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This study developed a prediction method to determine the distribution of phthalate esters (PAEs) in indoor dust. A gradient boosting decision tree model (GBRT) was trained by using 267 samples in Shanghai, including PAEs concentrations in indoor dust and data obtained from continuous monitoring, as well as the survey of indoor environment. Environmental exposure, residents' lifestyle, and building characteristics data were collected from 8 cities in China. Based on this, the well-trained GBRT model accurately predicted PAEs concentrations, with goodness of fit (R 2 ) > 0.94, mean absolute error (MAE) approaching 0, and mean squared error (MSE) approaching 0. This study identified key relationships between input parameters and PAEs concentrations. The average increment of PAEs concentration was greater than 50 % when using more than 2 electronic devices in bedroom. Diisobutyl phthalate (DiBP) concentration increased by approximately 200 % when cleaning frequency was less than once every fortnight. Bis (2-ethylhexyl) phthalate (DEHP) concentration increased by over 43 % when dampness-related exposure indicators exceeding 3, and by up to 74 % with extensive usage of polyvinyl chloride (PVC) floorings. Furthermore, the study found higher PAEs concentrations in southern China compared to northern cities. • Apply multidisciplinary method to study the factors affecting the differences in indoor phthalate distribution. • Set up a gradient boosted regression trees model to predict the concentration of phthalate and evaluate the result. • Predict and analyze the distribution of phthalate in eight typical cities in China, providing a data support for impacting assessment of human health. • Provide a theoretical support and scientific method for predicting concentration of phthalate in dust in children's bedroom, with a high popularization value. [ABSTRACT FROM AUTHOR]

Abstract In 2013–2014, we carried out a case-control study in Shanghai, China and collected dust samples from 453 children's beddings (pillow and mattress). Here we investigated associations of bed dust mites (Der p 1 and Der f 1) with childhood health outcomes. These dust mites were analyzed by enzyme-linked immune-sorbent assay (ELISA). The child's health outcomes were reported by parents. Der f 1 concentration among cases were significantly higher than controls for current rhinitis and eczema, but Der p 1 concentration among cases were significantly lower than controls for lifetime-ever croup and asthma. In the multivariate logistic regression analyses, Der p 1 (increment: 0.98 μg/g) and Der f 1 (0.28 μg/g) were associated with the increased odds of dry cough (Der p 1: adjusted odds ratio (AOR), 95% confidence interval (CI): 1.48, 1.01–2.17, p -value: 0.047; Der f 1: 1.52, 1.09–2.12, 0.013) and rhinitis (Der p 1: 1.44, 1.05–1.97, 0.025; Der f 1: 1.25, 0.98–1.60, 0.078). Der f 1 (increment: 0.28 μg/g) had significant associations with the decreased odd of lifetime-ever asthma (OR, 95%CI: 0.75, 0.58–0.97). Significantly higher proportions of families with habits for frequently bed-cleaning were found among cases than among controls according to the most studied illnesses. Our results indicate that exposure to bed dust Der p 1 and Der f 1 could be risk factors for childhood allergic symptoms. Avoidance behaviors with respect to household dust mites among families with case children perhaps mask the real associations of these dust mites with childhood health outcomes in the retrospective case-control study. Highlights • We analyzed two dust mites (Der p 1 and Der f 1) in beddings for 453 Shanghai Children. • Higher levels of Der p 1 and Der f 1 associated with increased odds of current dry cough and rhinitis. • Der f 1 could have stronger associations with allergic symptoms in childhood than Der p 1. • Family avoidance behaviors for bed dust mites could mask the studied associations. [ABSTRACT FROM AUTHOR]

During March 2013–December 2014, we conducted a field study in Shanghai, China. A total of 409 children's bedrooms had valid data for formaldehyde which was continuously measured for 24 h. The daily 24 h-averaged and night 6 h-averaged (00:00–06:00) concentrations were 21.5 μg/m 3 and 22.2 μg/m 3 , respectively. Bedrooms with mechanical ventilation had lower formaldehyde concentrations than those with natural ventilation. In the multiple logistic regression analyses, compared to children in the first quartile of 24 h-averaged formaldehyde, children in fourth quartile had significantly lower odds of lifetime-ever food allergy (adjusted odds ratio (OR), 95% confidence interval (CI): 0.39, 0.16–0.97) and current rhinitis (0.39, 0.18–0.86), but children in the third quartile had significantly higher odd of current common cold (≥3 times) (2.42, 1.02–5.77). Among autumn-inspected children, formaldehyde exposure had significant associations with current common cold (≥3 times) (adjusted OR, 95%CI for 24 h-averaged: 4.88, 1.18–20.21 in increment of 11.7 μg/m 3 ; for 6 h-averaged: 4.41, 1.07–18.19 in increment of 15.7 μg/m 3 ). Significantly more families with case children used household mechanical ventilation and air cleaner than families with control children. Our results indicate that household formaldehyde exposure may increase the risk of childhood common cold. Since it is impossible that formaldehyde exposure in higher concentrations could decrease the risk of current rhinitis and other illnesses, we infer that those “negative” associations could be confounded by the potential behaviour changes for avoidance of household formaldehyde exposure among families with case children. [ABSTRACT FROM AUTHOR]

Few studies have estimated the effects of dampness-related exposures and its interaction effects with poor household ventilation on common colds of preschool children. During April 2011–April 2012, we conducted a cross-sectional survey on home environment and childhood health and collected 13,335 parents-reported questionnaires of 4–6 year-old children in Shanghai, China. In this paper, we investigated associations between the incidence and duration of common colds among these children during the past 12 months before the survey and frequency of opening windows, as well as household dampness-related exposures (indicated by six dampness indicators). Significantly higher incidence (≥3 times) and longer duration (≥2 weeks) of common cold were found among children with than without these dampness exposures (p-value <0.01 for mold spots and p-value <0.001 for all other indicators). The number of dampness-related indicators had a positive and strong dose-response relationship with common colds (p-trend <0.01). Low frequency of ventilation was also a risk factor for children common colds. After adjusted for the potential confounders in the multiple logistic regression analyses, all dampness-related indicators were significantly associated with the increased odds of common colds and the highest odds ratios was 1.21 (95% CI: 1.16–1.27). We also found that dampness-related exposures and household ventilation habits (p-value for interaction <0.001) had a strong interaction effect on the incidence and duration of common cold. The stratified analysis of ventilation condition displays that the influence of dampness-related exposures has been modified by ventilation. Therefore, good household ventilation habits may have an effect of modification for dampness-related exposures. [ABSTRACT FROM AUTHOR]

During 2011–2012, we conducted a cross-sectional study and collected 13,335 parent-reported questionnaires for 4-6 year-old children in Shanghai, China. In this study, we investigated associations of LC-HTRH (Living Close to High Traffic Roads or Highways within 200 m of the residence) with childhood health outcomes. In the multiple logistic regression analyses, LC-HTRH was significantly associated with lifetime-ever doctor-diagnosed asthma (adjusted OR, 95% CI: 1.40, 1.16–1.70). LC-HTRH and bedroom floor level had significant interaction effects on lifetime-ever asthma attack and eczema and past-year eczema. In the subanalyses, LC-HTRH was significantly associated with lifetime-ever asthma (1.52, 1.11–2.09) and asthma attack (1.69, 1.11–2.56) among children who lived on the 4th–6th floors. LC-HTRH was significantly associated with the increased odds of lifetime-ever asthma and past-year rhinitis in summer, autumn, and winter among children whose bedroom windows were opened often. Furthermore, more significant associations between LC-HTRH and the studied outcomes were found among children who both lived in low floor levels and came from families who often opened bedroom windows during night than others. Except for lifetime-ever asthma, no significant associations were found between LC-HTRH and all studied outcomes among children from families who did not often open bedroom windows during night in the different floor levels. This study indicates that LC-HTRH might be associated with part of childhood health outcomes. When ambient air is polluted, increasing bedroom ventilation might lead household air quality at low-medium levels worse, and thus increase odds of some childhood allergic and respiratory problems. [ABSTRACT FROM AUTHOR]

From March 2013 to December 2014, we collected air samples of airborne culturable fungi from 454 residences with young children (mean age: 6.9 years-old) in Shanghai, China. We also measured indoor air temperature and relative humidity, and compiled information regarding dwelling characteristics, lifestyle habits, and dampness-related indicators. Mean concentrations (mean ± SD) of culturable fungi in the child's bedrooms ( n = 445) and in the living rooms ( n = 436) were 310 ± 313 (range: 6–3184) cfu/m 3 and 300 ± 288 (range: 19–3044) cfu/m 3 , respectively. The concentrations of airborne fungi were higher in spring and winter than in other seasons, but were only slightly correlated with indoor air temperature and relative humidity in any season. Higher levels of airborne culturable fungi in the child's bedroom were significantly associated with location in a rural area, constructed before 2000, ground/top floor of the residential building, and building area <10 m 2 . Among those residences inspected in winter, rooms with poor ventilation and residences with spiders and cockroaches, damp spots and moldy spots on the wall surface were associated with higher concentrations of indoor airborne culturable fungi. We found that the household level of airborne fungi was acceptable in most of Shanghai's current residences. The possibility of indoor airborne culturable fungi during cold spring and winter requires more attention than in other seasons. Preventing dampness-related damage, improving indoor ventilation, and maintaining a dwelling free of spiders and cockroaches may decrease indoor level of airborne culturable fungi. [ABSTRACT FROM AUTHOR]

A total of 15,266 questionnaires from 1 to 8 year-old children was used to investigate the prevalences of home dampness-related indicators and their associations with the respondent's residential characteristics and lifestyle behaviors in Shanghai, China. Most of the questionnaires were filled out by one of the child's parents (69.0% by mother and 24.9% by father). The prevalence of visible mold (VMS) was 7.9%, visible damp stains (VDS) 15.2%, windows pane condensation (WPC) 54.9%, water damage (WD) 11.9%, damp clothing and/or bedding (DCB) 42.0%, and moldy odor (MO) 11.9%, respectively. Questionnaires submitted by the child's mother noted significantly more dampness-related indicators than those submitted by the father and other respondents. Residences on the ground floor or top floor were strongly and positively associated with VMS and VDS in comparison with residences on the other floors of the dwelling building. Keeping fish in the current residence also had significant and positive associations with VDS, WPC, and WD. Having exhaust fan in the bathroom and/or opening the windows of the child’ bedroom, and frequently cleaning rooms was strongly associated with reduced dampness-related indicators in the child’ bedroom. Most of these associations among families without asthmatic children were similar to among the whole samples. Therefore, we concluded that studies regarding to home dampness-related evaluation by questionnaire should carefully considered report bias. Living on the ground floor or top floor and fish-keeping are risk factors for home dampness-related exposures. Improving home ventilation and increasing frequency of home cleaning could effectively reduce these exposures. [ABSTRACT FROM AUTHOR]

Dampness-related exposures have been widely discovered in household, which are associated with childhood health. This study employed the Back-Propagation (BP) neural network to develop prediction models of overall dampness evaluation based on the on-site dampness inspection in 454 families. The trained models were then used to predict the overall dampness exposure in 15,266 families with five parent-reported dampness-related indicators. Two indices, including the overall-dampness- exposure-based (ODEB) score and combination-of parent-reported- based (CPRB) score, were introduced to reflect the household dampness exposure in Shanghai, and were used to build the relationship with different childhood respiratory diseases and allergies. The results indicated that the trained model of BP neural network had a reasonable accuracy with the coefficient of determination R2 greater than 0.5, and the standard deviation ratios were approaching 1.0. Both the ODEB score predicted by trained model and CPRB score were developed based on parent reported dampness indicators in the cross-sectional survey, and were significantly associated with childhood respiratory diseases after adjusting the confounders (AOR >1.3, p < 0.01, SDS factor >0). Exposure-response relationships were also found between the dampness exposure indices and health outcomes. A continuous dampness evaluation index with a reasonable accuracy was proposed based on BP neural network prediction of on-site dampness scoring, which was consistent with the CPRB score, showing an exposure-response relationship with childhood diseases. These findings provide us an approach to predict the household dampness and its related adverse health outcomes. • Dampness exposures are common in residential buildings in China. • Home dampness-related exposure is a risk for childhood allergies and respiratory diseases. • The parent-reported dampness can be linked to the inspector-observed dampness. • There are exposure-response relationships between dampness indicators and children health. • Two developed dampness indices can predict the dampness-related health outcomes. [ABSTRACT FROM AUTHOR]

Abstract: Shanghai International Gymnastics Stadium is the selected object for site-measurement. The site-measurements have been carried out during summer, winter, and the transitional seasons. Their indoor thermal environments were controlled by continuous air-conditioning, intermittent air-conditioning and natural ventilation, respectively. The site-measurement includes outdoor environment (the weather conditions and peripheral hallway), indoor air temperature distribution (the occupant zone temperature, radial temperature near upper openings and the vertical temperature distributions, etc.), and the heat balance of air-conditioning system, etc. It is found that temperature stratification in winter with air-conditioning is most obvious. The maximum difference of vertical temperature is 15°C in winter. The second largest one is 12°C in summer, and less than 2°C in the transitional season. The results of measurements indicate that it is different in the characteristics on energy saving of upper openings during the different seasons. With heat balance measurements, it is discovered that the roof load and ventilated and infiltrated load account for larger percentages in terms of cooling and heating load. In this paper, many discussions on the results of site measurements show some characteristics and regulations of indoor thermal environment in large space building. [Copyright &y& Elsevier]