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House dust mites produce well‐known allergens for asthma and allergy among children. To study house dust mite allergen exposure level in northeast China and characterize its association with indoor environmental factors and cleaning habits, we inspected 399 homes in Tianjin area and collected dust from mattresses. Dermatophagoides farinae (Der f) and Dermatophagoides pteronyssinus (Der p) were detected by the enzyme‐linked immunosorbent assay (ELISA) method. The medians of total allergen concentrations for spring, summer, autumn, and winter were 524 ng/g, 351 ng/g, 1022 ng/g, and 1010 ng/g. High indoor air relative humidity (RH), low air change rate, indoor dampness, and frequent changing of quilt cover/bedsheet/pillow case were significantly associated with high house dust mite allergen concentration (relative risk [RR]: RH, 1.18–1.34; air change rate, 0.97–1.00; dampness, 2.92–3.83; changing quilt cover/bedsheet/pillow case, 0.66–0.75). The decrease in the absolute humidity gradient between indoors and outdoors that occurs with increased air change rate may explain why a high ventilation reduces house dust mite allergen concentration. The findings of this study show the importance of ventilation and cleaning for controlling house dust mite allergens. We found that the decrease in additional absolute humidity (e.g., humidity indoor‐humidity outdoor) with increased air change rate may be the main reason that a high ventilation rate reduces house dust mite allergen concentration. Ventilation and cleaning should be both considered for creating a healthy home environment. [ABSTRACT FROM AUTHOR]

Building ventilation is important for occupants' health. There are few studies of associations between home ventilation and occupant's health in China. During 2013‐2016, we measured ventilation in 399 homes in Tianjin and Cangzhou, China, and surveyed the health history of children. Ventilation rates were measured using mass balance of occupant generated CO2. The associations of home ventilation with children's asthma and allergy were analyzed in different strata of time and space. A low bedroom ventilation at night was significantly associated with an increased proportion of rhinitis among children (rhinitis current, adjusted odds ratio (AOR): 1.59; 95% confidence interval (CI): 1.01‐2.49; diagnosed rhinitis, AOR: 3.02 (1.16‐7.89)). Our findings suggest a dose‐response relationship between ventilation rate at night in children's bedrooms and rhinitis current. The night‐time ventilation rate in bedrooms has a greater association with rhinitis than the whole home ventilation rate during daytime. [ABSTRACT FROM AUTHOR]

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]

In China, the prevalence rates of asthma and allergies have been increasing in past 50 years. Several epidemiological investigations have indicated that dampness is associated with health effects such as respiratory infections, asthma and allergy. This study aims to find the associations between home dampness and asthma, rhinitis and eczema among children. A cross-sectional study on dampness and asthma and allergy at Tianjin was launched in 2013. Questionnaires were used to survey indoor dampness and health outcomes of occupants. 3.5% parents reported that they have noticed visible mildew/mold in child's rooms. The association between water leakage and asthma among children was seemingly strong (AOR: 3.29, 95% CI: 1.75-6.19). The dampness in home may have influence on asthma, rhinitis and eczema among children. [ABSTRACT FROM AUTHOR]

Gas, coal and biomass fuels are the dominant energy fuels for cooking in China. Exposure to the smoke released from gas, coal and biomass fuels contributes to respiratory diseases in childhood. To identify the association between asthma and allergy and cooking fuels at homes in China, an epidemiological questionnaire study on the home environment and children's health was launched in Tianjin in 2013. Data for 7,865 children and homes are included in the study. The prevalence rate of diagnosed asthma, diagnosed pneumonia, diagnosed eczema, and diagnosed rhinitis among children was 4.5%, 27.9%, 38.6%and 19.6% respectively. Coal fuels used for daily cooking did have a significantly increased likelihood of asthma-related symptoms, doctor-diagnosed pneumonia and rhinitis ever. Children in families that used gas fuel for daily cooking had more pneumonia. Biomass/wood fuel was associated with a reduced risk for rhinitis. [ABSTRACT FROM AUTHOR]

Abstract: A study of “dorm environment and college students' health” was carried out in Tianjin, China, 2006–2007. It consisted of two phases. In Phase I, 3712 students in 1569 dorm rooms reported sick building syndrome (SBS) symptoms. One out of three students reported general SBS symptoms, and one out of four reported mucosal or skin problems. Males and females represented the same age group; had the same kind of dwellings in the same geographical area; and led similar student lifestyles. Nonetheless, female students reported slightly more SBS symptoms than males. A “moldy odor” or “dry air” was perceived by occupants in 31% and 76% dorm rooms respectively. The adjusted odds ratio (AOR) of perceived moldy odor for general SBS symptoms was 2.4, for mucosal symptoms 2.2, and for skin symptoms 2.0. A sensation of “dry air”, was a significant risk factor for general and skin symptoms. In Phase II, 238 dorm rooms were inspected and measured. Local moldy odor around room corners or under radiators was reported by inspectors in 26% dorm rooms. The median air change rate, indoor air temperature and relative humidity in winter were 0.7 h−1, 21 °C and 40%, respectively. Local moldy odor perceived by inspectors was a significant risk factor for nose irritation (AOR 2.8). In winter, higher air change rate was associated with a slight decrement of general and skin SBS symptoms, while higher indoor air temperature and relative humidity were slightly associated with reduced SBS symptoms. [Copyright &y& Elsevier]

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]

To study the association of indoor air quality and ventilation in Chinese homes with occupants' sick building syndrome (SBS) symptoms, we performed a study in 32 homes over four seasons in Tianjin, China. Measured indoor environmental parameters were ventilation rate, and concentrations of volatile organic compounds (VOCs), formaldehyde, PM 2.5 , ultrafine particle and ozone. Occupants reported any sick building syndrome symptoms for the previous three months. Ventilation rates at night in bedrooms were 0.35 h−1, 0.78 h−1, 0.37 h−1 and 0.41 h−1 in spring, summer, autumn and winter, respectively. A low ventilation rate at night (below the median value of 0.45 h−1) significantly increased the risk (adjusted odds ratio, aOR) of mucosal symptom to 2.65 (95% Confidence Interval (CI): 1.16–6.06). The aOR of ultrafine particle for mucosal symptom was 2.37 (95% CI: 1.02–5.49) and for dermal symptoms 3.96 (95% CI: 1.63–9.60). The aOR of ozone for dermal symptoms was 5.86 (95% CI: 1.19–28.99). Dry air perception that indicated a polluted indoor environment was a risk factor for SBS symptoms in Chinese homes. [ABSTRACT FROM AUTHOR]