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We studied time trends in home environment and sick building syndrome (SBS) symptoms in a repeat study in five cities in southern China. Moreover, we studied associations between home environment exposure and SBS symptoms. Parents from randomly selected day care centers were invited. One parent per family answered a questionnaire on the home environment and their own SBS symptoms. Data collection was performed in two surveys in 2010 and 2019 (27,292 participants in 2010 and 32,073 in 2019). We used two-level logistic regression to analyze health associations. Asthma decreased from 1.7% to 1.5% (P < 0.05) but allergic rhinitis increased from 6.5% to 16.4% (P < 0.001). All SBS symptoms decreased from 2010 to 2019 (all P < 0.001). Most aspects of the home environment improved from 2010 to 2019 but there were less cleaning, more cats, dogs, and urbanization in 2019. Redecoration, new furniture, and pests were associated with most types of SBS symptoms, similarly in 2010 and 2019. Environmental tobacco smoke (ETS) was associated with SBS symptoms in 2019 only. In conclusion, prevalence of SBS symptoms among young parents in southern China decreased from 2010 to 2019 but allergic rhinitis increased. Cockroaches, rats, mice, mosquitoes or flies can be consistent biological risk factors for SBS symptoms. Redecoration, buying new furniture and traffic air pollution are other risk factors for SBS symptoms. Daily cleaning, frequently putting bedding to sunshine, and having a fan in the bathroom can be protective factors. ETS is an emerging risk factor for SBS symptoms., The two first authors contributed equally to this work

We investigated associations between dampness in Chinese homes and sick building syndrome (SBS) symptoms and studied the role of climate, family size, cleaning and ventilation for dampness, mould and SBS. A questionnaire survey was done in 2019-2020 among adults in five cities (32349 participants) and data on outdoor climate was collected. Multilevel logistic regression was used to calculate adjusted odds ratios (ORs). In total, 2.2% had rhinitis, 1.8% eye, 1.6% throat and 2.9% skin symptoms, 2.1% headache and 8.7% fatigue (weekly symptoms). Overall, 12.1% reported indoor mould, 5.7% damp bedding, 5.3% mould odour and 33.8% humid air in current home. Mould was associated with all symptoms (ORs 1.86-2.15 for minor mold growth and 1.65-3.45 for major mould growth). Damp bedding was associated with all symptoms (ORs 2.18-2.80 for minor dampness and 2.51-8.03 for major dampness). Mould odour was associated with all symptoms (ORs 1.84-2.77 for sometimes odour and ORs 3.78-7.80 for weekly odour). Perception of humid air was associated with all symptoms. ORs increased by number of dampness signs. Precipitation, outdoor relative air humidity and temperature increased dampness, mould and SBS symptoms. Large family size increased dermal symptoms. Daily floor cleaning, airing in winter, putting bedding to sunshine and mechanical ventilation in the bathroom reduced dampness, mould and SBS symptoms. In conclusion, mould and dampness in Chinese homes can increase rhinitis and SBS-symptoms in a dose-response manner. A warmer and more humid climate can increase, and cleaning and ventilation in the home can decrease dampness, mould and SBS symptoms.

We investigated associations between dampness in Chinese homes and sick building syndrome (SBS) symptoms and studied the role of climate, family size, cleaning and ventilation for dampness, mould and SBS. A questionnaire survey was done in 2019-2020 among adults in five cities (32349 participants) and data on outdoor climate was collected. Multilevel logistic regression was used to calculate adjusted odds ratios (ORs). In total, 2.2% had rhinitis, 1.8% eye, 1.6% throat and 2.9% skin symptoms, 2.1% headache and 8.7% fatigue (weekly symptoms). Overall, 12.1% reported indoor mould, 5.7% damp bedding, 5.3% mould odour and 33.8% humid air in current home. Mould was associated with all symptoms (ORs 1.86-2.15 for minor mold growth and 1.65-3.45 for major mould growth). Damp bedding was associated with all symptoms (ORs 2.18-2.80 for minor dampness and 2.51-8.03 for major dampness). Mould odour was associated with all symptoms (ORs 1.84-2.77 for sometimes odour and ORs 3.78-7.80 for weekly odour). Perception of humid air was associated with all symptoms. ORs increased by number of dampness signs. Precipitation, outdoor relative air humidity and temperature increased dampness, mould and SBS symptoms. Large family size increased dermal symptoms. Daily floor cleaning, airing in winter, putting bedding to sunshine and mechanical ventilation in the bathroom reduced dampness, mould and SBS symptoms. In conclusion, mould and dampness in Chinese homes can increase rhinitis and SBS-symptoms in a dose-response manner. A warmer and more humid climate can increase, and cleaning and ventilation in the home can decrease dampness, mould and SBS symptoms.

We investigated associations between dampness in Chinese homes and sick building syndrome (SBS) symptoms and studied the role of climate, family size, cleaning and ventilation for dampness, mould and SBS. A questionnaire survey was done in 2019-2020 among adults in five cities (32349 participants) and data on outdoor climate was collected. Multilevel logistic regression was used to calculate adjusted odds ratios (ORs). In total, 2.2% had rhinitis, 1.8% eye, 1.6% throat and 2.9% skin symptoms, 2.1% headache and 8.7% fatigue (weekly symptoms). Overall, 12.1% reported indoor mould, 5.7% damp bedding, 5.3% mould odour and 33.8% humid air in current home. Mould was associated with all symptoms (ORs 1.86-2.15 for minor mold growth and 1.65-3.45 for major mould growth). Damp bedding was associated with all symptoms (ORs 2.18-2.80 for minor dampness and 2.51-8.03 for major dampness). Mould odour was associated with all symptoms (ORs 1.84-2.77 for sometimes odour and ORs 3.78-7.80 for weekly odour). Perception of humid air was associated with all symptoms. ORs increased by number of dampness signs. Precipitation, outdoor relative air humidity and temperature increased dampness, mould and SBS symptoms. Large family size increased dermal symptoms. Daily floor cleaning, airing in winter, putting bedding to sunshine and mechanical ventilation in the bathroom reduced dampness, mould and SBS symptoms. In conclusion, mould and dampness in Chinese homes can increase rhinitis and SBS-symptoms in a dose-response manner. A warmer and more humid climate can increase, and cleaning and ventilation in the home can decrease dampness, mould and SBS symptoms.

A questionnaire survey was performed in eight Chinese cities (40,279 adults participated; response rate 75%). There were questions on demographic information of the participants, allergic rhinitis, asthma, perceived odors and home environment. The majority were women (74.7%) and 12.2% were smokers; 6.6% reported allergic rhinitis and 1.6% reported asthma. Totally 38% reported stuffy odor; 24.6% unpleasant odor; 11.5% pungent odor and 10.4% mold odor. Reporting of condensation on window panes were common (62.1%); visible mold or dampness stains (21.9%) and water damage (14.7%) were less common. All dampness indicators were associated with allergic rhinitis and asthma (OR = 1.34–1.87) and all odors (OR = 1.79–6.17). All odors were associated with allergic rhinitis and asthma (OR = 1.23–4.51). Odor perception was partly a mediator of the effects of mold and dampness on allergic rhinitis (% of total effect mediated: 2.7–9.8%) and asthma (2.2–10.7%) when adjusting for other home environment factors. Increased mediation effects for allergic rhinitis (% of total effect mediated: 11.2–17.4%) and asthma (% of total effect mediated: 5.5–14.7%) were found for total odor score (0–8) as compared to the mediation effects for four single odors. In conclusion, mold and dampness in dwellings were associated with adult allergic rhinitis, asthma and odors. Different odors were related to allergic rhinitis and asthma. Some of the effects of mold/dampness on allergic rhinitis and asthma were indirect effect mediated by odors from damp buildings, but most of the effects were direct effects.

A questionnaire survey was performed in eight Chinese cities (40,279 adults participated; response rate 75%). There were questions on demographic information of the participants, allergic rhinitis, asthma, perceived odors and home environment. The majority were women (74.7%) and 12.2% were smokers; 6.6% reported allergic rhinitis and 1.6% reported asthma. Totally 38% reported stuffy odor; 24.6% unpleasant odor; 11.5% pungent odor and 10.4% mold odor. Reporting of condensation on window panes were common (62.1%); visible mold or dampness stains (21.9%) and water damage (14.7%) were less common. All dampness indicators were associated with allergic rhinitis and asthma (OR = 1.34–1.87) and all odors (OR = 1.79–6.17). All odors were associated with allergic rhinitis and asthma (OR = 1.23–4.51). Odor perception was partly a mediator of the effects of mold and dampness on allergic rhinitis (% of total effect mediated: 2.7–9.8%) and asthma (2.2–10.7%) when adjusting for other home environment factors. Increased mediation effects for allergic rhinitis (% of total effect mediated: 11.2–17.4%) and asthma (% of total effect mediated: 5.5–14.7%) were found for total odor score (0–8) as compared to the mediation effects for four single odors. In conclusion, mold and dampness in dwellings were associated with adult allergic rhinitis, asthma and odors. Different odors were related to allergic rhinitis and asthma. Some of the effects of mold/dampness on allergic rhinitis and asthma were indirect effect mediated by odors from damp buildings, but most of the effects were direct effects.

Building envelope dampness exposure is correlated with children's respiratory and allergic diseases. However, little research has compared the variation in the health impact of dampness exposure across multiple cities from a longitudinal perspective. A cross-sectional survey and a repeated one were conducted in children's residences in six cities: Chongqing, Shanghai, Nanjing, Wuhan, Changsha and Taiyuan, China, in 2010 (Phase I) and 2019 (Phase II). We selected 17,810 preschoolers during Phase I and 26,001 preschoolers during Phase II aged 3-6 years without changing residence since birth in the study. The proportion of residences with building envelope dampness exposure and the prevalence of respiratory and allergic diseases, except allergic rhinitis, in preschoolers significantly declined from Phase I to Phase II. Dampness exposure increased the risk for most childhood respiratory diseases in Phase II, with a 34% greater risk of lifetime-ever asthma in early residences and a 36% greater risk of current eczema in current residences. Most diseases showed a significantly positive exposureresponse relationship to the cumulative period of building envelope dampness exposure (p < 0.05). The risk of developing current eczema was approximately 1.35 and 1.73 times higher in children exposed to both early and current dampness in Phase I and Phase II, respectively, than in children who had never been exposed. These findings provide new insights into the respiratory and allergic diseases in Chinese preschoolers because of building envelope dampness exposure over the last decade. The increased risk in Phase II raises concerns about the household's dampness environment.

A questionnaire survey was performed in eight Chinese cities (40,279 adults participated; response rate 75%). There were questions on demographic information of the participants, allergic rhinitis, asthma, perceived odors and home environment. The majority were women (74.7%) and 12.2% were smokers; 6.6% reported allergic rhinitis and 1.6% reported asthma. Totally 38% reported stuffy odor; 24.6% unpleasant odor; 11.5% pungent odor and 10.4% mold odor. Reporting of condensation on window panes were common (62.1%); visible mold or dampness stains (21.9%) and water damage (14.7%) were less common. All dampness indicators were associated with allergic rhinitis and asthma (OR = 1.34–1.87) and all odors (OR = 1.79–6.17). All odors were associated with allergic rhinitis and asthma (OR = 1.23–4.51). Odor perception was partly a mediator of the effects of mold and dampness on allergic rhinitis (% of total effect mediated: 2.7–9.8%) and asthma (2.2–10.7%) when adjusting for other home environment factors. Increased mediation effects for allergic rhinitis (% of total effect mediated: 11.2–17.4%) and asthma (% of total effect mediated: 5.5–14.7%) were found for total odor score (0–8) as compared to the mediation effects for four single odors. In conclusion, mold and dampness in dwellings were associated with adult allergic rhinitis, asthma and odors. Different odors were related to allergic rhinitis and asthma. Some of the effects of mold/dampness on allergic rhinitis and asthma were indirect effect mediated by odors from damp buildings, but most of the effects were direct effects.

A questionnaire survey was performed in eight Chinese cities (40,279 adults participated; response rate 75%). There were questions on demographic information of the participants, allergic rhinitis, asthma, perceived odors and home environment. The majority were women (74.7%) and 12.2% were smokers; 6.6% reported allergic rhinitis and 1.6% reported asthma. Totally 38% reported stuffy odor; 24.6% unpleasant odor; 11.5% pungent odor and 10.4% mold odor. Reporting of condensation on window panes were common (62.1%); visible mold or dampness stains (21.9%) and water damage (14.7%) were less common. All dampness indicators were associated with allergic rhinitis and asthma (OR = 1.34–1.87) and all odors (OR = 1.79–6.17). All odors were associated with allergic rhinitis and asthma (OR = 1.23–4.51). Odor perception was partly a mediator of the effects of mold and dampness on allergic rhinitis (% of total effect mediated: 2.7–9.8%) and asthma (2.2–10.7%) when adjusting for other home environment factors. Increased mediation effects for allergic rhinitis (% of total effect mediated: 11.2–17.4%) and asthma (% of total effect mediated: 5.5–14.7%) were found for total odor score (0–8) as compared to the mediation effects for four single odors. In conclusion, mold and dampness in dwellings were associated with adult allergic rhinitis, asthma and odors. Different odors were related to allergic rhinitis and asthma. Some of the effects of mold/dampness on allergic rhinitis and asthma were indirect effect mediated by odors from damp buildings, but most of the effects were direct effects.

We investigated associations between dampness in Chinese homes and sick building syndrome (SBS) symptoms and studied the role of climate, family size, cleaning and ventilation for dampness, mould and SBS. A questionnaire survey was done in 2019-2020 among adults in five cities (32349 participants) and data on outdoor climate was collected. Multilevel logistic regression was used to calculate adjusted odds ratios (ORs). In total, 2.2% had rhinitis, 1.8% eye, 1.6% throat and 2.9% skin symptoms, 2.1% headache and 8.7% fatigue (weekly symptoms). Overall, 12.1% reported indoor mould, 5.7% damp bedding, 5.3% mould odour and 33.8% humid air in current home. Mould was associated with all symptoms (ORs 1.86-2.15 for minor mold growth and 1.65-3.45 for major mould growth). Damp bedding was associated with all symptoms (ORs 2.18-2.80 for minor dampness and 2.51-8.03 for major dampness). Mould odour was associated with all symptoms (ORs 1.84-2.77 for sometimes odour and ORs 3.78-7.80 for weekly odour). Perception of humid air was associated with all symptoms. ORs increased by number of dampness signs. Precipitation, outdoor relative air humidity and temperature increased dampness, mould and SBS symptoms. Large family size increased dermal symptoms. Daily floor cleaning, airing in winter, putting bedding to sunshine and mechanical ventilation in the bathroom reduced dampness, mould and SBS symptoms. In conclusion, mould and dampness in Chinese homes can increase rhinitis and SBS-symptoms in a dose-response manner. A warmer and more humid climate can increase, and cleaning and ventilation in the home can decrease dampness, mould and SBS symptoms.

We investigated associations between dampness in Chinese homes and sick building syndrome (SBS) symptoms and studied the role of climate, family size, cleaning and ventilation for dampness, mould and SBS. A questionnaire survey was done in 2019-2020 among adults in five cities (32349 participants) and data on outdoor climate was collected. Multilevel logistic regression was used to calculate adjusted odds ratios (ORs). In total, 2.2% had rhinitis, 1.8% eye, 1.6% throat and 2.9% skin symptoms, 2.1% headache and 8.7% fatigue (weekly symptoms). Overall, 12.1% reported indoor mould, 5.7% damp bedding, 5.3% mould odour and 33.8% humid air in current home. Mould was associated with all symptoms (ORs 1.86-2.15 for minor mold growth and 1.65-3.45 for major mould growth). Damp bedding was associated with all symptoms (ORs 2.18-2.80 for minor dampness and 2.51-8.03 for major dampness). Mould odour was associated with all symptoms (ORs 1.84-2.77 for sometimes odour and ORs 3.78-7.80 for weekly odour). Perception of humid air was associated with all symptoms. ORs increased by number of dampness signs. Precipitation, outdoor relative air humidity and temperature increased dampness, mould and SBS symptoms. Large family size increased dermal symptoms. Daily floor cleaning, airing in winter, putting bedding to sunshine and mechanical ventilation in the bathroom reduced dampness, mould and SBS symptoms. In conclusion, mould and dampness in Chinese homes can increase rhinitis and SBS-symptoms in a dose-response manner. A warmer and more humid climate can increase, and cleaning and ventilation in the home can decrease dampness, mould and SBS symptoms.

A questionnaire survey was performed in eight Chinese cities (40,279 adults participated; response rate 75%). There were questions on demographic information of the participants, allergic rhinitis, asthma, perceived odors and home environment. The majority were women (74.7%) and 12.2% were smokers; 6.6% reported allergic rhinitis and 1.6% reported asthma. Totally 38% reported stuffy odor; 24.6% unpleasant odor; 11.5% pungent odor and 10.4% mold odor. Reporting of condensation on window panes were common (62.1%); visible mold or dampness stains (21.9%) and water damage (14.7%) were less common. All dampness indicators were associated with allergic rhinitis and asthma (OR = 1.34–1.87) and all odors (OR = 1.79–6.17). All odors were associated with allergic rhinitis and asthma (OR = 1.23–4.51). Odor perception was partly a mediator of the effects of mold and dampness on allergic rhinitis (% of total effect mediated: 2.7–9.8%) and asthma (2.2–10.7%) when adjusting for other home environment factors. Increased mediation effects for allergic rhinitis (% of total effect mediated: 11.2–17.4%) and asthma (% of total effect mediated: 5.5–14.7%) were found for total odor score (0–8) as compared to the mediation effects for four single odors. In conclusion, mold and dampness in dwellings were associated with adult allergic rhinitis, asthma and odors. Different odors were related to allergic rhinitis and asthma. Some of the effects of mold/dampness on allergic rhinitis and asthma were indirect effect mediated by odors from damp buildings, but most of the effects were direct effects.

Background: Although mounting evidence has associated air pollution and environmental temperature with children's health problems, it is unclear whether there is an interaction between these factors on childhood asthma. Objectives: To explore the effects of temperature-pollution interactions during pre- and post-natal periods on asthma among pre-schoolers. Methods: A retrospective cohort study of 39,782 pre-schoolers was performed during 2010-2012, in seven cities in China. Exposure to three temperature indicators (TI) and three critical ambient air pollutants, including particulate matter with aerodynamic diameter <= 10 mu m (PM10), sulfur dioxide (SO2) and nitrogen dioxide (NO2) as proxies of industrial and vehicular air pollution, was estimated by an inverse distance weighted (IDW) method. Two-level logistical regression analysis was used to examine the association between both pre- and post-natal exposure and childhood asthma in terms of odds ratio (OR) and 95 % confidence interval (CI). Results: Asthma prevalence in pre-schoolers at age of 3-6 years (6.9 %) was significantly associated with traffic-related air pollutant (NO2) exposure, with ORs (95 % CI) of 1.17 (1.06, 1.28), 1.19 (1.05-1.34) and 1.16 (1.03-1.31) for an IQR increase in NO2 exposure during lifetime, pregnancy, and entire postnatal period respectively. Furthermore, childhood asthma was positively associated with exposure to increased temperature during lifetime, pregnancy, and entire postnatal period with ORs (95 % CI) = 1.89 (1.66, 2.16), 1.47 (1.34, 1.61), and 1.15 (1.11, 1.18) respectively, while was negatively associated with decreased temperatures. Childhood asthma was positively related with exposure to extreme heat days (EHD) during postnatal period particularly in first year of life respectively with ORs (95 % CI) = 1.23 (1.04, 1.46) and 1.26 (1.07, 1.47), but was not related with extreme cold days (ECD) exposure. A combination of high air pollutant levels and high temperatures signifi

Background: Low birth weight (LBW), as a major concern in public health, is now increasing worldwide, but its main indoor environmental factors remain unclear.Objective: We examined whether LBW including term-LBW (T-LBW) and preterm-LBW (P-LBW) was associated with maternal exposure to indoor environmental factors, with a purpose to identify the key indoor environmental factor(s) contributing to LBW.Methods: A nationwide retrospective cohort study of 30,735 pre-schoolers in six Chinese cities was performed from 2010 to 2012. One questionnaire survey was conducted to collect information on the pre-schoolers' birth outcomes and their maternal exposure of indoor environmental factors including new furniture, house redecoration, cooking fuels, mould/damp stains, and mouldy odour during pregnancy. Maternal exposure of trafficrelated air pollutant (NO2), industrial pollutant (SO2), and inhalable particulate matter (PM10), as well as meteorological parameters, was estimated in pregnancy. Associations of LBW, T-LBW and P-LBW with indoor environmental factors were evaluated by two-level (city-child) logistic regression models with an odds ratio (OR) and 95% confidence interval (CI).Results: We found that P-LBW (1.0%) and T-LBW (1.4%) prevalence were respectively associated with persistent mould/damp stains and mouldy odour exposure in utero, ORs = 1.81 (95% CI: 1.01-3.24) and 1.49 (95% CI: 1.01-2.21). Exposure to high temperature and PM2.5 in pregnancy significantly enhanced the effect of persistent mould/damp stains and/or mouldy odour on P-LBW and LBW, ORs (95% CI) = 2.92 (1.40-6.07) and 1.78 (1.00-3.15) with significant interaction p values of 0.067 and 0.094 respectively. Sensitivity analysis suggested that raising cats and dogs significantly increased LBW risk of persistent mould/damp stains and mouldy odour exposure.

Common cold is usually considered to be associated with outdoor climate, but the evidence linking with indoor environmental factors is lacking. The role of indoor renovations during which critical timing window on childhood common cold remains unclear. Therefore, we investigated the effect of exposure to new furniture and/or redecoration during prenatal and postnatal periods on the occurrence and duration of common cold in preschool children. We conducted a retrospective cohort study of 39 782 children aged 3-6 years in seven cities of China. The occurrence and duration of common cold in children, and their lifetime exposures to indoor new furniture and redecoration (including pregnancy, the first year of life, and after one year old) were assessed using a questionnaire administered by the parents. Associations between high frequency (>5 colds) and long duration (>= 2 weeks per cold) of common cold during past 12 months and exposure to indoor new furniture/redecoration were examined by logistic regression models in terms of odds ratio (OR) and 95% confidence interval (CI). We found that the prevalence of high frequency and long duration of common cold in preschool children in China were, respectively, 9.2% and 11.9%. Frequent common cold was significantly associated with exposure to indoor new furniture/redecoration during pregnancy, first year, and after 1 year old, respectively, with the ORs (95% CI) = 1.25 (1.12-1.39), 1.11 (1.00-1.25), and 1.09 (1.01-1.18). Furthermore, childhood long duration per cold was associated with exposure to indoor new furniture/redecoration during pregnancy with OR (95% CI) of 1.14 (1.03-1.25) but not with postnatal exposure. We identified that prenatal exposure to home renovation was more critical than postnatal exposure for an increased risk of high frequency and long duration of common cold. Sensitivity analysis showed that the association between prenatal exposure to indoor renovations and the risk of childhood common cold wa

Background: Although mounting evidence has associated air pollution and environmental temperature with children's health problems, it is unclear whether there is an interaction between these factors on childhood asthma. Objectives: To explore the effects of temperature-pollution interactions during pre- and post-natal periods on asthma among pre-schoolers. Methods: A retrospective cohort study of 39,782 pre-schoolers was performed during 2010-2012, in seven cities in China. Exposure to three temperature indicators (TI) and three critical ambient air pollutants, including particulate matter with aerodynamic diameter <= 10 mu m (PM10), sulfur dioxide (SO2) and nitrogen dioxide (NO2) as proxies of industrial and vehicular air pollution, was estimated by an inverse distance weighted (IDW) method. Two-level logistical regression analysis was used to examine the association between both pre- and post-natal exposure and childhood asthma in terms of odds ratio (OR) and 95 % confidence interval (CI). Results: Asthma prevalence in pre-schoolers at age of 3-6 years (6.9 %) was significantly associated with traffic-related air pollutant (NO2) exposure, with ORs (95 % CI) of 1.17 (1.06, 1.28), 1.19 (1.05-1.34) and 1.16 (1.03-1.31) for an IQR increase in NO2 exposure during lifetime, pregnancy, and entire postnatal period respectively. Furthermore, childhood asthma was positively associated with exposure to increased temperature during lifetime, pregnancy, and entire postnatal period with ORs (95 % CI) = 1.89 (1.66, 2.16), 1.47 (1.34, 1.61), and 1.15 (1.11, 1.18) respectively, while was negatively associated with decreased temperatures. Childhood asthma was positively related with exposure to extreme heat days (EHD) during postnatal period particularly in first year of life respectively with ORs (95 % CI) = 1.23 (1.04, 1.46) and 1.26 (1.07, 1.47), but was not related with extreme cold days (ECD) exposure. A combination of high air pollutant levels and high temperatures signifi

Background: Although mounting evidence has associated air pollution and environmental temperature with children's health problems, it is unclear whether there is an interaction between these factors on childhood asthma. Objectives: To explore the effects of temperature-pollution interactions during pre- and post-natal periods on asthma among pre-schoolers. Methods: A retrospective cohort study of 39,782 pre-schoolers was performed during 2010-2012, in seven cities in China. Exposure to three temperature indicators (TI) and three critical ambient air pollutants, including particulate matter with aerodynamic diameter <= 10 mu m (PM10), sulfur dioxide (SO2) and nitrogen dioxide (NO2) as proxies of industrial and vehicular air pollution, was estimated by an inverse distance weighted (IDW) method. Two-level logistical regression analysis was used to examine the association between both pre- and post-natal exposure and childhood asthma in terms of odds ratio (OR) and 95 % confidence interval (CI). Results: Asthma prevalence in pre-schoolers at age of 3-6 years (6.9 %) was significantly associated with traffic-related air pollutant (NO2) exposure, with ORs (95 % CI) of 1.17 (1.06, 1.28), 1.19 (1.05-1.34) and 1.16 (1.03-1.31) for an IQR increase in NO2 exposure during lifetime, pregnancy, and entire postnatal period respectively. Furthermore, childhood asthma was positively associated with exposure to increased temperature during lifetime, pregnancy, and entire postnatal period with ORs (95 % CI) = 1.89 (1.66, 2.16), 1.47 (1.34, 1.61), and 1.15 (1.11, 1.18) respectively, while was negatively associated with decreased temperatures. Childhood asthma was positively related with exposure to extreme heat days (EHD) during postnatal period particularly in first year of life respectively with ORs (95 % CI) = 1.23 (1.04, 1.46) and 1.26 (1.07, 1.47), but was not related with extreme cold days (ECD) exposure. A combination of high air pollutant levels and high temperatures signifi

A questionnaire survey on dermal symptoms and home environment was performed in eight Chinese cities (40 279 participants). Data on city level temperature, precipitation, PM10 , NO2, and gross domestic product (GDP) per capita were collected. In total, 2.2% had eczema, 2.4% facial erythema (FE) and 2.6% seborrheic dermatitis symptoms (SD). Higher temperature was associated with eczema (OR = 1.09). Higher GDP per capita was related to less SD. Higher PM10 was related to SD. Suburban living was protective for eczema (OR = 0.77) (vs. urban). Living in old buildings (built before 1991) was related to eczema (OR = 1.42). Living near heavily trafficked roads was related to FE (OR = 1.33) and SD (OR = 1.35). Having new furniture was related to all symptoms (OR = 1.26-1.47). Burning mosquito coils (OR = 1.37-1.57) and incense (OR = 1.33-1.37) were associated with eczema, FE, or SD. Presence of cockroaches and rats/mice was associated with FE or SD (OR = 1.31-1.40). Using air conditioner, daily cleaning and frequently exposing bedding to sunshine were protective (OR = 0.60-0.83). In conclusion, higher temperature, higher PM10 , urban living, living near heavily trafficked roads, old buildings, new furniture, burning mosquito coils and incense, and presence of cockroaches/rats/mice increased the risk of eczema, FE, or SD. Higher GDP, air conditioner, daily cleaning, and exposing bedding to sunshine were protective.

Background: Although mounting evidence has associated air pollution and environmental temperature with children's health problems, it is unclear whether there is an interaction between these factors on childhood asthma. Objectives: To explore the effects of temperature-pollution interactions during pre- and post-natal periods on asthma among pre-schoolers. Methods: A retrospective cohort study of 39,782 pre-schoolers was performed during 2010-2012, in seven cities in China. Exposure to three temperature indicators (TI) and three critical ambient air pollutants, including particulate matter with aerodynamic diameter <= 10 mu m (PM10), sulfur dioxide (SO2) and nitrogen dioxide (NO2) as proxies of industrial and vehicular air pollution, was estimated by an inverse distance weighted (IDW) method. Two-level logistical regression analysis was used to examine the association between both pre- and post-natal exposure and childhood asthma in terms of odds ratio (OR) and 95 % confidence interval (CI). Results: Asthma prevalence in pre-schoolers at age of 3-6 years (6.9 %) was significantly associated with traffic-related air pollutant (NO2) exposure, with ORs (95 % CI) of 1.17 (1.06, 1.28), 1.19 (1.05-1.34) and 1.16 (1.03-1.31) for an IQR increase in NO2 exposure during lifetime, pregnancy, and entire postnatal period respectively. Furthermore, childhood asthma was positively associated with exposure to increased temperature during lifetime, pregnancy, and entire postnatal period with ORs (95 % CI) = 1.89 (1.66, 2.16), 1.47 (1.34, 1.61), and 1.15 (1.11, 1.18) respectively, while was negatively associated with decreased temperatures. Childhood asthma was positively related with exposure to extreme heat days (EHD) during postnatal period particularly in first year of life respectively with ORs (95 % CI) = 1.23 (1.04, 1.46) and 1.26 (1.07, 1.47), but was not related with extreme cold days (ECD) exposure. A combination of high air pollutant levels and high temperatures signifi

Background: Although mounting evidence has associated air pollution and environmental temperature with children's health problems, it is unclear whether there is an interaction between these factors on childhood asthma. Objectives: To explore the effects of temperature-pollution interactions during pre- and post-natal periods on asthma among pre-schoolers. Methods: A retrospective cohort study of 39,782 pre-schoolers was performed during 2010-2012, in seven cities in China. Exposure to three temperature indicators (TI) and three critical ambient air pollutants, including particulate matter with aerodynamic diameter <= 10 mu m (PM10), sulfur dioxide (SO2) and nitrogen dioxide (NO2) as proxies of industrial and vehicular air pollution, was estimated by an inverse distance weighted (IDW) method. Two-level logistical regression analysis was used to examine the association between both pre- and post-natal exposure and childhood asthma in terms of odds ratio (OR) and 95 % confidence interval (CI). Results: Asthma prevalence in pre-schoolers at age of 3-6 years (6.9 %) was significantly associated with traffic-related air pollutant (NO2) exposure, with ORs (95 % CI) of 1.17 (1.06, 1.28), 1.19 (1.05-1.34) and 1.16 (1.03-1.31) for an IQR increase in NO2 exposure during lifetime, pregnancy, and entire postnatal period respectively. Furthermore, childhood asthma was positively associated with exposure to increased temperature during lifetime, pregnancy, and entire postnatal period with ORs (95 % CI) = 1.89 (1.66, 2.16), 1.47 (1.34, 1.61), and 1.15 (1.11, 1.18) respectively, while was negatively associated with decreased temperatures. Childhood asthma was positively related with exposure to extreme heat days (EHD) during postnatal period particularly in first year of life respectively with ORs (95 % CI) = 1.23 (1.04, 1.46) and 1.26 (1.07, 1.47), but was not related with extreme cold days (ECD) exposure. A combination of high air pollutant levels and high temperatures signifi

We investigated associations between prenatal and postnatal environmental factors and onset and remission of preschool childhood eczema across China. The study population was preschoolers in randomized day care centers in seven cities (N = 39,782). Data on eczema and prenatal and postnatal indoor and outdoor environment were obtained from a cross-sectional questionnaire sent to parents or other guardians. Reports on eczema in the first 2 years and in the past year was used to retrospectively calculate onset and remission (changes of reported eczema). Prenatal and postnatal outdoor temperature, NO2 and PM10 were modelled from official air pollution data. Associations were estimated by two-level logistic regression. Calculated onset rate was 3.2%/y and remission rate 29.2%/y. Exposure to NO2 during pregnancy was associated with onset of eczema, similarly for all trimesters. Postnatal PM10 and NO2 were related to decreased remission. Postnatal outdoor temperature was associated with onset of eczema. Pre-natal and current redecoration or buying new furniture, and perinatal as well as current dampness and indoor mould, were associated with increased onset and decreased remission. Cockroaches in current home was another indoor risk factors. Prenatal exposure to farm environment and large family size were all negatively associated with eczema. In conclusion, a warmer climate and prenatal NO2 can be associated with increased onset of eczema in Chinese preschoolers. Postnatal PM10 and NO2 can be associated with reduced remission. Perinatal and current dampness, indoor mould and cockroaches may increase onset and decrease remission. Exposure to chemical emissions from indoor materials after first year of life may increase onset. Prenatal exposure to farm environment and large family size could be protective.

The long-term effects of ambient PM2.5 and chemical constituents on childhood pneumonia were still unknown. A cross-sectional study was conducted in 30,315 children in the China Children, Homes, Health (CCHH) project, involving 205 preschools in six cities in China, to investigate the long-term effects of PM2.5 constituents on lifetime-ever diagnosed pneumonia. Information on the lifetime-ever pneumonia and demographics were collected by validated questionnaires. The lifetime annual average ambient PM2.5, ozone and five main PM2.5 constituents, including SO42-, NO3-, NH4+, organic matter (OM) and black carbon (BC), were estimated according to preschool addresses by a combination of satellite remote sensing, chemical transport modeling and ground-based monitors. The prevalence of lifetime-ever diagnosed pneumonia was 34.5% across six cities and differed significantly among cities (p = 0.004). The two-level logistic regression models showed that the adjusted odds ratio for PM2.5 (per 10 µg/m3) and its constituents (per 1 µg/m3)-SO42-, NO3-, NH4+, and OM were 1.12 (95% CI:1.07-1.18), 1.02 (1.00-1.04), 1.06 (1.04-1.09), 1.05 (1.03-1.07) and 1.09 (1.06-1.12), respectively. Children in urban area, aged < 5 years and breastfeeding time < 6 months enhanced the risks of pneumonia. Our study provided robust results that long-term levels of ambient PM2.5 and its constituents increased the risk of childhood pneumonia, especially NH4+, NO3- and OM.

The long-term effects of ambient PM2.5 and chemical constituents on childhood pneumonia were still unknown. A cross-sectional study was conducted in 30,315 children in the China Children, Homes, Health (CCHH) project, involving 205 preschools in six cities in China, to investigate the long-term effects of PM2.5 constituents on lifetime-ever diagnosed pneumonia. Information on the lifetime-ever pneumonia and demographics were collected by validated questionnaires. The lifetime annual average ambient PM2.5, ozone and five main PM2.5 constituents, including SO42-, NO3-, NH4+, organic matter (OM) and black carbon (BC), were estimated according to preschool addresses by a combination of satellite remote sensing, chemical transport modeling and ground-based monitors. The prevalence of lifetime-ever diagnosed pneumonia was 34.5% across six cities and differed significantly among cities (p = 0.004). The two-level logistic regression models showed that the adjusted odds ratio for PM2.5 (per 10 µg/m3) and its constituents (per 1 µg/m3)-SO42-, NO3-, NH4+, and OM were 1.12 (95% CI:1.07-1.18), 1.02 (1.00-1.04), 1.06 (1.04-1.09), 1.05 (1.03-1.07) and 1.09 (1.06-1.12), respectively. Children in urban area, aged < 5 years and breastfeeding time < 6 months enhanced the risks of pneumonia. Our study provided robust results that long-term levels of ambient PM2.5 and its constituents increased the risk of childhood pneumonia, especially NH4+, NO3- and OM.

The long-term effects of ambient PM2.5 and chemical constituents on childhood pneumonia were still unknown. A cross-sectional study was conducted in 30,315 children in the China Children, Homes, Health (CCHH) project, involving 205 preschools in six cities in China, to investigate the long-term effects of PM2.5 constituents on lifetime-ever diagnosed pneumonia. Information on the lifetime-ever pneumonia and demographics were collected by validated questionnaires. The lifetime annual average ambient PM2.5, ozone and five main PM2.5 constituents, including SO42-, NO3-, NH4+, organic matter (OM) and black carbon (BC), were estimated according to preschool addresses by a combination of satellite remote sensing, chemical transport modeling and ground-based monitors. The prevalence of lifetime-ever diagnosed pneumonia was 34.5% across six cities and differed significantly among cities (p = 0.004). The two-level logistic regression models showed that the adjusted odds ratio for PM2.5 (per 10 µg/m3) and its constituents (per 1 µg/m3)-SO42-, NO3-, NH4+, and OM were 1.12 (95% CI:1.07-1.18), 1.02 (1.00-1.04), 1.06 (1.04-1.09), 1.05 (1.03-1.07) and 1.09 (1.06-1.12), respectively. Children in urban area, aged < 5 years and breastfeeding time < 6 months enhanced the risks of pneumonia. Our study provided robust results that long-term levels of ambient PM2.5 and its constituents increased the risk of childhood pneumonia, especially NH4+, NO3- and OM.

We estimated associations between ambient air pollution, home environment and asthma as well as rhinitis among adults across China. A total of 40,279 young adults from eight Chinese cities participated in a questionnaire survey (participation rate 75%). There were questions on health and home environment. Information on city level gross domestic product (GDP) per capita, ambient temperature and PM10 and NO2 were collected from registers. Two-level logistic regression models were used to study health associations. Totally 1.6% reported asthma and 6.6% reported allergic rhinitis (AR). Higher temperature was associated with more asthma but less AR. Higher GDP was associated with less asthma but more AR. Higher degree of urbanization, higher level of NO2 and living near heavily trafficked road were risk factors for asthma and AR. Participants in older buildings reported more asthma. Redecoration and buying new furniture were related to more asthma and AR (OR = 1.15-1.91). Using natural gas (OR = 1.34) and biomass (OR = 1.35) for cooking were risk factors for AR. Burning mosquito coils and incense increased the risk of asthma and AR. Cat keeping (OR = 2.88), dog keeping (OR = 2.04), cockroaches (OR = 1.54) and rats or mice (OR = 1.46) were associated with asthma. Cockroaches increased the risk of AR (OR = 1.22). Air humidifier and air cleaner were linked to asthma and AR. Frequent cleaning and exposing bedding to sunshine were protective. In conclusion, urbanization, NO2 and traffic exhaust can increase the risk of adult asthma and AR. Higher ambient temperature was related to more asthma but less AR. Indoor animals such as cats, dogs, rats/mice and presence of cockroaches were associated with asthma or AR. Indoor chemical sources such as redecoration and new furniture were other risk factors. Cooking with natural gas or biomass and burning mosquito coils and incense were associated with asthma or AR. Frequent cleaning and exposing bedding to sunshine were protective.

We investigated associations between prenatal and postnatal environmental factors and onset and remission of preschool childhood eczema across China. The study population was preschoolers in randomized day care centers in seven cities (N = 39,782). Data on eczema and prenatal and postnatal indoor and outdoor environment were obtained from a cross-sectional questionnaire sent to parents or other guardians. Reports on eczema in the first 2 years and in the past year was used to retrospectively calculate onset and remission (changes of reported eczema). Prenatal and postnatal outdoor temperature, NO2 and PM10 were modelled from official air pollution data. Associations were estimated by two-level logistic regression. Calculated onset rate was 3.2%/y and remission rate 29.2%/y. Exposure to NO2 during pregnancy was associated with onset of eczema, similarly for all trimesters. Postnatal PM10 and NO2 were related to decreased remission. Postnatal outdoor temperature was associated with onset of eczema. Pre-natal and current redecoration or buying new furniture, and perinatal as well as current dampness and indoor mould, were associated with increased onset and decreased remission. Cockroaches in current home was another indoor risk factors. Prenatal exposure to farm environment and large family size were all negatively associated with eczema. In conclusion, a warmer climate and prenatal NO2 can be associated with increased onset of eczema in Chinese preschoolers. Postnatal PM10 and NO2 can be associated with reduced remission. Perinatal and current dampness, indoor mould and cockroaches may increase onset and decrease remission. Exposure to chemical emissions from indoor materials after first year of life may increase onset. Prenatal exposure to farm environment and large family size could be protective.

We estimated associations between ambient air pollution, home environment and asthma as well as rhinitis among adults across China. A total of 40,279 young adults from eight Chinese cities participated in a questionnaire survey (participation rate 75%). There were questions on health and home environment. Information on city level gross domestic product (GDP) per capita, ambient temperature and PM10 and NO2 were collected from registers. Two-level logistic regression models were used to study health associations. Totally 1.6% reported asthma and 6.6% reported allergic rhinitis (AR). Higher temperature was associated with more asthma but less AR. Higher GDP was associated with less asthma but more AR. Higher degree of urbanization, higher level of NO2 and living near heavily trafficked road were risk factors for asthma and AR. Participants in older buildings reported more asthma. Redecoration and buying new furniture were related to more asthma and AR (OR = 1.15-1.91). Using natural gas (OR = 1.34) and biomass (OR = 1.35) for cooking were risk factors for AR. Burning mosquito coils and incense increased the risk of asthma and AR. Cat keeping (OR = 2.88), dog keeping (OR = 2.04), cockroaches (OR = 1.54) and rats or mice (OR = 1.46) were associated with asthma. Cockroaches increased the risk of AR (OR = 1.22). Air humidifier and air cleaner were linked to asthma and AR. Frequent cleaning and exposing bedding to sunshine were protective. In conclusion, urbanization, NO2 and traffic exhaust can increase the risk of adult asthma and AR. Higher ambient temperature was related to more asthma but less AR. Indoor animals such as cats, dogs, rats/mice and presence of cockroaches were associated with asthma or AR. Indoor chemical sources such as redecoration and new furniture were other risk factors. Cooking with natural gas or biomass and burning mosquito coils and incense were associated with asthma or AR. Frequent cleaning and exposing bedding to sunshine were protective.

We estimated associations between ambient air pollution, home environment and asthma as well as rhinitis among adults across China. A total of 40,279 young adults from eight Chinese cities participated in a questionnaire survey (participation rate 75%). There were questions on health and home environment. Information on city level gross domestic product (GDP) per capita, ambient temperature and PM10 and NO2 were collected from registers. Two-level logistic regression models were used to study health associations. Totally 1.6% reported asthma and 6.6% reported allergic rhinitis (AR). Higher temperature was associated with more asthma but less AR. Higher GDP was associated with less asthma but more AR. Higher degree of urbanization, higher level of NO2 and living near heavily trafficked road were risk factors for asthma and AR. Participants in older buildings reported more asthma. Redecoration and buying new furniture were related to more asthma and AR (OR = 1.15-1.91). Using natural gas (OR = 1.34) and biomass (OR = 1.35) for cooking were risk factors for AR. Burning mosquito coils and incense increased the risk of asthma and AR. Cat keeping (OR = 2.88), dog keeping (OR = 2.04), cockroaches (OR = 1.54) and rats or mice (OR = 1.46) were associated with asthma. Cockroaches increased the risk of AR (OR = 1.22). Air humidifier and air cleaner were linked to asthma and AR. Frequent cleaning and exposing bedding to sunshine were protective. In conclusion, urbanization, NO2 and traffic exhaust can increase the risk of adult asthma and AR. Higher ambient temperature was related to more asthma but less AR. Indoor animals such as cats, dogs, rats/mice and presence of cockroaches were associated with asthma or AR. Indoor chemical sources such as redecoration and new furniture were other risk factors. Cooking with natural gas or biomass and burning mosquito coils and incense were associated with asthma or AR. Frequent cleaning and exposing bedding to sunshine were protective.

We investigated associations between prenatal and postnatal environmental factors and onset and remission of preschool childhood eczema across China. The study population was preschoolers in randomized day care centers in seven cities (N = 39,782). Data on eczema and prenatal and postnatal indoor and outdoor environment were obtained from a cross-sectional questionnaire sent to parents or other guardians. Reports on eczema in the first 2 years and in the past year was used to retrospectively calculate onset and remission (changes of reported eczema). Prenatal and postnatal outdoor temperature, NO2 and PM10 were modelled from official air pollution data. Associations were estimated by two-level logistic regression. Calculated onset rate was 3.2%/y and remission rate 29.2%/y. Exposure to NO2 during pregnancy was associated with onset of eczema, similarly for all trimesters. Postnatal PM10 and NO2 were related to decreased remission. Postnatal outdoor temperature was associated with onset of eczema. Pre-natal and current redecoration or buying new furniture, and perinatal as well as current dampness and indoor mould, were associated with increased onset and decreased remission. Cockroaches in current home was another indoor risk factors. Prenatal exposure to farm environment and large family size were all negatively associated with eczema. In conclusion, a warmer climate and prenatal NO2 can be associated with increased onset of eczema in Chinese preschoolers. Postnatal PM10 and NO2 can be associated with reduced remission. Perinatal and current dampness, indoor mould and cockroaches may increase onset and decrease remission. Exposure to chemical emissions from indoor materials after first year of life may increase onset. Prenatal exposure to farm environment and large family size could be protective.

The long-term effects of ambient PM2.5 and chemical constituents on childhood pneumonia were still unknown. A cross-sectional study was conducted in 30,315 children in the China Children, Homes, Health (CCHH) project, involving 205 preschools in six cities in China, to investigate the long-term effects of PM2.5 constituents on lifetime-ever diagnosed pneumonia. Information on the lifetime-ever pneumonia and demographics were collected by validated questionnaires. The lifetime annual average ambient PM2.5, ozone and five main PM2.5 constituents, including SO42-, NO3-, NH4+, organic matter (OM) and black carbon (BC), were estimated according to preschool addresses by a combination of satellite remote sensing, chemical transport modeling and ground-based monitors. The prevalence of lifetime-ever diagnosed pneumonia was 34.5% across six cities and differed significantly among cities (p = 0.004). The two-level logistic regression models showed that the adjusted odds ratio for PM2.5 (per 10 µg/m3) and its constituents (per 1 µg/m3)-SO42-, NO3-, NH4+, and OM were 1.12 (95% CI:1.07-1.18), 1.02 (1.00-1.04), 1.06 (1.04-1.09), 1.05 (1.03-1.07) and 1.09 (1.06-1.12), respectively. Children in urban area, aged < 5 years and breastfeeding time < 6 months enhanced the risks of pneumonia. Our study provided robust results that long-term levels of ambient PM2.5 and its constituents increased the risk of childhood pneumonia, especially NH4+, NO3- and OM.

We estimated associations between ambient air pollution, home environment and asthma as well as rhinitis among adults across China. A total of 40,279 young adults from eight Chinese cities participated in a questionnaire survey (participation rate 75%). There were questions on health and home environment. Information on city level gross domestic product (GDP) per capita, ambient temperature and PM10 and NO2 were collected from registers. Two-level logistic regression models were used to study health associations. Totally 1.6% reported asthma and 6.6% reported allergic rhinitis (AR). Higher temperature was associated with more asthma but less AR. Higher GDP was associated with less asthma but more AR. Higher degree of urbanization, higher level of NO2 and living near heavily trafficked road were risk factors for asthma and AR. Participants in older buildings reported more asthma. Redecoration and buying new furniture were related to more asthma and AR (OR = 1.15-1.91). Using natural gas (OR = 1.34) and biomass (OR = 1.35) for cooking were risk factors for AR. Burning mosquito coils and incense increased the risk of asthma and AR. Cat keeping (OR = 2.88), dog keeping (OR = 2.04), cockroaches (OR = 1.54) and rats or mice (OR = 1.46) were associated with asthma. Cockroaches increased the risk of AR (OR = 1.22). Air humidifier and air cleaner were linked to asthma and AR. Frequent cleaning and exposing bedding to sunshine were protective. In conclusion, urbanization, NO2 and traffic exhaust can increase the risk of adult asthma and AR. Higher ambient temperature was related to more asthma but less AR. Indoor animals such as cats, dogs, rats/mice and presence of cockroaches were associated with asthma or AR. Indoor chemical sources such as redecoration and new furniture were other risk factors. Cooking with natural gas or biomass and burning mosquito coils and incense were associated with asthma or AR. Frequent cleaning and exposing bedding to sunshine were protective.

We investigated associations between prenatal and postnatal environmental factors and onset and remission of preschool childhood eczema across China. The study population was preschoolers in randomized day care centers in seven cities (N = 39,782). Data on eczema and prenatal and postnatal indoor and outdoor environment were obtained from a cross-sectional questionnaire sent to parents or other guardians. Reports on eczema in the first 2 years and in the past year was used to retrospectively calculate onset and remission (changes of reported eczema). Prenatal and postnatal outdoor temperature, NO2 and PM10 were modelled from official air pollution data. Associations were estimated by two-level logistic regression. Calculated onset rate was 3.2%/y and remission rate 29.2%/y. Exposure to NO2 during pregnancy was associated with onset of eczema, similarly for all trimesters. Postnatal PM10 and NO2 were related to decreased remission. Postnatal outdoor temperature was associated with onset of eczema. Pre-natal and current redecoration or buying new furniture, and perinatal as well as current dampness and indoor mould, were associated with increased onset and decreased remission. Cockroaches in current home was another indoor risk factors. Prenatal exposure to farm environment and large family size were all negatively associated with eczema. In conclusion, a warmer climate and prenatal NO2 can be associated with increased onset of eczema in Chinese preschoolers. Postnatal PM10 and NO2 can be associated with reduced remission. Perinatal and current dampness, indoor mould and cockroaches may increase onset and decrease remission. Exposure to chemical emissions from indoor materials after first year of life may increase onset. Prenatal exposure to farm environment and large family size could be protective.

A critical review of the current state of knowledge of chemical emissions from indoor sources, partitioning among indoor compartments, and the ensuing indoor exposure leads to a proposal for a modular mechanistic framework for predicting human exposure to semivolatile organic compounds (SVOCs). Mechanistically consistent source emission categories include solid, soft, frequent contact, applied, sprayed, and high temperature sources. Environmental compartments are the gas phase, airborne particles, settled dust, indoor surfaces, and clothing. Identified research needs are the development of dynamic emission models for several of the source emission categories and of estimation strategies for critical model parameters. The modular structure of the framework facilitates subsequent inclusion of new knowledge, other chemical classes of indoor pollutants, and additional mechanistic processes relevant to human exposure indoors. The framework may serve as the foundation for developing an open-source community model to better support collaborative research and improve access for application by stakeholders. Combining exposure estimates derived using this framework with toxicity data for different end points and toxicokinetic mechanisms will accelerate chemical risk prioritization, advance effective chemical management decisions, and protect public health.

The long-term effects of ambient PM2.5 and chemical constituents on childhood pneumonia were still unknown. A cross-sectional study was conducted in 30,315 children in the China Children, Homes, Health (CCHH) project, involving 205 preschools in six cities in China, to investigate the long-term effects of PM2.5 constituents on lifetime-ever diagnosed pneumonia. Information on the lifetime-ever pneumonia and demographics were collected by validated questionnaires. The lifetime annual average ambient PM2.5, ozone and five main PM2.5 constituents, including SO42-, NO3-, NH4+, organic matter (OM) and black carbon (BC), were estimated according to preschool addresses by a combination of satellite remote sensing, chemical transport modeling and ground-based monitors. The prevalence of lifetime-ever diagnosed pneumonia was 34.5% across six cities and differed significantly among cities (p = 0.004). The two-level logistic regression models showed that the adjusted odds ratio for PM2.5 (per 10 µg/m3) and its constituents (per 1 µg/m3)-SO42-, NO3-, NH4+, and OM were 1.12 (95% CI:1.07-1.18), 1.02 (1.00-1.04), 1.06 (1.04-1.09), 1.05 (1.03-1.07) and 1.09 (1.06-1.12), respectively. Children in urban area, aged < 5 years and breastfeeding time < 6 months enhanced the risks of pneumonia. Our study provided robust results that long-term levels of ambient PM2.5 and its constituents increased the risk of childhood pneumonia, especially NH4+, NO3- and OM.

We investigated associations between prenatal and postnatal environmental factors and onset and remission of preschool childhood eczema across China. The study population was preschoolers in randomized day care centers in seven cities (N = 39,782). Data on eczema and prenatal and postnatal indoor and outdoor environment were obtained from a cross-sectional questionnaire sent to parents or other guardians. Reports on eczema in the first 2 years and in the past year was used to retrospectively calculate onset and remission (changes of reported eczema). Prenatal and postnatal outdoor temperature, NO2 and PM10 were modelled from official air pollution data. Associations were estimated by two-level logistic regression. Calculated onset rate was 3.2%/y and remission rate 29.2%/y. Exposure to NO2 during pregnancy was associated with onset of eczema, similarly for all trimesters. Postnatal PM10 and NO2 were related to decreased remission. Postnatal outdoor temperature was associated with onset of eczema. Pre-natal and current redecoration or buying new furniture, and perinatal as well as current dampness and indoor mould, were associated with increased onset and decreased remission. Cockroaches in current home was another indoor risk factors. Prenatal exposure to farm environment and large family size were all negatively associated with eczema. In conclusion, a warmer climate and prenatal NO2 can be associated with increased onset of eczema in Chinese preschoolers. Postnatal PM10 and NO2 can be associated with reduced remission. Perinatal and current dampness, indoor mould and cockroaches may increase onset and decrease remission. Exposure to chemical emissions from indoor materials after first year of life may increase onset. Prenatal exposure to farm environment and large family size could be protective.

We estimated associations between ambient air pollution, home environment and asthma as well as rhinitis among adults across China. A total of 40,279 young adults from eight Chinese cities participated in a questionnaire survey (participation rate 75%). There were questions on health and home environment. Information on city level gross domestic product (GDP) per capita, ambient temperature and PM10 and NO2 were collected from registers. Two-level logistic regression models were used to study health associations. Totally 1.6% reported asthma and 6.6% reported allergic rhinitis (AR). Higher temperature was associated with more asthma but less AR. Higher GDP was associated with less asthma but more AR. Higher degree of urbanization, higher level of NO2 and living near heavily trafficked road were risk factors for asthma and AR. Participants in older buildings reported more asthma. Redecoration and buying new furniture were related to more asthma and AR (OR = 1.15-1.91). Using natural gas (OR = 1.34) and biomass (OR = 1.35) for cooking were risk factors for AR. Burning mosquito coils and incense increased the risk of asthma and AR. Cat keeping (OR = 2.88), dog keeping (OR = 2.04), cockroaches (OR = 1.54) and rats or mice (OR = 1.46) were associated with asthma. Cockroaches increased the risk of AR (OR = 1.22). Air humidifier and air cleaner were linked to asthma and AR. Frequent cleaning and exposing bedding to sunshine were protective. In conclusion, urbanization, NO2 and traffic exhaust can increase the risk of adult asthma and AR. Higher ambient temperature was related to more asthma but less AR. Indoor animals such as cats, dogs, rats/mice and presence of cockroaches were associated with asthma or AR. Indoor chemical sources such as redecoration and new furniture were other risk factors. Cooking with natural gas or biomass and burning mosquito coils and incense were associated with asthma or AR. Frequent cleaning and exposing bedding to sunshine were protective.

Airborne particulate matters (PM) pose serious health threats to the population, and efficient filtration is needed for indoor and vehicular environments. However, there is an intrinsic conflict between filtration efficiency, air resistance, and service life. In this study, a two-stage electrostatically assisted air (EAA) filtration device is designed and the efficiency-air resistance-filter life envelope is significantly improved by a thin coating of polydopamine (PDA) on the polyethylene terephthalate (PET) coarse filter by in situ dopamine polymerization. The 8 mm thick EAA PDA-140@PET filter has a high filtration efficiency of 99.48% for 0.3 µm particles, low air resistance of 9.5 Pa at a filtration velocity of 0.4 m s-1 , and steady performance up to 30 d. Compared with the bare PET filter, the penetration rate for 0.3 µm particles is lowered by 20×. The coated PDA is of submicron thickness, 10-3 × the gap distance between filter fibers, so low air resistance could be maintained. The filter shows steadily high filtration efficiency and an acceptable increase of air resistance and holds nearly as many particles as its own weight in a 30 day long-term test. The working mechanism of the EAA coarse filter is investigated, and the materials design criteria are proposed.

A critical review of the current state of knowledge of chemical emissions from indoor sources, partitioning among indoor compartments, and the ensuing indoor exposure leads to a proposal for a modular mechanistic framework for predicting human exposure to semivolatile organic compounds (SVOCs). Mechanistically consistent source emission categories include solid, soft, frequent contact, applied, sprayed, and high temperature sources. Environmental compartments are the gas phase, airborne particles, settled dust, indoor surfaces, and clothing. Identified research needs are the development of dynamic emission models for several of the source emission categories and of estimation strategies for critical model parameters. The modular structure of the framework facilitates subsequent inclusion of new knowledge, other chemical classes of indoor pollutants, and additional mechanistic processes relevant to human exposure indoors. The framework may serve as the foundation for developing an open-source community model to better support collaborative research and improve access for application by stakeholders. Combining exposure estimates derived using this framework with toxicity data for different end points and toxicokinetic mechanisms will accelerate chemical risk prioritization, advance effective chemical management decisions, and protect public health.

We estimated associations between ambient air pollution, home environment and asthma as well as rhinitis among adults across China. A total of 40,279 young adults from eight Chinese cities participated in a questionnaire survey (participation rate 75%). There were questions on health and home environment. Information on city level gross domestic product (GDP) per capita, ambient temperature and PM10 and NO2 were collected from registers. Two-level logistic regression models were used to study health associations. Totally 1.6% reported asthma and 6.6% reported allergic rhinitis (AR). Higher temperature was associated with more asthma but less AR. Higher GDP was associated with less asthma but more AR. Higher degree of urbanization, higher level of NO2 and living near heavily trafficked road were risk factors for asthma and AR. Participants in older buildings reported more asthma. Redecoration and buying new furniture were related to more asthma and AR (OR = 1.15-1.91). Using natural gas (OR = 1.34) and biomass (OR = 1.35) for cooking were risk factors for AR. Burning mosquito coils and incense increased the risk of asthma and AR. Cat keeping (OR = 2.88), dog keeping (OR = 2.04), cockroaches (OR = 1.54) and rats or mice (OR = 1.46) were associated with asthma. Cockroaches increased the risk of AR (OR = 1.22). Air humidifier and air cleaner were linked to asthma and AR. Frequent cleaning and exposing bedding to sunshine were protective. In conclusion, urbanization, NO2 and traffic exhaust can increase the risk of adult asthma and AR. Higher ambient temperature was related to more asthma but less AR. Indoor animals such as cats, dogs, rats/mice and presence of cockroaches were associated with asthma or AR. Indoor chemical sources such as redecoration and new furniture were other risk factors. Cooking with natural gas or biomass and burning mosquito coils and incense were associated with asthma or AR. Frequent cleaning and exposing bedding to sunshine were protective.

We investigated associations between prenatal and postnatal environmental factors and onset and remission of preschool childhood eczema across China. The study population was preschoolers in randomized day care centers in seven cities (N = 39,782). Data on eczema and prenatal and postnatal indoor and outdoor environment were obtained from a cross-sectional questionnaire sent to parents or other guardians. Reports on eczema in the first 2 years and in the past year was used to retrospectively calculate onset and remission (changes of reported eczema). Prenatal and postnatal outdoor temperature, NO2 and PM10 were modelled from official air pollution data. Associations were estimated by two-level logistic regression. Calculated onset rate was 3.2%/y and remission rate 29.2%/y. Exposure to NO2 during pregnancy was associated with onset of eczema, similarly for all trimesters. Postnatal PM10 and NO2 were related to decreased remission. Postnatal outdoor temperature was associated with onset of eczema. Pre-natal and current redecoration or buying new furniture, and perinatal as well as current dampness and indoor mould, were associated with increased onset and decreased remission. Cockroaches in current home was another indoor risk factors. Prenatal exposure to farm environment and large family size were all negatively associated with eczema. In conclusion, a warmer climate and prenatal NO2 can be associated with increased onset of eczema in Chinese preschoolers. Postnatal PM10 and NO2 can be associated with reduced remission. Perinatal and current dampness, indoor mould and cockroaches may increase onset and decrease remission. Exposure to chemical emissions from indoor materials after first year of life may increase onset. Prenatal exposure to farm environment and large family size could be protective.

The long-term effects of ambient PM2.5 and chemical constituents on childhood pneumonia were still unknown. A cross-sectional study was conducted in 30,315 children in the China Children, Homes, Health (CCHH) project, involving 205 preschools in six cities in China, to investigate the long-term effects of PM2.5 constituents on lifetime-ever diagnosed pneumonia. Information on the lifetime-ever pneumonia and demographics were collected by validated questionnaires. The lifetime annual average ambient PM2.5, ozone and five main PM2.5 constituents, including SO42-, NO3-, NH4+, organic matter (OM) and black carbon (BC), were estimated according to preschool addresses by a combination of satellite remote sensing, chemical transport modeling and ground-based monitors. The prevalence of lifetime-ever diagnosed pneumonia was 34.5% across six cities and differed significantly among cities (p = 0.004). The two-level logistic regression models showed that the adjusted odds ratio for PM2.5 (per 10 µg/m3) and its constituents (per 1 µg/m3)-SO42-, NO3-, NH4+, and OM were 1.12 (95% CI:1.07-1.18), 1.02 (1.00-1.04), 1.06 (1.04-1.09), 1.05 (1.03-1.07) and 1.09 (1.06-1.12), respectively. Children in urban area, aged < 5 years and breastfeeding time < 6 months enhanced the risks of pneumonia. Our study provided robust results that long-term levels of ambient PM2.5 and its constituents increased the risk of childhood pneumonia, especially NH4+, NO3- and OM.

This paper studied associations between reported common cold and home dampness and mould, cleaning habits and ventilation, climate and outdoor air pollution in China among young adults without asthma or allergic rhinitis. Parents of children attending day care in eight Chinese cities answered a questionnaire on their health and home environment (75% response rate). We restricted the population to subject without asthma or allergic rhinitis (N = 37,275). Temperature and air pollution data was obtained from monitoring stations. Associations were estimated by multilevel logistic regression. Totally 12.5% reported common cold (≥3 colds) and 1.6% frequent common cold (≥5 colds) in the past 12 months. Female gender (OR = 1.53; 95% CI 1.37–1.71), residents in southern China (OR = 1.89; 95% CI 1.16–3.07) and living in homes with water leakage (OR = 1.32; 95% CI 1.16–1.50), mould odour (OR = 1.48; 95% CI 1.28–1.72), indoor mould (OR = 1.47; 95% CI 1.28–1.70), condensation on window panes (OR = 1.42; 95% CI 1.32–1.52) and damp bed clothing (OR = 1.19; 95% CI 1.11–1.28) were associated with common cold. Having many signs of dampness increased ORs. Daily cleaning (OR = 0.91; 95% CI 0.85–0.97) and mechanical ventilation in kitchen or bathroom (OR = 0.75; 95% CI 0.64–0.89) were protective. Higher mean ambient temperature (OR = 1.11 per °C; 95% CI 1.02–1.21), PM10 (OR = 1.17 per 10 μg/m3 ; 95% CI 1.14–1.21) and PM2.5 (OR = 1.28 per 10 μg/m3 ; 95% CI 1.20–1.37) were associated with common cold. The association with particulate air pollution was stronger in southern China. Similar associations were found for frequent common cold. In conclusion, indoor dampness and mould, a warmer climate and PM10 and PM2.5 can be associated with reported common cold. Further intervention and prospective studies are needed to verify causality of observed association in this cross-sectional study.

Background Few Chinese population studies exist on early life risk factors for furry pet allergy. Objectives We 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. Methods Children 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. Results Totally 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. Conclusions Prenatal 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 environmen

Respiratory droplets are bioaerosols that originate from the respiratory tract. Knowing their deposition characteristics during exhalation would facilitate the understanding of the source of large respiratory droplets and their importance in the spread of respiratory infectious diseases. In this study, computational fluid dynamics is used to simulate the motion and deposition of droplets released from either trachea or bronchi in a realistic reconstruction of the human respiratory tract. Influences of airflow structures and locations of droplet generation on droplet deposition are studied, and droplets with diameters between 1 and 50 mu m are examined. The deposition of droplets is found to be influenced mainly by the droplet diameter and the flow rate of exhalation. The number of droplets released from the trachea or bronchi that can escape into the environment decreases as the flow rate increases. When the flow rate is low (10 L/min), the critical diameter of droplets generated in the lower respiratory system that can escape into the air is approximately 12 mu m, but this diameter is approximately 5 mu m when the flow rate is medium (30 to 60 L/min) or large (90 L/min). The larynx is the dominant site of deposition for droplets smaller than the critical diameter, while trachea and bronchus are more important locations that account for the deposition of larger droplets. This study indicates that the lower respiratory tract is an important source of fine droplets (<5 mu m) in indoor environments, and larger droplets probably originate from the upper respiratory tract, which needs further investigation. Copyright, QC 20200728

This paper studied associations between reported common cold and home dampness and mould, cleaning habits and ventilation, climate and outdoor air pollution in China among young adults without asthma or allergic rhinitis. Parents of children attending day care in eight Chinese cities answered a questionnaire on their health and home environment (75% response rate). We restricted the population to subject without asthma or allergic rhinitis (N = 37,275). Temperature and air pollution data was obtained from monitoring stations. Associations were estimated by multilevel logistic regression. Totally 12.5% reported common cold (≥3 colds) and 1.6% frequent common cold (≥5 colds) in the past 12 months. Female gender (OR = 1.53; 95% CI 1.37–1.71), residents in southern China (OR = 1.89; 95% CI 1.16–3.07) and living in homes with water leakage (OR = 1.32; 95% CI 1.16–1.50), mould odour (OR = 1.48; 95% CI 1.28–1.72), indoor mould (OR = 1.47; 95% CI 1.28–1.70), condensation on window panes (OR = 1.42; 95% CI 1.32–1.52) and damp bed clothing (OR = 1.19; 95% CI 1.11–1.28) were associated with common cold. Having many signs of dampness increased ORs. Daily cleaning (OR = 0.91; 95% CI 0.85–0.97) and mechanical ventilation in kitchen or bathroom (OR = 0.75; 95% CI 0.64–0.89) were protective. Higher mean ambient temperature (OR = 1.11 per °C; 95% CI 1.02–1.21), PM10 (OR = 1.17 per 10 μg/m3 ; 95% CI 1.14–1.21) and PM2.5 (OR = 1.28 per 10 μg/m3 ; 95% CI 1.20–1.37) were associated with common cold. The association with particulate air pollution was stronger in southern China. Similar associations were found for frequent common cold. In conclusion, indoor dampness and mould, a warmer climate and PM10 and PM2.5 can be associated with reported common cold. Further intervention and prospective studies are needed to verify causality of observed association in this cross-sectional study.

Background Few Chinese population studies exist on early life risk factors for furry pet allergy. Objectives We 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. Methods Children 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. Results Totally 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. Conclusions Prenatal 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 environmen

This paper studied associations between reported common cold and home dampness and mould, cleaning habits and ventilation, climate and outdoor air pollution in China among young adults without asthma or allergic rhinitis. Parents of children attending day care in eight Chinese cities answered a questionnaire on their health and home environment (75% response rate). We restricted the population to subject without asthma or allergic rhinitis (N = 37,275). Temperature and air pollution data was obtained from monitoring stations. Associations were estimated by multilevel logistic regression. Totally 12.5% reported common cold (≥3 colds) and 1.6% frequent common cold (≥5 colds) in the past 12 months. Female gender (OR = 1.53; 95% CI 1.37–1.71), residents in southern China (OR = 1.89; 95% CI 1.16–3.07) and living in homes with water leakage (OR = 1.32; 95% CI 1.16–1.50), mould odour (OR = 1.48; 95% CI 1.28–1.72), indoor mould (OR = 1.47; 95% CI 1.28–1.70), condensation on window panes (OR = 1.42; 95% CI 1.32–1.52) and damp bed clothing (OR = 1.19; 95% CI 1.11–1.28) were associated with common cold. Having many signs of dampness increased ORs. Daily cleaning (OR = 0.91; 95% CI 0.85–0.97) and mechanical ventilation in kitchen or bathroom (OR = 0.75; 95% CI 0.64–0.89) were protective. Higher mean ambient temperature (OR = 1.11 per °C; 95% CI 1.02–1.21), PM10 (OR = 1.17 per 10 μg/m3 ; 95% CI 1.14–1.21) and PM2.5 (OR = 1.28 per 10 μg/m3 ; 95% CI 1.20–1.37) were associated with common cold. The association with particulate air pollution was stronger in southern China. Similar associations were found for frequent common cold. In conclusion, indoor dampness and mould, a warmer climate and PM10 and PM2.5 can be associated with reported common cold. Further intervention and prospective studies are needed to verify causality of observed association in this cross-sectional study.

Background Few Chinese population studies exist on early life risk factors for furry pet allergy. Objectives We 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. Methods Children 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. Results Totally 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. Conclusions Prenatal 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 environmen