Publicação

Particulate matter generated in residential and commercial spaces: chemical signatures and mutagenic and cytotoxic effects

Detalhes bibliográficos
Resumo:	Indoor air quality (IAQ) is a critical factor influencing human health and well-being, given that people spend a significant portion of their time in enclosed environments such as homes, workplaces, and educational institutions. In fact, IAQ issues are equally or even more severe than outdoor pollution, accounting for over 4 million fatalities annually. Indoor pollutants can originate from various sources, including cooking, heating, cleaning products, building materials, and everyday human activities, as well as infiltration of outdoor air. Inadequate ventilation can exacerbate pollutant accumulation, leading to respiratory problems, allergies, and other health issues, particularly among vulnerable populations such as children, the elderly, and individuals with preexisting health conditions. Although there is extensive research on the emissions and composition of particles from various indoor sources, the toxicological effects of these particles remain poorly understood. This thesis aims to obtain the chemical and toxicological profiles of PM10 from different indoor sources, with a primary focus on the everyday life of individuals. The human alveolar epithelial (A549) cell model was selected to carry out the toxicological evaluation due to the significance of the respiratory system as a primary target of PM exposure. The chemical composition of particulate matter lower than 10 μm (PM10) samples was analysed for water-soluble inorganic ions, organic and elemental carbon (OC and EC), and detailed organic speciation. A series of in vitro tests was employed to evaluate the cytotoxic and mutagenic effects of the PM10 and associated polyaromatic compounds (PAHs) samples, respectively. In Chapter II, the toxicological responses of PM10 released from cooking and ironing activities under different conditions are investigated. The findings showed that PM10 organic extracts reduced the metabolic activity of A549 cells, and increased ROS levels in cells treated with PM10 from steam ironing, in low ventilation conditions, but did not affect the lactate dehydrogenase (LDH) release. Cell cycle dynamics were only affected by exposure to PM10 from frying horse mackerel and grilling boneless pork strips. No mutagenic effects were observed for all the PM10-bound PAHs samples using the Salmonella typhimurium strains TA100 and TA98. In chapter III, the cytotoxic and oxidative stress effects of PM10 were assessed, as well as the mutagenic potential of PM10-bound PAHs emitted during charcoal barbecue grilling. The outcomes revealed a significant decrease in cell viability in all tested samples, and increased reactive oxygen species (ROS) levels in cells treated with PM10 from starting a charcoal fire and from grilling boneless thin pork chops and pork belly. No alterations in cell cycle dynamics, LDH or mutagenic effects were observed. Chapter IV investigates the in vitro toxicity and composition of PM10-bound organics in indoor and outdoor air during coal combustion, as well as in the absence of the combustion source. Higher PAH concentrations were detected indoors than outdoors during coal burning, with high-molecular-weight PAHs, particularly indeno[1,2,3-cd]pyrene, dominating indoor PM10. Several compounds, including levoglucosan, phthalimide, oxidized Irgafos 168, phenolic compounds, dicarboxylic acids, and fatty acids were prevalent indoors when the emission source was active but scarce or absent outdoors or in the background indoor air. In vitro assays indicated that indoor PM10 from coal combustion induced cytotoxicity, oxidative stress, and cell cycle alterations, as well as an increase in necrotic cells. Correlation analysis linked PM-bound organics to adverse cellular effects. In chapter V, the chemical composition and toxicological effects of PM10 in a charcoal barbecue restaurant are discussed. The results show that PM10 concentrations indoors consistently exceeded outdoor levels on working days, with carbonaceous matter accounting for up to half of the PM10 mass. Potassium, sulphate, nitrite, and chloride were the dominant water-soluble ions indoors, while saccharides and cholesterol were among the most abundant organic compounds.Higher values for the oxidative potential by the dithiothreitol assay (OPoTr) were found indoors. A dosedependent decrease in cell viability for ali samples and increased ROS production were verified indoors, with positive correlations between ROS leveis and indoor phenolic compounds and carboxytic acids, as well as between outdoor steroid alcohols and ROS leveis. In chapter VI, the biological effects of PMio collected indoors and outdoors of a beauty salon are studied, as well as the mutagenic potential of PMio-bound PAHs. A dose-dependent decrease in cel! viability and an increase in ROS leveis was observed, as well as an arrest in the G1 phase of cell cycle. The biological responses were correlated with the concentrations of various compounds, including OC and some acids. No mutagenic effects were observed for ali PAH samples tested using the Salmonella typhimurium strain TA98. Finally, in chapterVII, the mutagenicity and the potential toxicotogical effects of PM 10 are evaluated in a university cafeteria, during occupancy and non-occupancy periods, as well as outdoors. The findings revealed a significant decrease in cell viability, particularly with PM 10 extracts collected indoors during occupancy, Elevated ROS leveis and cell cycle arrest in the GO/G1 phase were observed for these indoor samples. Significant correlations were identified between the concentrations of specifíc organic compounds and the observed biological responses. None of the PAH extracts tested showed mutagenic effects. Overall, this research highlights the potential health risks of indoor PMio exposure, emphasising the need for improved air quality management in enclosed environments.
Autores principais:	Figueiredo, Daniela Filipa Rodrigues
Assunto:	Indoor particulate matter Chemical composition A549 cells Cytotoxicity Oxidative potential Oxidative stress Cell cycle Apoptosis Mutagenicity
Ano:	2025
País:	Portugal
Tipo de documento:	tese de doutoramento
Tipo de acesso:	acesso embargado
Instituição associada:	Universidade de Aveiro
Idioma:	inglês
Origem:	RIA - Repositório Institucional da Universidade de Aveiro

Descrição
Resumo:	Indoor air quality (IAQ) is a critical factor influencing human health and well-being, given that people spend a significant portion of their time in enclosed environments such as homes, workplaces, and educational institutions. In fact, IAQ issues are equally or even more severe than outdoor pollution, accounting for over 4 million fatalities annually. Indoor pollutants can originate from various sources, including cooking, heating, cleaning products, building materials, and everyday human activities, as well as infiltration of outdoor air. Inadequate ventilation can exacerbate pollutant accumulation, leading to respiratory problems, allergies, and other health issues, particularly among vulnerable populations such as children, the elderly, and individuals with preexisting health conditions. Although there is extensive research on the emissions and composition of particles from various indoor sources, the toxicological effects of these particles remain poorly understood. This thesis aims to obtain the chemical and toxicological profiles of PM10 from different indoor sources, with a primary focus on the everyday life of individuals. The human alveolar epithelial (A549) cell model was selected to carry out the toxicological evaluation due to the significance of the respiratory system as a primary target of PM exposure. The chemical composition of particulate matter lower than 10 μm (PM10) samples was analysed for water-soluble inorganic ions, organic and elemental carbon (OC and EC), and detailed organic speciation. A series of in vitro tests was employed to evaluate the cytotoxic and mutagenic effects of the PM10 and associated polyaromatic compounds (PAHs) samples, respectively. In Chapter II, the toxicological responses of PM10 released from cooking and ironing activities under different conditions are investigated. The findings showed that PM10 organic extracts reduced the metabolic activity of A549 cells, and increased ROS levels in cells treated with PM10 from steam ironing, in low ventilation conditions, but did not affect the lactate dehydrogenase (LDH) release. Cell cycle dynamics were only affected by exposure to PM10 from frying horse mackerel and grilling boneless pork strips. No mutagenic effects were observed for all the PM10-bound PAHs samples using the Salmonella typhimurium strains TA100 and TA98. In chapter III, the cytotoxic and oxidative stress effects of PM10 were assessed, as well as the mutagenic potential of PM10-bound PAHs emitted during charcoal barbecue grilling. The outcomes revealed a significant decrease in cell viability in all tested samples, and increased reactive oxygen species (ROS) levels in cells treated with PM10 from starting a charcoal fire and from grilling boneless thin pork chops and pork belly. No alterations in cell cycle dynamics, LDH or mutagenic effects were observed. Chapter IV investigates the in vitro toxicity and composition of PM10-bound organics in indoor and outdoor air during coal combustion, as well as in the absence of the combustion source. Higher PAH concentrations were detected indoors than outdoors during coal burning, with high-molecular-weight PAHs, particularly indeno[1,2,3-cd]pyrene, dominating indoor PM10. Several compounds, including levoglucosan, phthalimide, oxidized Irgafos 168, phenolic compounds, dicarboxylic acids, and fatty acids were prevalent indoors when the emission source was active but scarce or absent outdoors or in the background indoor air. In vitro assays indicated that indoor PM10 from coal combustion induced cytotoxicity, oxidative stress, and cell cycle alterations, as well as an increase in necrotic cells. Correlation analysis linked PM-bound organics to adverse cellular effects. In chapter V, the chemical composition and toxicological effects of PM10 in a charcoal barbecue restaurant are discussed. The results show that PM10 concentrations indoors consistently exceeded outdoor levels on working days, with carbonaceous matter accounting for up to half of the PM10 mass. Potassium, sulphate, nitrite, and chloride were the dominant water-soluble ions indoors, while saccharides and cholesterol were among the most abundant organic compounds.Higher values for the oxidative potential by the dithiothreitol assay (OPoTr) were found indoors. A dosedependent decrease in cell viability for ali samples and increased ROS production were verified indoors, with positive correlations between ROS leveis and indoor phenolic compounds and carboxytic acids, as well as between outdoor steroid alcohols and ROS leveis. In chapter VI, the biological effects of PMio collected indoors and outdoors of a beauty salon are studied, as well as the mutagenic potential of PMio-bound PAHs. A dose-dependent decrease in cel! viability and an increase in ROS leveis was observed, as well as an arrest in the G1 phase of cell cycle. The biological responses were correlated with the concentrations of various compounds, including OC and some acids. No mutagenic effects were observed for ali PAH samples tested using the Salmonella typhimurium strain TA98. Finally, in chapterVII, the mutagenicity and the potential toxicotogical effects of PM 10 are evaluated in a university cafeteria, during occupancy and non-occupancy periods, as well as outdoors. The findings revealed a significant decrease in cell viability, particularly with PM 10 extracts collected indoors during occupancy, Elevated ROS leveis and cell cycle arrest in the GO/G1 phase were observed for these indoor samples. Significant correlations were identified between the concentrations of specifíc organic compounds and the observed biological responses. None of the PAH extracts tested showed mutagenic effects. Overall, this research highlights the potential health risks of indoor PMio exposure, emphasising the need for improved air quality management in enclosed environments.