all these demands but also produces a new complex indoor radiochemical environment. Elimination of waste such as a fly ash by its incorporation in concrete is significinat from the ecological viewpoint, but it may cause increased indoor emissions of ionizing radiation due to the fact that it may contain high levels of radioisotopes. Additionally to indoor radon which levels may be elevated due to regional soil characteristics, usage of zirconium and granit as fashionable elements of indoor finishing can also contribute to final increased exposure to ionizing radiation. Finishing indoor materials which contain nano particles, flame retardants, different organic compounds or ammonia combined with ionizing radiation may produce very complex health effects on occupants, especially on children and possible transplacental effects on fetal development. Introduction of occupancy/use permit which will include measurement of indoor radiochemical emissions will improve life standards and enable enforcement of politics in which occupants will have option to select residence with healty indoor environment. Building construction can be stimulated to apply for such permits via tax ...

Humans spend most of their time indoors, in residences and commercial buildings. In this thesis, I evaluate exposures to volatile (VOCs) and semivolatile organic compounds (SVOCs) in indoor environments. I use a combination of literature review and evaluation, mechanistic modeling, and skin-wipe collection and analysis to develop an understanding of the role of indoor air as an exposure medium for inhalation and passive dermal uptake of pollutants. This dissertation explores three related research topics on indoor environments and human exposures. In Chapter 2, I conduct a comprehensive review of reported measurements of pollutants found in commercial buildings. I used the literature review to estimate concentration ranges that can be compared to health-based exposure limits as basis for hazard assessment. I use the regulatory exposure limits set by government agencies to calculate hazard indices as the ratio of observed concentrations to regulatory standards. I also compare the odor and pungency thresholds of individual pollutants to observed concentrations to evaluate their potential to exceed odor thresholds. The hazard evaluation identifies the potential for health impacts at concentrations commonly found in commercial buildings. This analysis focuses exclusively on VOCs and SVOCs in commercial buildings and identified a limited set of pollutants that pose health concerns. I also characterize the selected pollutants in terms of the chemical properties that,affect partitioning to various indoor surfaces, and subsequently their fate and transport in indoor environments. Based on chemical properties and indoor fate, I grouped the pollutants into five groups. I use an hierarchical k-means analysis based on octanol-air partitioning coefficient, octanol-water partitioning coefficient, air-water partitioning coefficient, and molecular weight. The pollutants in each group are expected to behave similarly in indoor environments. In Chapter 3, I evaluate the role of buildings operation parameters such as ventilation and filtration in limiting exposures to pollutants originating from indoor and outdoor sources. I use a simple well-mixed-air model of an indoor space to study the impact of ventilation on concentrations of ozone, nitrogen dioxide, carbon monoxide, and radon. I employ a chemical-thermodynamics-(fugacity)-based mass balance model in conjunction with a particle mass balance to study the fate and transport of particulate matter, VOCs, and SVOCs. The fugacity mass balance model accounts for chemical partitioning among air, air-borne particles, and indoor surfaces. I ran the fugacity model with indoor and outdoor source of VOCs and SVOCs and indoor and outdoor sources of particulate matter. I evaluate the consequent inhalation exposures these sources with two outcome metrics, intake fraction (iF) for indoor sources and indoor/outdoor concentration ratio for outdoor sources. The exposure to particulate matter of indoor and outdoor origin was evaluated using the outcome metrics iF and the indoor proportion of outdoor particles (iPOP). The model evaluation shows that ventilation is most effective at controlling exposures to VOCs that have an indoor source. Filtration is seen to be effective at controlling exposures to particulate matter and SVOCs that partition preferentially onto particulate matter. In Chapter 4, I explore the role of indoor air in delivering SVOCs to human occupants through passive dermal uptake. I collected wipe samples from thirteen subjects who were randomly chosen. For each subject, I collected three sequential wipe samples from the forehead and one sample from the palm. I analyzed the samples for a suite of SVOCs and skin lipids (squalene and sapienic acid) in an analytical laboratory using gas chromatography and liquid chromatography. All forehead wipe samples contained SVOCs indicating that air to skin transfer of pollutants for passive dermal uptake could be a significant exposure pathway for SVOCs. Because skin lipid concentrations decrease with depth the quantitation of skin lipid concentrations from each wipe allowed me to estimate the depth of sampling by each skin wipe. This is the first study to quantitatively evaluate the depth of sampling by skin wipes. I use the experimental results together with a theoretical model to explore the potential role of skin as a passive sampler for short-term personal exposures, indoors. For this I develop a metric called the equivalent time of exposure (ETE) to study the usefulness of sequential skin wipe samples as a passive sampler. I used partitioning coefficients from air to skin surface, combined with a dynamic skin mass transport model, to study the theoretical transport of pollutant through the stratum corneum. I compare the modeled concentrations to measured concentrations, at comparable depths. The ETE is the amount of time to which the subject would have to be exposed to a constant air concentration to attain the observed skin-wipe concentration depth profile in the stratum corneum. Based on the ETE, I find that skin wipe samples could be indicative of exposures up to 6 hours prior to wipe sampling, depending on the diffusion coefficient of the pollutant. The overarching goal of this research is to evaluate the role of indoor air in mediating the transfer to human receptors of pollutants released indoors or brought indoors from outdoor sources. The indoor air mass controls the fate and transport of pollutants in indoor spaces, and the rate of delivery of pollutants for inhalation and dermal uptake. The research highlights the important role of air-to-surface and air-to-particle partitioning in facilitating or mitigating source-receptor relationships. The work illustrates future research opportunities for tracking the complex web of indoor/outdoor pathways that bring pollutants into the human environment and into the blood and other viable tissues of the human population.

The exposure to particles and bioaerosols has been associated with the increase in health effects in children. The objective of this study was to assess the indoor exposure to bioburden in the indoor microenvironments more frequented by children. Air particulate matter (PM) and settled dust were sampled in 33 dwellings and four schools with a medium volume sampler and with a passive method using electrostatic dust collectors (EDC), respectively. Settled dust collected by EDC was analyzed by culture-based methods (including azole resistance profile) and using qPCR. Results showed that the PM2.5 and PM10 concentrations in classrooms (31.15 μg/m3 and 57.83 μg/m3, respectively) were higher than in homes (15.26 μg/m3 and 18.95 μg/m3, respectively) and highly exceeded the limit values established by the Portuguese legislation for indoor air quality. The fungal species most commonly found in bedrooms was Penicillium sp. (91.79%), whereas, in living rooms, it was Rhizopus sp. (37.95%). Aspergillus sections with toxigenic potential were found in bedrooms and living rooms and were able to grow on VOR. Although not correlated with PM, EDC provided information regarding the bioburden. Future studies, applying EDC coupled with PM assessment, should be implemented to allow for a long-term integrated sample of organic dust. ; publishersversion ; published