Journal Staff

There are fewer longitudinal studies from China on symptoms as described for the sick building syndrome (SBS). Here, we performed a two-year prospective study and investigated associations between environmental parameters such as room temperature, relative air humidity (RH), carbon dioxide (CO2), nitrogen dioxide (NO2), sulphur dioxide (SO2), ozone (O-3), particulate matter (PM10), and health outcomes including prevalence, incidence and remission of SBS symptoms in junior high schools in Taiyuan, China. Totally 2134 pupils participated at baseline, and 1325 stayed in the same classrooms during the study period (2010-2012). The prevalence of mucosal symptoms, general symptoms and symptoms improved when away from school (school-related symptoms) was 22.7%, 20.4% and 39.2%, respectively, at baseline, and the prevalence increased during follow-up (P<0.001). At baseline, both indoor and outdoor SO2 were found positively associated with prevalence of school-related symptoms. Indoor O-3 was shown to be positively associated with prevalence of skin symptoms. At follow-up, indoor PM10 was found to be positively associated with new onset of skin, mucosal and general symptoms. CO2 and RH were positively associated with new onset of mucosal, general and school-related symptoms. Outdoor SO2 was positively associated with new onset of skin symptoms, while outdoor NO2 was positively associated with new onset of skin, general and mucosal symptoms. Outdoor PM10 was found to be positively associated with new onset of skin, general and mucosal symptoms as well as school-related symptoms. In conclusion, symptoms as described for SBS were commonly found in school children in Taiyuan City, China, and increased during the two-year follow-up period. Environmental pollution, including PM10, SO2 and NO2, could increase the prevalence and incidence of SBS and decrease the remission rate. Moreover, parental asthma and allergy (heredity) and pollen or pet allergy (atopy) can be risk factors for SBS

Optimizing outdoor smoking points outside large exhibition halls based on real-time on-site PM2.5 and CO2 monitoring

BackgroundImproper settings of outdoor smoking points in public places may increase the risk of secondhand smoke exposure among the population. Conducting research on air pollution in and around smoking spots and related influencing factors can provide valuable insights for optimizing the setting of outdoor smoking points. ObjectiveTo investigate the influence of the number of smokers at outdoor smoking points and the distance on the diffusion characteristics of surrounding air pollutants, in order to optimize the setting of outdoor smoking points. MethodsSurrounding the exhibition halls in the China International Import Expo (CIIE), two outdoor smoking points were randomly selected, one on the first floor (ground level) and the other on the second floor (16 m above ground), respectively. At 0, 3, 6, and 9 m from the smoking points in the same direction, validated portable air pollutant monitors were used to measure the real-time fine particulate matter (PM2.5) and carbon dioxide (CO2) concentrations for consecutive 5 d during the exhibition, as well as the environmental meteorological factors at 0 m with weather meters including wind speed, wind direction, and air pressure. An open outdoor atmospheric background sampling point was selected on each of the two floors to carry out parallel sampling. Simultaneously, the number of smokers at each smoking point were double recorded per minute. The relationships between the number of smokers, distance from the smoking points, and ambient PM2.5 and CO2 concentrations were evaluated by generalized additive regression models for time-series data after adjustment of confounders such as temperature, relative humidity, and wind speed. ResultsThe median numbers of smokers at smoking points on the first and second floors were 6 [interquartile range (IQR): 3, 9] and 9 (IQR: 6, 13), respectively. Windless (wind speed <0.6 m·s−1) occupied most of the time (85.9%) at both locations. The average concentration of ambient PM2.5 at the smoking points (0 m) [mean ± standard deviation, (106±114) μg·m−3] was 4.2 times higher than that of the atmospheric background [(25±7) μg·m−3], the PM2.5 concentration showed a gradient decline with the increase of distance from the smoking points, and the average PM2.5 concentration at 9 m points [(35±22) μg·m−3] was close to the background level (1.4 times higher). The maximum concentration of CO2 [(628±23) μmol·mol−1] was observed at 0 m, and its average value was 1.3 times higher than that of the atmospheric background [(481±40) μmol·mol−1], and there was no gradient decrease in CO2 concentration with increasing distance at 0, 3, 6, and 9 m points. The regression analyses showed that, taking smoking point as the reference, every 3 m increase in distance was associated with a decrease of ambient PM2.5 by 24.6 [95% confidence interval (95%CI): 23.5, 25.8] μg·m−3 (23.2%) and CO2 by 54.1 (95%CI: 53.1, 55.1) μmol·mol−1 (8.6%). Every one extra smoker at the smoking point was associated with an average increase of PM2.5 and CO2 by 2.0 (95%CI: 1.7, 2.8) μg·m−3 and 1.0 (95%CI: 0.7，1.2) μmol·mol−1, respectively. The sensitivity analysis indicated that, under windless conditions, the concentrations of PM2.5 and CO2 at the smoking points were even higher but the decreasing and dispersion characteristics remained consistent. ConclusionOutdoor smoking points could significantly increase the PM2.5 concentrations in the surrounding air and the risks of secondhand smoke exposure, despite of the noticeable decreasing trend with increasing distance. Considering the inevitable poor dispersion conditions such as windless and light wind, outdoor smoking points are recommended to be set at least 9 m or farther away from non-smoking areas

Prevalence of Childhood Atopic Dermatitis: An Urban and Rural Community-Based Study in Shanghai, China

Background: Atopic dermatitis (AD) is a common inflammatory and chronically relapsing disorder with increasing prevalence. However, little is known about its prevalence in Shanghai, the top metropolitan of China. This study will estimate and compare the prevalence of AD in urban and rural areas in representative samples of 3 to 6-year-old children in Shanghai. Methodology/Principal Findings: A descriptive cross-sectional study was performed. Pre-school children were obtained by cluster sampling from 8 communities in different districts in Shanghai. The main instrument was the core questionnaire module for AD used in the U.K. Working Party’s study. All the data were statistically analyzed by EpiData 3.1 and SPSS16.0. A total of 10436 children completed the study satisfactorily, with a response rate of 95.8%. The prevalence of AD in 3 to 6-year-old children was 8.3 % (Male: 8.5%, Female: 8.2%). The prevalence in urban areas of Shanghai was gradiently and significantly higher than that in rural areas. The highest prevalence was in the core urban area (10.2 % in Xuhui Tianping) vs. the lowest far from the urban areas (4.6 % in Chongming Baozhen). Conclusions/Significance: The prevalence of AD was 8.3 % (95%CI: 7.6%–9.1%) in children aged 3 to 6 in Shanghai. Th

Ten cities cross-sectional questionnaire survey of children asthma and other allergies in China

Asthma, rhinitis and eczema (allergic or non-allergic) have increased throughout the world during the last decades, especially among children. Changes in the indoor environment are suspected to be important causes. China has experienced a dramatic change in indoor environmental exposures during the past two decades. However, such changes and their associations with children's asthma and other health aspects have not been thoroughly studied. China, Children, Homes, Health (CCHH), Phase I, was a cross-sectional questionnaire survey of 48219 children 1-8 years old in 10 Chinese cities during 2010-2012. The questionnaire includes the International Study of Asthma and Allergies in Childhood (ISAAC) core health questions and additional questions regarding housing, life habits and outdoor environment. In health analyses, children aged 3-6 years old were included. The prevalences of doctor diagnosed asthma varied from 1.7% to 9.8% (mean 6.8%), a large increase from 0.91% in 1999 and 1.50% in 2000. The prevalence of wheeze, rhinitis and atopic eczema (last 12 months) varied from 13.9% to 23.7%, 24.0% to 50.8% and 4.8% to 15.8%, respectively. Taiyuan had the lowest prevalences of all illnesses and Shanghai the highest, except for wheezewhere the highest value was for Urumqi. We found (1) no obvious association between disease prevalences and ambient PM10 concentrations and (2) higher prevalences of disease in humid climates with hot summers and cold winters, but with no centrally heated buildings. Associations between the diseases and economic status as indexed by Gross Domestic Product (GDP) requires further study.</p

Indoor and Outdoor Air Pollution in Relation to Allergy and Asthma in Taiyuan, China

The aim was to study the prevalence of asthma, eczema, allergy and respiratory symptoms among pupils in Shanxi province, China, in relation to home and school environment and outdoor air pollution. In one study there was a low prevalence of self-reported asthma, eczema and pollen or pet allergy among pupils (9-20y). Rural childhood and consumption of fruit and fish were negatively associated with asthma or allergy, while current urban residency and consumption of hamburgers tended to be risk factors. In another study in junior high school pupils, similar low prevalence of asthma and allergy was found. Compared with pupils at the same age in Uppsala, Sweden, asthma and allergy were less common while daytime attacks of breathlessness were more common in Chinese pupils. Parental asthma or allergy was a predictor of asthma symptoms. Factors in the home environment such as new floor, new furniture and ETS exposure were risk factors for asthma symptoms. Crowdedness, dust amount, CO2, temperature and air humidity were negatively associated with respiratory symptoms. Microbial chemical components like muramic acid and ergosterol, markers for bacteria and fungi, were negatively associated with wheeze or daytime attacks of breathlessness. The associations with endotoxin varied depending on the length of 3-hydroxy fatty acids of the lippopolysaccharides (LPS). Among outdoor air pollutants, SO2 and formaldehyde were positively associated with asthma symptoms or respiratory infections. In addition, indoor SO2, NO2 and formaldehyde were positively associated with asthma symptoms and respiratory infections. In conclusion, rural childhood and dietary factors can be protective for asthma and allergy. ETS and chemical emissions from new material at home can be risk factors for asthmatic symptoms. In the school environment, factors of indoor origin seemed to be generally protective for respirator symptoms while factors of outdoor origin seemed to be risk factors

Carbon dioxide (CO2) demand-controlled ventilation in university computer classrooms and possible effects on headache, fatigue and perceived indoor environment: an intervention study

PurposeTo study the effects of a CO2 demand-controlled ventilation system (variable flow) in computer classrooms on perceived air quality and sick building syndrome.MethodsUniversity students (27 % women) participated in a blinded study. Two classrooms had variable flow (mean 5.56 ac/h); two others had constant ventilation flow (mean 5.07 ac/h). After one week, ventilation conditions were shifted. The students reported symptoms/perceptions during the last hour on rating scales. Temperature, air humidity, CO2, PM10 and number concentration of particles were measured simultaneously. Cat (Fel d 1), dog (Can f 1), horse (Equ cx) and house dust mites (Der f 1 and Der p 1) allergens were measured in dust. Those participating twice in the same classroom (N = 61) were analysed longitudinally.ResultsMean CO2 was 784 ppm (9 % of time &gt;1,000 ppm) with variable flow and 809 ppm with constant flow conditions (25 % of time &gt;1,000 ppm). Mean temperature (22.6 °C), PM10 (18 μg/m3) and number concentration (1,860 pt/cm3) were unchanged. The median levels of cat, dog, horse and Der f 1 allergens were 10,400 ng/g, 4,900 ng/g, 13,700 U/ng and 260 ng/g dust, respectively. There were slightly less headache (p = 0.003), tiredness (p = 0.007) and improved perceived air quality (p = 0.02) with variable flow.ConclusionsUse of a CO2-controlled ventilation system, reducing elevated levels of CO2, may slightly reduce headache and tiredness and improve perceived air quality. The high levels of pet allergens, due to track in of allergens from the home and possible accumulation due to electrostatic forces, illustrate a need for improved cleaning.</p

Indoor and Outdoor Air Pollution in Relation to Allergy and Asthma in Taiyuan, China [Elektronisk resurs]

The aim was to study the prevalence of asthma, eczema, allergy and respiratory symptoms among pupils in Shanxi province, China, in relation to home and school environment and outdoor air pollution. In one study there was a low prevalence of self-reported asthma, eczema and pollen or pet allergy among pupils (9-20y). Rural childhood and consumption of fruit and fish were negatively associated with asthma or allergy, while current urban residency and consumption of hamburgers tended to be risk factors. In another study in junior high school pupils, similar low prevalence of asthma and allergy was found. Compared with pupils at the same age in Uppsala, Sweden, asthma and allergy were less common while daytime attacks of breathlessness were more common in Chinese pupils. Parental asthma or allergy was a predictor of asthma symptoms. Factors in the home environment such as new floor, new furniture and ETS exposure were risk factors for asthma symptoms. Crowdedness, dust amount, CO2, temperature and air humidity were negatively associated with respiratory symptoms. Microbial chemical components like muramic acid and ergosterol, markers for bacteria and fungi, were negatively associated with wheeze or daytime attacks of breathlessness. The associations with endotoxin varied depending on the length of 3-hydroxy fatty acids of the lippopolysaccharides (LPS). Among outdoor air pollutants, SO2 and formaldehyde were positively associated with asthma symptoms or respiratory infections. In addition, indoor SO2, NO2 and formaldehyde were positively associated with asthma symptoms and respiratory infections. In conclusion, rural childhood and dietary factors can be protective for asthma and allergy. ETS and chemical emissions from new material at home can be risk factors for asthmatic symptoms. In the school environment, factors of indoor origin seemed to be generally protective for respirator symptoms while factors of outdoor origin seemed to be risk factors.</p