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

From October 2010 to April 2012, we conducted a cross‐sectional study of associations between household environments and childhood health among preschool children in eight Chinese cities. Here, we analyze associations of early household renovation with preterm birth (PTB), low birthweight (LBW), term low birthweight (Term‐LBW), and small for gestational age (SGA). Parents responded to questions about household renovation and their children's gestational age and birthweight. In the multivariate logistic regression analyses, household renovation in the year before pregnancy was significantly associated with LBW (sample size: N = 25 813; adjusted odds ratio (OR) with 95% confidence intervals (CIs): 1.23, 1.01‐1.50) and Term‐LBW (N = 24 823; 1.29, 1.01‐1.67). Household renovation during pregnancy was significantly associated with PTB (N = 25 202; 1.28, 1.01‐1.69). These significant associations were also found in the two‐level (city‐child) logistic regression analyses and in the sensitivity analyses among 21 009 children with complete data in all studied variates. Stronger associations were found in certain subgroups. Our findings indicate that household renovation within one year before pregnancy might be a risk factor for LBW and Term‐LBW, while household renovation during pregnancy could be a risk factor for PTB. [ABSTRACT FROM AUTHOR]

This study investigated the association of building characteristics and occupant behaviours with building dampness indicators. Data were from a cross-sectional study in urban Tianjin and rural Cangzhou, China, from 2013 to 2014. We studied two fundamental types of Chinese dwellings: bungalows typical of rural locales and apartments in low- and high-rise buildings typical of urban settings. Occupants of bungalows reported more dampness indicators than apartment dwellers. Risk factors for one or more dampness indicators included natural ventilation without fans, older dwellings and coal stove or Kang heating system (a brick bed installed in the bedroom for heating and sleeping). All these factors were typical of bungalows, which generally used older building technologies including non-insulated external walls, wooden frame windows, electric fans for cooling and no exhaust fan ventilation. Occupant behaviours that decreased the risk for dampness indicators included frequent window opening and daily cleaning, regardless of the type of dwelling. Indoor dampness was highly correlated with mouldy and humid odour, and paradoxically (although not a new finding) with the perception of air dryness. [ABSTRACT FROM AUTHOR]

It is very important to know the current level of indoor pollution and occupants' ventilation habits. With this aim, this study presents an investigative project that covered five climate zones in China. The project consisted of two parts: long-term monitoring and seasonal measurements. For the long-term monitoring, we installed indoor air quality (IAQ) sensors, window state sensors, and mechanical ventilation sensors inside homes. In regard to IAQ, The median indoor 24-h averaged PM2.5 concentration ranged from 18 to 49 μ g / m 3 . The indoor and outdoor 24-h averaged PM2.5 concentrations were similar for most of the regions. The 24-h averaged indoor CO 2 concentrations were lower than 1000 ppm for all regions in all four seasons. Northern China usually had higher indoor CO 2 concentrations than did southern China. In regard to occupants' behavior, in naturally ventilated homes, both the window-opening probability and open-window duration per day increased from the north to the south of China in winter. According to the example of mechanically ventilated Apartments, where pressure sensors were used to monitor the relative pressure at the air outlet of a mechanical ventilation system, the occupants used the ventilation system mainly in winter and spring. For the seasonal investigation, indoor formaldehyde concentrations in 224 homes were measured in four seasons (sampling time: 20 min). In summer, the indoor formaldehyde concentration reached its peak for the year, with about 35% of homes having concentrations larger than 100 μ g / m 3 under closed conditions (doors and windows have been closed for more than 12 h). [ABSTRACT FROM AUTHOR]

The aim of this study was to understand occupant thermal comfort and air-conditioning (AC) usage behavior in mixed-mode dwellings in China. Longitudinal field measurements were conducted in 43 homes in Tianjin during the warm half of the year, May through November 2016. Room air temperatures and AC on/off events were recorded continuously using autonomous data-logging devices (iButtons). Occupants’ “ right-here-right-now ” thermal responses were collected through an online questionnaire delivered intermittently to their smartphones throughout the survey period. A total of 4157 AC events and 1697 online questionnaires were collected and then matched against concurrent indoor and outdoor temperatures. Results indicate that thermal sensations of the Tianjin residents were less sensitive to variations of the room temperature, compared to findings from previous studies conducted in offices. The indoor temperature limits corresponding to 80% thermal acceptability for our Tianjin residential sample were estimated to be 21.0   °C (the lower limit) and 27.3 °C (the upper limit). Average “trigger temperature” for AC cooling in summer was 27.6   °C resulting in a cooling of the room by 4.1   °C on average, and the average trigger temperature for AC heating in winter was 18.6   °C heating the room by 6.6   °C. Our analysis also indicated that the householder's education level and household income were associated with their AC usage decisions. [ABSTRACT FROM AUTHOR]

This study investigates associations of building dampness indicators, and perceptions of moldy odor, humidity and dryness (Dampness and Dryness, D&D) with children's asthma and allergies. Data were obtained from a cross-sectional study in Tianjin and Cangzhou, China from 2013 to 2014. Completed surveys were returned by 7366 families with children 0–8 years old. We studied D&D factors both in the current residence and the residence where the children lived immediately after birth. A total of 4.4% of the children had doctor-diagnosed asthma; 9.5% had doctor-diagnosed rhinitis; and 39.1% had doctor-diagnosed eczema. Most of the dampness indicators, perceptions of odors, and perceived dryness, were significantly associated with children's asthma and allergies. A reporting bias in parents (or guardians) who themselves had allergies was not found to be the reason for the associations between D&D and health effects. Compared with either previous or current exposure to D&D, continuous exposure to D&D was a greater risk for children's asthma and allergies. Perceived dryness was the most important studied risk factor for children's allergies in either current or previous homes. [ABSTRACT FROM AUTHOR]

Air change rate data for dwellings in China are scarce. We carried out a study of ventilation rates in 399 homes in Tianjin and Cangzhou, China. Carbon dioxide concentration was continuously measured for 24 h in bedrooms and living rooms. The air change rate at night was calculated using a single zone mass balance model. In the whole home, the median air change rates during sleeping time for spring, summer, autumn and winter were 0.27 h −1 , 1.11 h −1 , 0.29 h −1 , 0.30 h −1 . In the child's bedroom with closed window and door, the median air change rates during sleeping time for spring, summer, autumn and winter were 0.25 h −1 , 0.25 h −1 , 0.30 h −1 , 0.37 h −1 . Air change rates in homes with open windows were significantly higher than those in homes with closed windows ( p  = 0.000). [ABSTRACT FROM AUTHOR]

The escalation of energy consumption in buildings and heightened concerns about acceptable indoor air quality stimulate interest in the usage of air cleaner as an adjunct for indoor environmental conditioning. A regenerative desiccant wheel integrated into a ventilation system termed Clean-Air Heat Pump (CAHP) can improve the air quality during the process of dehumidification without using additional energy. An experimental study in a field lab was performed to investigate the air cleaning performance of CAHP. Photoacoustic gas analyzer-INNOVA was used to characterize chemical removal of indoor air pollutants by the CAHP. The results revealed that all the detected VOCs were removed effectively by the CAHP with an average single pass efficiency of 82.7% when the regeneration temperature for desiccant wheel was 60 °C. The mass balance between adsorption and desorption of the desiccant wheel was 96.8%, which indicated that the most of gaseous pollutants were not accumulated in the CAHP. The regeneration temperature for the wheel could affect the air purification performance of CAHP. At 70 °C of regeneration temperature, the air-cleaning efficiency reached 96.7%. Up to 70% of the outdoor air ventilation can be saved with the operation of CAHP. The clean air deliver rate (CADR) was over threefold of the outdoor air supply rate when CAHP was in operation. [ABSTRACT FROM AUTHOR]

[Display omitted] • A thermal comfort picture in Chinese residential buildings was illustrated. • Indoor thermal environment in rural dwellings were worse than those in urban area. • Residents in HSCW zones were the most tolerant to thermal environment. • Adaptive models were summarized, occupants in rural area have stronger adaptability. Amid the backdrop of the energy crisis, thermal comfort is crucial to achieve energy savings. Residential buildings are characterized by a wide range of adaptive comfort opportunities. However, there has been a lack of systematic refinement and review of residential thermal comfort field studies in China to provide valuable recommendations for energy conservation. We systematically reviewed studies on thermal environment and thermal comfort in Chinese residential buildings published in peer-reviewed journals up to 2020. A total of 34 studies were deemed to have provided sufficient information on both the thermal environment and thermal comfort. We found that in winter, there were obvious differences between urban and rural dwellings in Severe Cold (SC) and Cold (C) zones, with regard to their indoor air temperature (urban: 19.8 ∼ 25.0 °C v.s. rural: 11.3 ∼ 17.8 °C) and neutral temperature (urban: 17.6 ∼ 25.1 °C v.s. rural: 11.9 ∼ 23.45 °C). While in summer, the indoor air temperature in urban dwellings were slightly lower than those in rural areas due to their prevalent use of air conditioner (urban: 26.1 ∼ 28.9 °C v.s. rural: 29.5 ∼ 34.9 °C). Indoor air temperature and neutral temperature varied considerably in different climate zones in winter. In SC zones, the indoor environment was overheated, which could lead to energy wastage and overheating discomfort for residents. Residents in Hot-Summer and Cold-Winter (HSCW) zone were the most tolerant to the variation of thermal environment (the median coefficient of MTS or TSV equation: SC: 0.18; C: 0.20; HSCW: 0.13; HSWW: 0.23). [ABSTRACT FROM AUTHOR]

Exposure to indoor formaldehyde has been reported to be relevant to several adverse health effects, especially in occupational exposure scenarios. In this study, a systematic review and meta-analysis has been conducted for epidemiological studies published between January 1980 and December 2017 in order to summarize available evidence and to obtain concentration-response (C-R) relationships between different health outcomes and formaldehyde exposure in residences, offices or schools. We searched four databases to identify the related studies. Finally, we selected 31 studies through the systematic review, and included 23 studies in the meta-analysis. The results show that the pooled odds ratios (ORs) for asthma in children were 1.27 (95% CI: 1.20–1.35) in eastern countries and 1.03 (95% CI: 1.02–1.04) in western countries per 10 μg/m3 increase in formaldehyde concentration. For asthma in adults, the pooled OR was 1.09 (95% CI: 1.03–1.15) per 10 μg/m3 increase of formaldehyde concentration. We did not obtain significant associations of formaldehyde exposure with dermatitis or rhinitis. Our findings provide robust evidences for C-R relationships of formaldehyde exposure in civil buildings for different adverse health outcomes. The obtained C-R relationships can be helpful to estimate the attributable disease burden of indoor formaldehyde exposure. [Display omitted] [ABSTRACT FROM AUTHOR]

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. • Mold and dampness were associated with allergic rhinitis and asthma. • Mold and dampness were related to odor perceptions. • Different types of odors were associated with allergic rhinitis and asthma. • Odors were partly mediators of the effects of indoor dampness on rhinitis and asthma. [ABSTRACT FROM AUTHOR]

Low birth weight (LBW), as a major concern in public health, is now increasing worldwide, but its main indoor environmental factors remain unclear. 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. 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 traffic-related air pollutant (NO 2), industrial pollutant (SO 2), and inhalable particulate matter (PM 10), 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). 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 PM 2.5 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. Our findings indicate that long-term exposure to indoor mould/damp stains and mouldy odour in utero plays a key role in LBW, and this association can be significantly modified by some specific personal, indoor, and outdoor factors. [Display omitted] • Mould/damp stains exposure was significantly associated with term-low birth weight (LBW). • Maternal exposure to residential mouldy odour significantly increased the risk of preterm-LBW. • High temperature and PM 2.5 enhanced LBW risk of mould/damp stains and mouldy odour. • Families with pets were more susceptible to LBW risk of mould/damp stains and mouldy odour. • Our study has a new implication for the effective reduction and early prevention of LBW. [ABSTRACT FROM AUTHOR]

More than 8 million people fly on commercial aircraft each day with approximately 5% having a pre-existing respiratory disease. Thus it is necessary to provide high air quality in aircraft to protect public health. Volatile organic compounds (VOCs) present in aircraft cabins are suspected to contribute to the reported complaints. We investigated concentrations of VOCs, air temperature, relative humidity, and CO 2 concentrations in a total of 46 flights, including 26 Chinese domestic flights and 20 international flights. We focused on the data from the cruising phase without meal serving in which the air supply and air recirculation were steady. A total of 284 passengers (i.e., 101 on international flights and 183 on Chinese domestic flights) were invited to participate in questionnaire surveys in this phase. We performed a linear mixed model analysis by controlling for potential confounders (age, gender, smoke habits, and history of allergy) to study associations between VOCs exposures and passengers' complaints. Xylene was significantly associated with irritations of the eyes, nose, and throat on both international and domestic flights, with antilog beta values from 1.12 to 1.28 (p < 0.05). The association of some aldehydes (i.e., nonanal, decanal, and heptanal), which are potential oxidation products with ozone, with passengers' sensory irritations was also significant, especially during international flights (antilog beta values: 1.19–1.22). It indicates that VOCs, especially xylene and aldehydes, in aircraft cabins may influence the perceived indoor air quality and complaints among passengers. • We focused on the association of targeted VOCs with subjective perceptions in cabin environment. • Higher exposure to toluene was a risk factor for sensory irritation, headache and fatigue. • Xylene and ozone-initiated by products were related to sensory irritations among passengers. [ABSTRACT FROM AUTHOR]

Fine particulate matter (PM 2.5) pollution is of national concern in China. Indoor PM 2.5 concentrations may contribute significantly to human exposure because people spend most of their time indoors. In this study, we systematically reviewed the level of indoor PM 2.5 concentrations in residences, offices, and schools in China. We looked for corresponding literature published between 1980 and 2019 in six major literature databases and finally obtained 118 articles. We then summarized the spatial distribution of indoor PM 2.5 concentrations in urban and rural areas, analyzed the indoor PM 2.5 concentrations in residences, offices, and schools in urban areas across three time periods, and compared the indoor PM 2.5 concentration levels in the urban and rural areas. It was found that the urban areas considered are mainly distributed in the middle and eastern part of China, while the rural areas are mainly distributed in northeast, north, and southwest China. Indoor PM 2.5 concentrations have decreased significantly in the past decades. The mean ± SD value of indoor PM 2.5 concentration decreased from 127.5 ± 111.4 μg/m³ prior to 2010 to 70.1 ± 35.2 μg/m³ following 2015. The indoor PM 2.5 concentration in rural areas was much higher than that in urban areas. The mean ± SD value of indoor PM 2.5 concentrations in rural residences was up to 275.7 ± 326.4 μg/m³, while that in urban residences was 95.4 ± 71.0 μg/m³. A long-term national indoor PM 2.5 concentration measurement is suggested to obtain a more comprehensive and accurate indoor PM 2.5 concentration level. • 118 articles with measured indoor PM 2.5 concentrations in China were reviewed. • The indoor PM 2.5 concentrations in rural areas exceeded those in urban areas. • Harbin and Lhasa showed the highest and lowest urban concentrations in 2010–2015. • The highest and lowest urban concentrations were in Taian and Changchun after 2015. • Lhasa and Wuwei had the highest and lowest rural concentrations. [ABSTRACT FROM AUTHOR]

We performed a cross‐sectional survey of 2143 female students in a university in Tianjin, China regarding perceived air quality (PAQ) and sick building syndrome (SBS) symptoms in the student dormitory. The prevalence of general, mucosal, and skin symptoms was 22.1%, 21.9%, and 26.3%, respectively. The three most prevalent PAQ complaints were "dry air" (48.9% often), "stuffy odor" (18.2%), and "other unpleasant odors" (5.1%), and they were significant risk factors for 11–12 out of 12 SBS symptoms (adjusted odds ratios [AOR]: 1.6–5.8). Survey data of 1471 undergraduates, whose dorms were of uniform layout and furnishing, were used to further investigate the influences of occupancy level and occupant behaviors on PAQ and SBS symptoms. Frequent use of air freshener/perfume was a significant risk factor for "dry air," less frequent room cleaning and higher occupancy density were significant risk factors for "stuffy odor," and less natural ventilation was a significant risk factor for both "stuffy odor" and "pungent odor." These factors were also significantly associated with some SBS symptoms. In particular, the use of air freshener/perfume exhibited a significant dose–response pattern with "fatigue" (sometimes: AOR 1.3; often: AOR 2.0) and with "irritated, stuffy, or runny nose" (sometimes: AOR 1.6; often: AOR 2.2). [ABSTRACT FROM AUTHOR]

• A new survival model was proposed to predict window opening behavior. • Window opening duration was introduced as an independent variable into the model. • Survival model outperforms Logistic model on dynamic description of window switching. • Model prediction accuracy can be improved by considering occupant living habits. Natural ventilation can reduce a building's energy consumption while improving indoor thermal comfort and air quality. However, window opening behavior is prominently random and highly dependent on meteorological conditions. It is of considerable significance to explore indicators influencing window opening behavior and establish a model to predict the window opening probability. In this study, four environmental indicators significantly influencing window opening behavior (indoor air temperature, the concentration of CO 2 , outdoor air temperature, and the concentration of PM 2.5) were screened out from the measurement. With the selected indicators as input variables, the Cox model for survival analysis was established. For comparison, the logistic model was also established, coupled with the Cox model, to simulate the window opening probability under the interaction of environmental indicators. According to the comparison results, although slightly less accurate than the existing logistic model in predicting the window opening probability throughout whole survival lifetime, the accuracy of the Cox model was 1.3% more than that of the logistic model, which will provide a foundation for further revision of the human behavior model. [ABSTRACT FROM AUTHOR]

SBS (Sick Building Syndrome) has been studied since the 1970s, mostly in workplaces. To comprehensively characterize associations between the home environment and SBS, we performed a study in the Tianjin area, China. Seven thousand eight hundred and sixty-five (7865) families with infants participated in a questionnaire survey. Information on their lifestyles, home environment and health outcomes was obtained. Fourteen percent (14%) of parents reported general symptoms, followed by 11% for mucosal symptoms and 9% for skin symptoms. There was no gender difference in reports of SBS symptoms. People living in apartments, compared to Pingfang, reported more SBS symptoms. Indoor risk factors for SBS symptoms were perceived dry air (AOR:2.71–3.85), condensation on windows (AOR:1.44–2.11), less frequent window opening (AOR:1.71–1.73) and dampness (AOR:1.44–1.93). Our findings suggest that the home environment impacts occupants' health. • A comprehensive analysis of sick building syndrome (SBS) symptoms in homes. • There was no gender difference for SBS symptoms. • Dry air perception, not due to physical dryness, was a strong and consistent risk factor for SBS symptoms. • Low ventilation and dampness were also risks for SBS symptoms. [ABSTRACT FROM AUTHOR]

The available information on endotoxin in Chinese households is limited and there is inconsistency regarding its impact on asthma and allergies in children. A case-control study was performed in 324 homes in Tianjin, China. Linear regression analysis was performed to identify the determinants of endotoxin concentrations in household dust. Logistic regression models were employed to investigate the associations of endotoxin concentrations with asthma and allergies in children. Endotoxin concentrations were determined from 284 valid dust samples, ranging from 94 to 11,625 EU/g, with a mean concentration of 3638 EU/g. We found a significant positive association between endotoxin concentrations and children's current asthma. Old houses, ventilation systems without exhaust fans and windows opened infrequently were related to higher concentrations of endotoxins. In conclusion, endotoxin exposure in the home might be a risk factor for current asthma in children. Strategies for controlling endotoxin concentrations such as building maintenance and ventilation improvements are recommended. [ABSTRACT FROM AUTHOR]

The burden of disease attributed to the indoor exposure to sulfur dioxide (SO2), nitrogen dioxide (NO2), ozone (O3), and carbon monoxide (CO) is not clear, and the quantitative concentration–response relationship is a prerequisite. This is a systematic review to summarize the quantitative concentration–response relationships by screening and analyzing the polled effects of population‐based epidemiological studies. After collecting literature published between 1980 and 2019, a total of 19 health outcomes in 101 studies with 182 health risk estimates were recruited. By meta‐analysis, the leave‐one‐out sensitivity analysis and Egger's test for publication bias, the robust and reliable effects were found for SO2 (per 10 μg/m3) with chronic obstructive pulmonary diseases (COPD) (pooled relative risks [RRs] 1.016, 95% CI: 1.012–1.021) and cardiovascular diseases (CVD) (RR 1.012, 95%CI: 007–1.018), respectively. NO2 (per 10 μg/m3) had the pooled RRs for childhood asthma, preterm birth, lung cancer, diabetes, and COPD by 1.134 (1.084–1.186), 1.079 (1.007–1.157), 1.055 (1.010–1.101), 1.019 (1.009–1.029), and 1.016 (1.012–1.120), respectively. CO (per 1 mg/m3) was significantly associated with Parkinson's disease (RR 1.574, 95% CI: 1.069–2.317) and CVD (RR 1.024, 95% CI: 1.011–1.038). No robust effects were observed for O3. This study provided evidence and basis for further estimation of the health burden attributable to the four gaseous pollutants. [ABSTRACT FROM AUTHOR]