Introdução - Alguns tipos de fungos, como o mofo, são de fundamental importância médica, principalmente por produzirem toxinas nocivas à saúde dos humanos. São frequentemente encontrados no interior dos domicílios quando há condição favorável, como umidade e temperatura adequada. Vários estudos relataram associação entre mofo e doenças alérgicas ou respiratórias em crianças. Objetivos - Descrever as características dos domicílios dos recém-nascidos incluídos em um estudo de coorte na cidade de São Paulo e identificar as possíveis associações com o desenvolvimento de mofo visível nas superfícies (paredes, piso e teto). Métodos - Este trabalho faz parte de uma coorte de recém-nascidos com início em 2003 e término em 2007, denominada PROJETO CHIADO. Participaram do estudo 378 domicílios. Entrevistadores fizeram visitas nestas residências para coletar dados referentes às características dos domicílios (tipo de cobertura, tipo de forro, idade da construção) e condições intra-domiciliares (ventilação, aglomeração, incidência solar, temperatura, presença de umidade, presença de mofo). Foram realizadas análises descritivas e análises bivariável e multivariável (regressão logística) para identificar possíveis associações entre as características dos domicílios e a presença de mofo. Resultados Foi encontrado mofo visível na maioria dos domicílios visitados (66 por cento), sendo 28 por cento no quarto da criança e 38 por cento em outros cômodos. Foi relatada umidade em aproximadamente metade dos domicílios (47 por cento) e ventilação regular, ruim ou péssima em 42 por cento. Foram identificadas associações positivas entre a presença de mofo no quarto da criança e ventilação ruim ou péssima (OR=2,14; IC95 por cento:1,05-4,38), falta de incidência solar no verão (OR=3,84; IC95 por cento:1,59-9,28) e aglomeração de quatro ou mais pessoas no quarto da criança (OR=2,09; IC95 por cento:1,24-3,50). Por outro lado, os tipos construtivos apresentaram associação inversa com o mofo (OR=0,41; IC95 por cento: 0,17-1,01) para cobertura com telha de cerâmica e forro de madeira ou cobertura com fibrocimento e forro de concreto e OR=0,40; IC95 por cento: 0,18-0,90 para cobertura com telha de cerâmica e forro de concreto. Conclusão Ventilação precária, falta de incidência solar no domicílio durante o verão e aglomeração de pessoas no domicílio propiciam o desenvolvimento de mofo enquanto que os tipos construtivos com coberturas feitas com materiais de maior densidade protegem os domicílios contra o desenvolvimento de mofo. A partir do conhecimento das características dos domicílios, é possível realizar intervenções para evitar o crescimento do mofo / Introduction Some kind of fungi, such as mold, has fundamental medical importance, especially by producing toxins harmful to human health. They are often found inside the homes when there are favorable conditions, such as appropriated humidity and temperature. Several studies have reported associations between mold and respiratory and allergic diseases in children. Objectives To describe the household characteristics of the newborns included in a cohort study in the city of São Paulo and to identify possible associations with the visible mold development on the surfaces (walls, floors and ceiling). Methods This study is part of a newborns cohort study that started in 2003 and finished in 2007, called WHEEZING PROJECT. 378 households participated in the study. Interviewers visited the homes to collect data from households characteristics (type of roof, type of ceiling, building age) and indoor conditions (ventilation, crowding, solar incidence, temperature, presence of moisture, presence of mold). Descriptive analyses and bivariate and multivariate analyses (logistic regression) were performed to identify associations between households characteristics and the presence of mold. Results Visible mold was found in most households visited (66 per cent), 28 per cent in the child´s room and 38 per cent in the other rooms. Moisture was reported in 47 per cent of the houses, and regular, bad or very bad ventilation in 42 per cent. Positive associations were found between the presence of mold in the homes and bad or very bad ventilation (OR=2,14; 95 per centCI: 1,05-4,38), no solar incidence in the summer (OR=3,84; 95 per centCI: 1,59-9,28) and crowding of at least four people in the child´s room (OR=2,09, 95 per centCI: 1,24-3,50). On the other hand, the type of construction showed inverse association with the mold (OR=0,41; 95 per centCI: 0,17-1,01) to ceramic tile roof and wood ceiling or cement-fibre roof and concrete ceiling and OR=0,40; CI IC95 per cent: 0,18-0,90 to ceramic tile and concrete ceiling. Conclusion Poor ventilation, no solar incidence in the home during the summer and crowding in the child´s room facilitate the development of mold, while the type of construction with high density materials protects the homes against the mold development. From the knowledge of the households characteristics, it is possible to perform interventions to prevent mold growth

Introdução - Alguns tipos de fungos, como o mofo, são de fundamental importância médica, principalmente por produzirem toxinas nocivas à saúde dos humanos. São frequentemente encontrados no interior dos domicílios quando há condição favorável, como umidade e temperatura adequada. Vários estudos relataram associação entre mofo e doenças alérgicas ou respiratórias em crianças. Objetivos - Descrever as características dos domicílios dos recém-nascidos incluídos em um estudo de coorte na cidade de São Paulo e identificar as possíveis associações com o desenvolvimento de mofo visível nas superfícies (paredes, piso e teto). Métodos - Este trabalho faz parte de uma coorte de recém-nascidos com início em 2003 e término em 2007, denominada PROJETO CHIADO. Participaram do estudo 378 domicílios. Entrevistadores fizeram visitas nestas residências para coletar dados referentes às características dos domicílios (tipo de cobertura, tipo de forro, idade da construção) e condições intra-domiciliares (ventilação, aglomeração, incidência solar, temperatura, presença de umidade, presença de mofo). Foram realizadas análises descritivas e análises bivariável e multivariável (regressão logística) para identificar possíveis associações entre as características dos domicílios e a presença de mofo. Resultados Foi encontrado mofo visível na maioria dos domicílios visitados (66 por cento), sendo 28 por cento no quarto da criança e 38 por cento em outros cômodos. Foi relatada umidade em aproximadamente metade dos domicílios (47 por cento) e ventilação regular, ruim ou péssima em 42 por cento. Foram identificadas associações positivas entre a presença de mofo no quarto da criança e ventilação ruim ou péssima (OR=2,14; IC95 por cento:1,05-4,38), falta de incidência solar no verão (OR=3,84; IC95 por cento:1,59-9,28) e aglomeração de quatro ou mais pessoas no quarto da criança (OR=2,09; IC95 por cento:1,24-3,50). Por outro lado, os tipos construtivos apresentaram associação inversa com o mofo (OR=0,41; IC95 por cento: 0,17-1,01) para cobertura com telha de cerâmica e forro de madeira ou cobertura com fibrocimento e forro de concreto e OR=0,40; IC95 por cento: 0,18-0,90 para cobertura com telha de cerâmica e forro de concreto. Conclusão Ventilação precária, falta de incidência solar no domicílio durante o verão e aglomeração de pessoas no domicílio propiciam o desenvolvimento de mofo enquanto que os tipos construtivos com coberturas feitas com materiais de maior densidade protegem os domicílios contra o desenvolvimento de mofo. A partir do conhecimento das características dos domicílios, é possível realizar intervenções para evitar o crescimento do mofo / Introduction Some kind of fungi, such as mold, has fundamental medical importance, especially by producing toxins harmful to human health. They are often found inside the homes when there are favorable conditions, such as appropriated humidity and temperature. Several studies have reported associations between mold and respiratory and allergic diseases in children. Objectives To describe the household characteristics of the newborns included in a cohort study in the city of São Paulo and to identify possible associations with the visible mold development on the surfaces (walls, floors and ceiling). Methods This study is part of a newborns cohort study that started in 2003 and finished in 2007, called WHEEZING PROJECT. 378 households participated in the study. Interviewers visited the homes to collect data from households characteristics (type of roof, type of ceiling, building age) and indoor conditions (ventilation, crowding, solar incidence, temperature, presence of moisture, presence of mold). Descriptive analyses and bivariate and multivariate analyses (logistic regression) were performed to identify associations between households characteristics and the presence of mold. Results Visible mold was found in most households visited (66 per cent), 28 per cent in the child´s room and 38 per cent in the other rooms. Moisture was reported in 47 per cent of the houses, and regular, bad or very bad ventilation in 42 per cent. Positive associations were found between the presence of mold in the homes and bad or very bad ventilation (OR=2,14; 95 per centCI: 1,05-4,38), no solar incidence in the summer (OR=3,84; 95 per centCI: 1,59-9,28) and crowding of at least four people in the child´s room (OR=2,09, 95 per centCI: 1,24-3,50). On the other hand, the type of construction showed inverse association with the mold (OR=0,41; 95 per centCI: 0,17-1,01) to ceramic tile roof and wood ceiling or cement-fibre roof and concrete ceiling and OR=0,40; CI IC95 per cent: 0,18-0,90 to ceramic tile and concrete ceiling. Conclusion Poor ventilation, no solar incidence in the home during the summer and crowding in the child´s room facilitate the development of mold, while the type of construction with high density materials protects the homes against the mold development. From the knowledge of the households characteristics, it is possible to perform interventions to prevent mold growth

The understanding of human exposure to indoor particles of all sizes is important to enable exposure control and reduction, but especially for smaller particles since the smaller particles have a higher probability of penetration into the deeper parts of the respiratory tract and also contain higher levels of trace elements and toxins. Due to the limited understanding of the relationship between particle size and the health effects they cause, as well as instrument limitations, the available information on submicrometer (d < 1.0 µm) particles indoors, both in terms of mass and number concentrations, is still relatively limited. This PhD project was conducted as part of the South-East Queensland Air Quality program and Queensland Housing Study aimed at providing a better understanding of ambient particle concentrations within the indoor environment with a focus on exposure assessment and control. This PhD project was designed to investigate comprehensively the sources and sinks of indoor aerosol particles and the relationship between indoor and outdoor aerosol particles, particle and gaseous pollutant, as well as the association between indoor air pollutants and house characteristics by using, analysing and interpreting existing experimental data which were collected before this project commenced, as well as data from additional experiments which were designed and conducted for the purpose of this project. The focus of this research was on submicrometer particles with a diameter between 0.007 - 0.808 µm. The main outcome of this project may be summarised as following: * A comprehensive review of particle concentration levels and size distributions characteristics in the residential and non-industrial workplace environments was conducted. This review included only those studies in which more general trends were investigated, or could be concluded based on information provided in the papers. This review included four parts: 1) outdoor particles and their effect on indoor environments; 2) the relationship between indoor and outdoor concentration levels in the absence of indoor sources for naturally ventilated buildings; 3) indoor sources of particles: contribution to indoor concentration levels and the effect on I/O ratios for naturally ventilated buildings; and 4) indoor/outdoor relationship in mechanically ventilated buildings. * The relationship between indoor and outdoor airborne particles was investigated for sixteen residential houses in Brisbane, Australia, in the absence of operating indoor sources. Comparison of the ratios of indoor to outdoor particle concentrations revealed that while temporary values of the ratio vary in a broad range from 0.2 to 2.5 for both lower and higher ventilation conditions, average values of the ratios were very close to one regardless of ventilation conditions and of particle size range. The ratios were in the range from 0.78 to 1.07 for submicrometer particles, from 0.95 to 1.0 for supermicrometer particles and from 1.01 to 1.08 for PM2.5 fraction. Comparison of the time series of indoor to outdoor particle concentrations showed a clear positive relationship existing for many houses under normal ventilation conditions (estimated to be about and above 2 h-1), but not under minimum ventilation conditions (estimated to be about and below 1 h-1). These results suggest that for normal ventilation conditions and in the absence of operating indoor sources, outdoor particle concentrations could be used to predict instantaneous indoor particle concentrations but not for minium ventilation, unless air exchange rate is known, thus allowing for estimation of the "delay constant". * Diurnal variation of indoor submicrometer particle number and particle mass (approximation of PM2.5) concentrations was investigated in fifteen of the houses. The results show that there were clear diurnal variations in both particle number and approximation of PM2.5 concentrations, for all the investigated houses. The pattern of diurnal variations varied from house to house, however, there was always a close relationship between the concentration and human indoor activities. The average number and mass concentrations during indoor activities were (18.2±3.9)×10³ particles cm-³ and (15.5±7.9) µg m-³ respectively, and under non-activity conditions, (12.4±2.7)x10³ particles cm-³ (11.1±2.6) µg m-³, respectively. In general, there was a poor correlation between mass and number concentrations and the correlation coefficients were highly variable from day to day and from house to house. This implies that conclusions cannot be drawn about either one of the number or mass concentration characteristics of indoor particles, based on measurement of the other. The study also showed that it is unlikely that particle concentrations indoors could be represented by measurements conducted at a fixed monitoring station due to the large impact of indoor and local sources. * Emission characteristics of indoor particle sources in fourteen residential houses were quantified. In addition, characterizations of particles resulting from cooking conducted in an identical way in all the houses were measured. All the events of elevated particle concentrations were linked to indoor activities using house occupants diary entries, and catalogued into 21 different types of indoor activities. This enabled quantification of the effect of indoor sources on indoor particle concentrations as well as quantification of emission rates from the sources. For example, the study found that frying, grilling, stove use, toasting, cooking pizza, smoking, candle vaporizing eucalyptus oil and fan heater use, could elevate the indoor submicrometer particle number concentration levels by more than 5 times, while PM2.5 concentrations could be up to 3, 30 and 90 times higher than the background levels during smoking, frying and grilling, respectively. * Indoor particle deposition rates of size classified particles in the size range from 0.015 to 6 µm were quantified. Particle size distribution resulting from cooking, repeated under two different ventilation conditions in 14 houses, as well as changes to particle size distribution as a function of time, were measured using a scanning mobility particle sizer (SMPS), an aerodynamic particle sizer (APS), and a DustTrak. Deposition rates were determined by regression fitting of the measured size-resolved particle number and PM2.5 concentration decay curves, and accounting for air exchange rate. The measured deposition rates were shown to be particle size dependent and they varied from house to house. The lowest deposition rates were found for particles in the size range from 0.2 to 0.3 µm for both minimum (air exchange rate: 0.61±0.45 h-1) and normal (air exchange rate: 3.00±1.23 h-1) ventilation conditions. The results of statistical analysis indicated that ventilation condition (measured in terms of air exchange rate) was an important factor affecting deposition rates for particles in the size range from 0.08 to 1.0 µm, but not for particles smaller than 0.08 µm or larger than 1.0 µm. Particle coagulation was assessed to be negligible compared to the two other processes of removal: ventilation and deposition. This study of particle deposition rates, the largest conducted so far in terms of the number of residential houses investigated, demonstrated trends in deposition rates comparable with studies previously reported, usually for significantly smaller samples of houses (often only one). However, the results compare better with studies which, similarly to this study, investigated cooking as a source of particles (particle sources investigated in other studies included general activity, cleaning, artificial particles, etc). * Residential indoor and outdoor 48 h average levels of nitrogen dioxide (NO2), 48h indoor submicrometer particle number concentration and the approximation of PM2.5 concentrations were measured simultaneously for fourteen houses. Statistical analyses of the correlation between indoor and outdoor pollutants (NO2 and particles) and the association between house characteristics and indoor pollutants were conducted. The average indoor and outdoor NO2 levels were 13.8 ± 6.3 ppb and 16.7 ± 4.2 ppb, respectively. The indoor/outdoor NO2 concentration ratio ranged from 0.4 to 2.3, with a median value of 0.82. Despite statistically significant correlations between outdoor and fixed site NO2 monitoring station concentrations (p = 0.014, p = 0.008), there was no significant correlation between either indoor and outdoor NO2 concentrations (p = 0.428), or between indoor and fixed site NO2 monitoring station concentrations (p = 0.252, p = 0.465,). However, there was a significant correlation between indoor NO2 concentration and indoor submicrometer aerosol particle number concentrations (p = 0.001), as well as between indoor PM2.5 and outdoor NO2 (p = 0.004). These results imply that the outdoor or fixed site monitoring concentration alone is a poor predictor of indoor NO2 concentration. * Analysis of variance indicated that there was no significant association between indoor PM2.5 and any of the house characteristics investigated (p > 0.05). However, associations between indoor submicrometer particle number concentration and some house characteristics (stove type, water heater type, number of cars and condition of paintwork) were significant at the 5% level. Associations between indoor NO2 and some house characteristics (house age, stove type, heating system, water heater type and floor type) were also significant (p < 0.05). The results of these analyses thus strongly suggest that the gas stove, gas heating system and gas water heater system are main indoor sources of indoor submicrometer particle and NO2 concentrations in the studied residential houses. The significant contributions of this PhD project to the knowledge of indoor particle included: 1) improving an understanding of indoor particles behaviour in residential houses, especially for submicrometer particle; 2) improving an understanding of indoor particle source and indoor particle sink characteristics, as well as their effects on indoor particle concentration levels in residential houses; 3) improving an understanding of the relationship between indoor and outdoor particles, the relationship between particle mass and particle number, correlation between indoor NO2 and indoor particles, as well as association between indoor particle, NO2 and house characteristics.