Window Condensation Research Articles

Associations between home environmental factors and childhood eczema and related symptoms in different cities in China

Previous studies have shown significant associations between home environmental factors and childhood eczema. However, few studies have compared how associations differ in different regions. This study investigated associations between home environmental factors and childhood eczema ever, and related symptoms including itchy rash (IR) and being awakened by itchy rash at night (awake by IR) in 4 cities located in different regions of China, based on cross-sectional investigations during 2010–2012. We used two-step analysis to explore the associations between influencing factors and eczema/related symptoms: first, group Least Absolute Shrinkage and Selection Operator (LASSO) was conducted to identify important factors among a list of candidates; then, the associations in total study population and in each city were estimated using logistic regression. We found these home environmental factors to be risk factors for eczema or related symptoms: large residence size, shared room, air cleaner at home, abnormal smell, perceived dry air, visible mold or damp stains, cooking with coal or wood, painted wall, incense, mice, new furniture during pregnancy, abnormal smell at birth, window condensation at birth and environmental tobacco smoke at birth. Environmental protective factors were rural house location and window ventilation. Associations of factors with eczema/related symptoms differed across cities. For example, air conditioning was protective for eczema in Beijing and awakening by IR in Shanghai with ORs of 0.70 (95%CI: 0.52, 0.95) and 0.33 (95%CI: 0.14, 0.81) respectively, but not significant in other cities. Our results have implications for improving home environments to reduce the risk of childhood eczema/related symptoms in different regions of China.

Early-life exposure to air pollution associated with food allergy in children: Implications for ‘one allergy’ concept

BackgroundThe rapid increase of food allergy (FA) has become the “second wave” of allergy epidemic and is now a major global public health concern. Mounting evidence indicates that early life exposure to air pollution is associated with the “first wave” of allergy epidemic (including asthma, allergic rhinitis and eczema) in children, but little is known about its association with FA. ObjectivesWe hypothesize FA has triple exposure pathways, gut-skin-airway, and investigate the effects of airway exposure to outdoor and indoor air pollution on childhood FA. MethodsA cohort study of 2598 preschool children aged 3–6 years old was conducted in Changsha, China. The prevalence of FA was surveyed using a standard questionnaire by International Study of Asthma and Allergies in Childhood (ISAAC). Exposure to indoor air pollution was assessed by four indicators: new furniture, redecoration, mold or dampness, and window condensation. Exposure to outdoor air pollution was evaluated by the concentrations of PM10, SO2 and NO2, which were obtained from the monitored stations. Both prenatal and postnatal exposure windows were considered. The association between exposure to outdoor/indoor air pollution and childhood FA was estimated by multiple logistic regression models using odds ratio (OR) and a 95% confidence interval (CI). ResultsA total of 14.9% children reported FA. The prevalence was significantly associated with exposure to indoor air pollution, OR (95% CI) = 1.93 (1.35–2.75) for prenatal exposure to mold/dampness and 1.49 (1.07–2.10) and 1.41 (1.04–1.89) respectively for postnatal exposure to new furniture and window condensation. The prevalence of FA was also associated with prenatal and postnatal exposure to outdoor air pollution, particularly the traffic-related air pollutant NO2, with adjusted ORs (95% Cls) respectively 1.24 (1.00–1.54) and 1.38 (1.03–1.85) per interquartile range (IQR) increase. Sensitivity analysis showed that the association between outdoor/indoor air pollution and childhood FA was significant only in young children aged 3–4 years. ConclusionEarly-life exposure to high levels of outdoor and indoor air pollution in China due to the rapid economic growth and fast urbanization in the past decades may contribute to the rapid increase of food allergy (FA) in children. Our study indicates that, in addition to gut and skin, airway may be a new route of food sensitization. Air pollution leads to the first and second waves of allergy epidemics, suggesting a concept of ‘one allergy’ disease.

Early life exposure to outdoor air pollution and indoor environmental factors on the development of childhood allergy from early symptoms to diseases

BackgroundThe prevalence of childhood allergies has increased during past decades leading to serious hospitalization and heavy burden worldwide, yet the key factors responsible for the onset of early symptoms and development of diagnosed diseases are unclear. ObjectiveTo explore the role of early life exposure to ambient air pollution and indoor environmental factors on early allergic symptoms and doctor diagnosed allergic diseases. MethodsA retrospective cohort study of 2598 preschool children was conducted at 36 kindergartens in Changsha, China from September of 2011 to February of 2012. A questionnaire was developed to survey each child's early onset of allergic symptoms (wheeze and rhinitis-like symptoms) and doctor diagnosis of allergic diseases (asthma and rhinitis) as well as home environments. Each mother's and child's exposures to ambient air pollutants (PM10, SO2, and NO2) and temperature were estimated for in utero and postnatal periods. The associations of early symptoms and diagnosed diseases with outdoor air pollution and indoor environmental variables were examined by logistic regression models. ResultsChildhood early allergic symptoms (33.9%) including wheeze (14.7%) and rhinitis-like symptoms (25.4%) before 2 years old were not associated with outdoor air pollution exposure but was significantly associated with maternal exposure of window condensation at home in pregnancy with ORs (95% CI) of 1.33 (1.11–1.59), 1.30 (1.01–1.67) and 1.27 (1.04–1.55) respectively, and was associated with new furniture during first year after birth with OR (95% CI) of 1.43 (1.02–2.02) for early wheeze. Childhood diagnosed allergic diseases (28.4%) containing asthma (6.7%) and allergic rhinitis (AR) (7.2%) were significantly associated with both outdoor air pollutants (mainly for SO2 and NO2) during first 3 years and indoor new furniture, redecoration, and window condensation. We found that sex, age, parental atopy, maternal productive age, environmental tobacco smoke (ETS), antibiotics use, economic stress, early and late introduction of complementary foods, and outdoor air pollution modified the effects of home environmental exposure in early life on early allergic symptoms and diagnosed allergic diseases. ConclusionOur study indicates that early life exposure to indoor environmental factors plays a key role in early onset of allergic symptoms in children, and further exposure to ambient air pollution and indoor environmental factors contribute to the later development of asthma and allergic rhinitis.

Rhinitis in Japanese students – associations with window pane condensation, recent indoor painting, wooden home and dog allergen at school

ABSTRACT We studied risk factors for rhinitis in Japanese homes and schools. A questionnaire was sent to students in four schools (12–15 y age), 1048 (99.2%) participated. Crowdedness and furry pet allergens were measured in their classrooms. Household environment data was collected by a questionnaire. Risk factors were identified by multi-level logistic regression with mutual adjustment. The prevalence of current rhinitis was 60.3%, current rhinoconjunctivitis 24.4% and weekly rhinitis 29.5%. Window condensation (AORs1.69–1.90) and indoor painting (AORs1.72–1.76) at home were associated with rhinitis. The association between painting and rhinitis was stronger in girls (interaction p = 0.002) and in wooden homes (interaction p = 0.05). Dog allergen (Can f 1) in classroom air was associated with rhinitis (p = 0.04). In conclusion, window pane condensation and indoor painting can be household risk factors for rhinitis and dog allergen may be a risk factor in Japanese schools. Girls can be more sensitive to emissions from indoor paint than boys.

Outdoor Air Pollution and Indoor Window Condensation Associated with Childhood Symptoms of Allergic Rhinitis to Pollen

Pollen is the main factor causing asthma and allergic rhinitis (AR). However, the key indoor and outdoor factors associated with childhood symptoms of allergic rhinitis (SAR) to pollen are unclear. We investigate the association of exposure to outdoor air pollution and indoor environmental factors with childhood SAR to pollen and consider SAR to pollen in different seasons. A cross-sectional study of 2598 preschool children aged 3–6 was conducted in Changsha, China (2011–2012). The prevalence of SAR to pollen in children and information on indoor environmental factors were obtained by questionnaire. Children’s exposure to outdoor air pollutants (PM10, SO2, and NO2) was estimated from the monitored concentrations. The association of exposure to indoor environmental factors and outdoor air pollution with childhood SAR to pollen was estimated by multiple logistic regression models using odds ratio (OR) and a 95% confidence interval (CI), and the relationship between outdoor air pollutants and childhood SAR to pollen was investigated using restricted cubic splines. We found that early-life and current exposure to outdoor air pollution were significantly associated with childhood SAR to pollen in autumn, including exposure to SO2 one year before conception (OR = 1.60, 95% CI = 1.08–2.37) and during entire pregnancy (OR = 1.49, 95% CI = 1.01–2.20) periods, exposure to PM10 during the current period (OR = 1.78, 95% CI = 1.07–2.96), and exposure to NO2 during the early-life (one year before conception and entire pregnancy) and current periods with ORs (95% CI) of 1.72 (1.10–2.71), 1.82 (1.17–2.83), and 1.94 (1.11–3.40), respectively. Further, we found significant associations of both prenatal and postnatal exposure to window condensation with childhood SAR to pollen, with ORs (95% CI) = 1.37 (1.05–1.77) and 1.38 (1.02–1.88), respectively. We encourage SAR to pollen sufferers to stay indoors due to outdoor air pollution and higher pollen concentration outdoors, but indoor ventilation should be maintained.

Effect of Preconception, Prenatal and Postnatal Exposure to Ambient Air Pollution on Laryngitis in Southern Chinese Children

Environmental exposure is considered to be a main triggering factor of laryngitis, a common upper respiratory tract infection, especially in developing countries. However, unclear detrimental air pollutants and lack of understanding on their early-life exposure and laryngitis warrant further investigation. Therefore, a retrospective cohort including 2328 preschool children was conducted during 2015–2016 in Shenzhen, China. We measured ambient air quality of PM10, SO2 and NO2 in 12 monitoring stations, and obtained childhood laryngitis prevalence and confounding covariates by questionnaire. Multiple logistic regression analysis showed that the lifetime prevalence of childhood laryngitis (12.2%) was associated with an interquartile range increase in late preconception (adjusted odds ratio: 1.43, 95% confidence interval: 1.06‒1.92), prenatal (1.35, 1.02–1.79) and early-postnatal (1.32, 1.11‒1.57) exposure to SO2. Sensitivity analysis revealed that this relationship appeared more obvious among boys without parental atopy, mold/damp stains, or window condensation. Nevertheless, there was no evidence for the association between early-life PM10 and NO2 exposure and childhood laryngitis. These findings suggest that early-life exposure to SO2 significantly increases risk of childhood laryngitis. Preventive measures need to be implemented to mitigate industrial air pollution.

Effect of outdoor air pollution and indoor environmental factors on small for gestational age

BackgroundSmall for gestational age (SGA) is a major public health problem that affects 32.4 million infants worldwide and its prevalence is increasing rapidly in new-borns. However, the key risk factors and their exposure time window on the development of SGA are unclear. ObjectiveWe aim to investigate the association between exposure to outdoor air pollution and indoor environmental factors during which critical timing window and SGA, and to evaluate which specific personal factors modify this association. MethodsA retrospective cohort study of 3509 infants was conducted in Changsha, China during 2011–2012. A questionnaire survey was performed to obtain the formation on infant's birth outcomes and prenatal exposure of indoor environmental factors containing parental (maternal and/or paternal) smoking, new furniture, house redecoration, mold or dampness, window condensation, and keeping dogs in gestational age. Intrauterine exposure to industrial air pollutant (SO2), traffic-related air pollutant (NO2) and inhalable particulate matter (PM10) was estimated during three trimesters and entire pregnancy. Associations between outdoor air pollutants and indoor environmental factors and SGA, term SGA (TSGA) and preterm SGA (PSGA) were assessed by multiple logistic regression model in terms of odds ratio (OR) and 95% confidence interval (CI). ResultsPrevalence of SGA (5.2%) and TSGA (4.9%) were significantly associated with intrauterine exposure to outdoor SO2 during the entire gestational age with adjusted ORs (95% CI) of 1.08 (1.01–1.15) and 1.08 (1.00–1.15) for per 10 μg/m3 increase in SO2 exposure after adjusting for the covariates, indoor environmental factors, and outdoor air temperature, and PSGA prevalence (0.3%) was significantly related with PM10 exposure during whole pregnancy with odds = 2.21 (1.08–4.51). However, no association was observed for traffic-related air pollutant NO2 exposure. Specifically, the association was more significant for SO2 exposure during the 1st and/or 2nd trimester. We further found that TSGA and PSGA were associated with indoor exposure to parental smoking and new furniture, respectively, ORs (95% CI) = 1.46 (1.00–2.11) and 10.95 (1.46–81.95). We observed that the odds of SGA and TSGA attributed to SO2 exposure in the first two trimesters was only significant among families with parental smoking and new furniture in gestation. Sensitivity analysis showed that infants with female sex and born in cold months were more susceptible to the effect of outdoor SO2 exposure during the first two trimesters and entire gestational age on SGA and TSGA. On the other hand, infants born in the cold season and by a younger mother were more sensitive to the effect of indoor parental smoking in utero on SGA and TSGA. ConclusionMaternal exposure to industry-related air pollution and indoor environmental risk factors during pregnancy, particularly during the first two trimesters, significantly increased SGA risk, and some specific personal factors could modify these associations.

Furry pet-related wheeze and rhinitis in pre-school children across China: Associations with early life dampness and mould, furry pet keeping, outdoor temperature, PM10 and PM2.5

BackgroundFew Chinese population studies exist on early life risk factors for furry pet allergy. ObjectivesWe studied childhood respiratory symptoms when in contact with furry pets in relation to early life exposure. Moreover, we studied similar environmental associations for rhinitis not related to furry pets. MethodsChildren aged 3–6 y from day care centres in seven Chinese cities participated (N = 39,782). Parents answered a questionnaire on home environment and children’s health, including rhinoconjunctivitis and wheeze when in contact with furry pets, and diagnosed rhinitis. Prenatal and postnatal outdoor temperature, PM2.5, PM10, and NO2 were calculated using data from monitoring stations. Associations were estimated by multilevel logistic regression. ResultsTotally 2% had cats, 4% dogs, and 3.2% had rhinoconjunctivitis or wheeze when in contact with furry pets (FP symptoms). Moreover, 1.1% had furry pet related diagnosed rhinitis and 7.5% had diagnosed rhinitis not related to furry pets (other diagnosed rhinitis). Prenatal PM2.5 and PM10, especially in second trimester, and a colder climate were risk factors for FP symptoms. ETS, dampness and mould, condensation on windows in wintertime, and cats and dog keeping were associated with FP symptoms. Breast feeding and frequent window opening were protective. Similar indoor associations were found for furry pet related diagnosed rhinitis. ETS, dampness and mould, window condensation, urbanization and mechanical exhaust ventilation were risk factors for other diagnosed rhinitis. Cooking with an electric stove and early life exposure to animals (cats, dogs, farm environment during pregnancy) were protective for diagnosed rhinitis not related to furry pets. ConclusionsPrenatal outdoor PM10 and PM2.5 can be risk factors for symptoms suggestive of furry pet allergy. Early life dampness and mould can be risk factors for rhinitis related and not related to furry pets. Exposure to animals (cats, dogs, farm environment) may reduce diagnosed rhinitis not related to furry pets.

Home environmental and lifestyle factors associated with asthma, rhinitis and wheeze in children in Beijing, China

BackgroundThe prevalence of asthma and allergic diseases has increased rapidly in urban China since 2000. There has been limited study of associations between home environmental and lifestyle factors with asthma and symptoms of allergic disease in China. MethodsIn a cross-sectional analysis of 2214 children in Beijing, we applied a two-step hybrid Least Absolute Shrinkage and Selection Operator (LASSO) algorithm to identify environmental and lifestyle-related factors associated with asthma, rhinitis and wheeze from a wide range of candidates. We used group LASSO to select variables, using cross-validation as the criterion. Effect estimates were then calculated using adaptive LASSO. Model performance was assessed using Area Under the Curve (AUC) values. ResultsWe found a number of environmental and lifestyle-related factors significantly associated with asthma, rhinitis or wheeze, which changed the probability of asthma, rhinitis or wheeze from −5.76% (95%CI: −7.74%, −3.79%) to 27.4% (95%CI: 16.6%, 38.3%). The three factors associated with the largest change in probability of asthma were short birth length, carpeted floor and paternal allergy; for rhinitis they were maternal smoking during pregnancy, paternal allergy and living close to industrial area; and for wheeze they were carpeted floor, short birth length and maternal allergy. Other home environmental risk factors identified were living close to a highway, industrial area or river, sharing bedroom, cooking with gas, furry pets, cockroaches, incense, printer/photocopier, TV, damp, and window condensation in winter. Lifestyle-related risk factors were child caretakers other than parents, and age<3 for the day-care. Other risk factors included use of antibiotics, and mother’s occupation. Major protective factors for wheeze were living in a rural/suburban region, air conditioner use, and mother’s occupation in healthcare. ConclusionsOur findings suggest that changes in lifestyle and indoor environments associated with the urbanization and industrialization of China are associated with asthma, rhinitis, and wheeze in children.

Combined effects of traffic air pollution and home environmental factors on preterm birth in China

BackgroundAlthough mounting evidence have linked traffic-related air pollution (TRAP) with increased risk of preterm birth (PTB), whether it can interact with indoor environmental factors remains unknown, and its window(s) susceptibility at the stage of gestation is unclear. ObjectiveTo explore PTB risk for prenatal exposure to traffic-related air pollution and home environmental factors during pregnancy, so as to identify critical window(s) in the combined effect of traffic air pollution and main home environmental factor(s) on PTB development. MethodsA retrospective cohort study of 3,509 preschool children was performed in Changsha, China during 2011–2012. The PTB prevalence was reported by the parents based on a questionnaire. We estimated each mother's exposure to traffic-related air pollutant NO2 in different windows of gestation, including conception month, three trimesters, birth month, and whole gestation. Maternal exposure to home environmental factors was considered by renovation (new furniture/redecoration) in pregnancy, and mold/damp stains and window condensation during perinatal period. Associations of PTB with both ambient NO2 and home environmental factors, and their interactions on PTB were evaluated by logistic regression models using odds ratio (OR) with 95% confidence interval (CI). ResultsTraffic air pollutant NO2 exposure in utero was significantly associated with PTB, with adjusted odds ratio (OR) (95% CI) of 1.41 (1.00–1.98) for an IQR increase in NO2 exposure during whole pregnancy, particularly in the conception month and 1st trimester. We further found a positive relationship between perinatal exposure to mold/damp stains in the homes and PTB, OR (95% CI) = 1.73 (1.04–2.90). Especially, we detected a significant interaction between outdoor NO2 and indoor mold/damp stains on PTB risk. Male and female foetus were respectively more susceptible to perinatal mold/dampness at home and outdoor NO2 exposure in early gestation. ConclusionOur finding indicates that both outdoor traffic air pollutant and indoor mold/dampness play key roles in PTB development, and their interaction effect in early pregnancy significantly increases PTB risk.

Modern life makes children allergic. A cross-sectional study: associations of home environment and lifestyles with asthma and allergy among children in Tianjin region, China.

In the past 60years, the prevalences of asthma and allergy among children have increased around the world. Neither genetic nor outdoor environmental factors can explain this increase. We performed a cross-sectional study of 7366 children in Tianjin, China, on associations of home environment and lifestyles with asthma and allergy. The prevalences of diagnosed asthma, rhinitis and eczema among 0- to 8-year-old children in the Tianjin area were 4%, 9% and 39%. Home environment and lifestyle, together with infections,were strong risk factors.For asthma and allergy, the population attributable fraction (PAF) due to modern floors and wall coverings (i.e., laminated wooden floors and painted walls compared to tile floors and lime-coated walls) was 22%. Window condensation in winter and air conditioner use in summer, both of which are proxies for less ventilation, accounted for 7-17% of rhinitis and eczema. Cesarean delivery accounted for 10% of eczema symptoms. We developed a modern life index from appropriate home characteristics and lifestyle and food consumption habits and found it to have a clear dose-response relationship with asthma and allergy in Tianjin children. The results indicate that a "modern" home environment together with a modern lifestyle is associated with increased prevalences of asthma and allergies among children. Appropriate indoor environmental interventions and education of children's caregivers are important in the management of childhood asthma and allergy.

Case Study on the Inspection and Repair of Window Condensation Problems in a New Apartment Complex

AbstractDisputes and repairs due to window condensation problems frequently occur after the completion of apartments. However, most repairs are performed individually and confidentially by construc...

Preconceptional, prenatal and postnatal exposure to outdoor and indoor environmental factors on allergic diseases/symptoms in preschool children

BackgroundEnvironmental factors have been found to be associated with allergic diseases, but it is unclear which environmental factor during which exposure window causes what kind of allergic diseases. ObjectivesWe investigated association between exposure to some predominant outdoor and indoor environmental factors during preconceptional, prenatal, and postnatal periods and allergic diseases/symptoms in 2598 children in China. MethodsChildren's lifetime incidence of allergic diseases and current prevalence of allergic symptoms and exposure to indoor new furniture/redecoration and mold/dampness was surveyed by a questionnaire. Exposure to outdoor air pollutants was estimated by the concentrations measured at air quality monitoring stations. Multiple logistic regression model was used to evaluate the associations between outdoor air pollutants and indoor environmental factors and allergic diseases (asthma, allergic rhinitis, and eczema) and symptoms (wheezing, night cough, and rhinitis-like). ResultsWe found that preconceptional, prenatal, and postnatal exposure to outdoor industrial and traffic air pollutants were significantly associated with increase in the risk of childhood asthma, and also positively associated with allergic rhinitis and eczema. However, we cannot distinguish the effect of outdoor air pollutants and exposure windows because of their high correlations. New furniture was associated with eczema and allergic rhinitis during postnatal exposure, but redecoration associated with asthma and eczema during prenatal exposure. Indoor visible mold/damp stains was significant for eczema during prenatal exposure and asthma during postnatal exposure respectively, but window condensation was significant for all childhood allergic diseases during both prenatal and postnatal exposures. Allergic symptoms in children were found to be associated with exposure to indoor factors only. ConclusionsAssociations between outdoor air pollutants and indoor environmental factors and childhood allergic diseases/symptoms were divergent and related to the timing of exposure.

공동주택 창호 결로하자 진단 및 보수 사례

공동주택 창호 결로하자 진단 및 보수 사례

The home environment of junior high school students in Hyogo, Japan – Associations with asthma, respiratory health and reported allergies

Associations between home environment factors and respiratory symptoms, and reported allergies among junior high school students in Kobe, Japan ( N = 1048) were investigated in the present study. These were mutually adjusted for age, sex, type of school (private/local) and their significant exposures to the environment. Totally 13.4% of students reported to have doctor's diagnosed asthma, 9.9% had wheeze and 50.1% had attacks of daytime breathlessness during past 12 months, 25.7% of students reported that they had pollen allergy, 8.8% had cat allergy and 6.1% had dog allergy. Totally 29.4% of students were living in a wooden house and during past 12 months, 18% of students reported that their homes had signs of dampness, 38.2% of homes had window condensation in winter and 7.8% of homes had indoor painting. Window condensation was associated with wheeze (odds ratio (OR) = 1.54; 95% confidence interval (CI) 1.01–2.34), daytime breathlessness (OR = 2.02; 95% CI 1.56–2.63), airway infection during past 12 months (OR = 1.66; 95% CI 1.17–2.37), cat allergy (OR = 1.63; 95% CI 1.05–2.54); mould allergy (OR = 1.84; 95%CI 1.08–3.12) and pollen allergy (OR = 1.54; 95% CI 1.15–2.06). Recent indoor painting was associated with daytime breathlessness (OR 1.83; 95% CI 1.12–3.00), dog allergy (OR = 2.23; 95% CI 1.02–4.85) and mould allergy (OR = 2.43; 95% CI 1.14–5.17). Living in a wooden house was associated with dog allergy (OR = 2.17; 95% CI 1.18–4.00) and mould allergy (OR = 1.98; 95% CI 1.04–3.76). In conclusion, in Japanese homes, the window condensation in winter, recent indoor painting and living in a wooden house could contribute to the increased risk of respiratory symptoms and allergies for young Japanese school children.

Application of a Whole-Building Hygrothermal model in energy, durability, and indoor humidity retrofit design

A building shall be classified as high performance building if it is energy efficient and durable and at the same time provides comfortable and healthy indoor environment for occupants. To achieve this objective, the hygrothermal performance of alternative building designs should be evaluated based on the simultaneous analysis of these three functional requirements rather than separately. In this article, a Whole-Building Hygrothermal model is used for evaluation of various retrofit design parameters that potentially enhance the overall performance of an existing residential house. The retrofit options considered in this study include changes to the reference house’s ventilation rate and operation, windows, insulation level, and various combinations of these options. Energy efficiency, building envelope and moisture management potential, indoor humidity control, and window condensation potentials are considered to be the four performance indicators in searching for a retrofit option that delivers an optimal performance. The hygrothermal simulation results indicate that changing a design parameter to improve one of the design goals may result in less optimal results in the other one or both goals, or even in some cases result in severe negative consequences.

The Home Environment of Japanese Female University Students - Association with Respiratory Health and Allergy

A study was undertaken to determine the association between the home environment along with the respiratory and allergy symptoms reported among female university students in Japan (N =153). A multiple logistic regression was applied for the determination and the study was controlled based on the age of the students, whether the student smokes and history of asthma/allergy suffering in parents. The characteristics of the population were: 15.7% are diagnosed asthma, 56.9% suffered pollen allergy, 15.7% cat allergy, 11.1% dog allergy, 25.0% wheeze in breathing, 24.2% suffered daytime breathlessness and 9.3% suffered nocturnal attacks of breathlessness. Evaluated characteristics were: 41.2% had a pet at home, 21.6% environmental tobacco smoke (ETS), 20.9% current dampness or moulds, 6.6% recent indoor painting, 7.2% new floor material, and 56.2% window condensation at home in winter. Wheeze was more common in concrete houses (OR = 3.33; p&lt;0.05) and homes with water leakage and moulds infestation in the last 5 years (OR = 3.75; p&lt;0.05), window condensation (OR=2.93; p&lt;0.05) and ETS (OR=3.04; p&lt;0.05). Nocturnal breathlessness was related to current building dampness (OR = 7.48; p&lt;0.05), in particular to floor dampness. Furry pet allergy was more common in newer ( p&lt;0.05) and newly painted homes (OR = 6.59; p&lt;0.05). Airway infections were more common in homes with new floor material (OR=4.19; p&lt;0.05). In conclusion, asthma, airway infections and allergies were common among female university students and related to home environmental exposures.

Indoor factors associated with concentrations of house dust mite allergen, Der p 1, in a random sample of houses in Norwich, UK.

Studies of house dust mite allergen concentrations suggest large variations both within and between homes. It is likely that different household characteristics influence allergen levels in different locations within the house. To investigate household characteristics associated with higher concentrations of house dust mite allergen in a random sample of houses. Information on indoor environment was obtained from 158 adults aged 20-44. Dust samples were collected from their living room floor, bedroom floor and mattress. Concentrations of Der p 1, the major allergen from the house dust mite Dermatophagoides pteronyssinus, were measured by monoclonal antibody immunoassay. Associations between mite allergen concentrations and household characteristics were examined using censored-normal regression models. Factors that were related to Der p 1 (P </= 0.2) in univariate analyses were included in multivariable regression models. Der p 1 was not detected in any location in 10 (6.3%) houses. Geometric mean concentrations of Der p 1 were 1.9 microg/g in living room floor dust, 1.7 microg/g in bedroom floor dust and 2.0 microg/g in mattress dust. Approximately 25% of living room floor and mattress, and over 30% of bedroom floor samples had Der p 1 concentrations greater than 10 microg/g. Household characteristics associated with Der p 1 concentrations in both living room and bedroom were floor level, extractor fan in the kitchen, and age of carpet. Living room Der p 1 concentrations were also associated with gas oven/hob, window condensation, open fires, vacuum cleaner type, smokers in the house and age of house. Bedroom Der p 1 concentrations were also associated with use of blankets and wash temperature of bedding. Mattress Der p 1 concentrations were associated with window condensation, concrete bedroom floor and age of mattress. Different household characteristics were associated with high Der p 1 concentrations in different parts of the house. These findings are relevant to design of allergen avoidance regimes or formulation of policy recommendations for reduction of disease associated with allergen exposure.

Predicting window condensation potential for a large viewing gallery

A numerical method for predicting the likelihood that moisture may condense on the glazed fenestration of a large air-conditioned viewing gallery is presented. The study is conducted by using a three-dimensional k-ϵ turbulence model and tropical weather data. The relationships between the occurrence of condensation, ambient air conditions and the time of day are obtained and analysed. The number of hours of moisture condensation on the glass panel that can be expected in a year is estimated. It is found that a 1 °C increase in the temperature of the cool supply air into the air-conditioned space can significantly reduce the occurrence of condensation.

Free convection analysis of a window cavity and its longitudinal temperature profile

Window condensation in dwellings and offices can be very troublesome. It not only obstructs the view through the windows, but also runs off, accelerating the deterioration of paintwork, frames and furniture. In the present article, measurements and modelling techniques have been used to study the longitudinal temperature variation of double-glazed windows. It has been shown, herein, that the above temperature variation is primarily due to the buoyancy driven flow of gas within the sealed enclosure. This flow of gas alternates between the heated inward and cooled outward panes. The present work provides a physical model which can be used to calculate, with precision, the temperatures along the height of double-glazed windows. This method may be a prerequisite for the quantification of condensation, so commonly encountered in the European and North American climates.