Chanjuan Sun

Associations of gestational and early life exposures to ambient air pollution with childhood respiratory diseases in Shanghai, China: A retrospective cohort study

BACKGROUND Associations of ambient air pollutants with respiratory health are inconsistent. OBJECTIVES We analyzed the associations of gestational and early life exposures to air pollutants with doctor-diagnosed asthma, allergic rhinitis, and pneumonia in children. METHODS We selected 3358 preschool children who did not alter residences after birth from a cross-sectional study in 2011-2012 in Shanghai, China. Parents reported childrens respiratory health history, home environment, and family lifestyle behaviors. We collected daily concentrations of sulphur dioxide (SO2), nitrogen dioxide (NO2), and particulate matter with an aerodynamic diameter ≤10μm (PM10) during the childs total lifetime (2006-2012) for each district where the children lived. We analyzed the associations using logistic regression models. RESULTS After adjusting for covariates and the other studied pollutants, we found that exposure to NO2 (increment of 20μg/m(3)) during the first year of life was significantly associated with asthma [odds ratio (OR)=1.77; 95% confidence interval (CI): 1.29-2.43] and allergic rhinitis (OR=1.67; 95% CI: 1.07-2.61). Exposure to NO2 during gestation, the first two and three years, and over total lifetimewas all consistently associated with increased odds of allergic rhinitis. Quartiles of NO2 concentration during different exposure periods showed a slight dose-response relationship with the studied diseases. These diseases had significant associations with pollutant mixtures that included NO2, but had no significant association with exposures to SO2 and PM10 individually or in mixtures. CONCLUSIONS Gestational and early life exposures to ambient NO2 are risk factors for childhood respiratory diseases.

Associations of gestational and early life exposures to ambient air pollution with childhood atopic eczema in Shanghai, China

Whether ambient air pollution is associated with childhood atopic eczema is controversial. In this paper, we selected 3358 preschool children who had not altered residences since pregnancy from a cross-sectional study during 2011-2012 in Shanghai, China, and obtained parent-reported data regarding childhood atopic eczema using an improved ISAAC questionnaire. We recorded daily concentrations of SO2, NO2, and PM10 throughout the childs lifetime (2006-2012), and calculated period-averaged concentrations for each district where the child lived to represent the childs exposure levels of these pollutants during different periods. In the multiple logistic regression analyses adjusted for potential confounders as well as for the other pollutants in the same periods, childhood atopic eczema was significantly associated with increments of NO2 in the approximate interquartile range (20μg/m3) during gestational period (adjusted OR, 95% CI for eczema lifetime-ever: 1.80, 1.29-2.49; for eczema in the year prior to the survey: 2.32, 1.57-3.43) and during the first year of life (2.00, 1.40-2.84; 2.16, 1.43-3.28). Exposure to elevated NO2 in the first two years, three years and total lifetime, as well as exposure to mixtures containing NO2 in each of these periods, were consistently associated with increased likelihood of childhood eczema. The highest odds ratios were found between exposure to a mixture of SO2 and NO2 during total lifetime (increment: 35μg/m3) and childhood eczema (adjusted OR, 95% CI: 2.80, 1.75-4.48; 3.50, 1.98-6.19). No significant associations were found between childhood eczema and ambient SO2 and PM10 individually or in mixtures. This study indicates that gestational and lifetime exposures to ambient NO2 are risk factors for atopic eczema in childhood. Exposure to ambient SO2 and PM10 may enhance the effect of NO2 exposure on childhood eczema.

Household environmental exposures during gestation and birth outcomes: A cross-sectional study in Shanghai, China

Several studies have reported that certain aspects of the household environments are associated with adverse birth outcomes, but associations have been inconsistent. Few of these studies have been conducted in China. During 2011-2012, we conducted a retrospective cross-sectional study and collected 13,335 parents-reported questionnaires for 4-6-year-olds children in Shanghai, China. We investigated associations of household environmental factors (environmental tobacco smoke (ETS), cooking fuel, dampness, pet-keeping, and home renovation) during gestation with preterm birth (PTB, gestational age<37weeks), low birth weight (LBW, birth weight<2500g), term low birth weight (T-LBW, LBW when the gestational age was ≥37weeks), and small for gestational age (SGA, birth weight<10th percentile of birth weight for gestational age). A total of 4.1% children were premature; 2.9% had LBW and 1.6% had T-LBW; 8.1% were SGA. In the multiple logistic regression analyses, home renovation during gestation was associated with PTB (adjusted odds ratio (OR), 95% confidence intervals (CI): 1.68, 1.11-2.54) and LBW (1.64, 0.99-2.72). Paternal smoking was associated with PTB (1.18, 0.98-1.43). No significant associations were found for SGA. Neither household dampness nor cooking fuel were significantly associated with birth outcomes. For boys, paternal smoking was associated with PTB (1.31, 1.02-1.69); home renovation during gestation was associated with PTB (2.14, 1.27-3.61) and LBW (2.19, 1.09-4.43). Among children whose mothers were ≥34-year-olds during gestation, paternal smoking (1.73, 1.04-2.76) and home renovation during gestation (1.80, 1.18-2.76) was associated with PTB. Our findings demonstrate that home renovation and ETS during gestation may be risk factors for adverse birth outcomes. Associations of these factors with adverse birth outcomes appear to be stronger in boys and among mothers older than 34years during gestation. Home renovation and ETS exposure should be avoided during gestation, especially for pregnancies with male fetuses and older pregnant women.

Associations of urinary phthalate metabolites with residential characteristics, lifestyles, and dietary habits among young children in Shanghai, China

Exposure to household phthalates has been reported to have adverse effects on childrens health. In this paper, we used phthalate metabolites in the first morning urine as indicators of household phthalate exposures and examined their associations with residential characteristics, lifestyles and dietary habits among young children. During 2013-2014, we collected morning urines from children aged 5-10years in Shanghai, China and obtained the related information about analyzed factors in this study by questionnaires. Urinary phthalate metabolites were analyzed by isotope dilution-high performance liquid chromatography (HPLC)-heated electrospray ionization source (HESI) coupled with a triple quadrupole mass spectrometry. ANOVA, the Mann-Whitney or Kruskai-Wallis rank tests, and multivariate linear regression analyses were used to examine the target associations. Ten metabolites of seven phthalates in 434 urine samples were analyzed. The detection rates of eight metabolites (MiBP, MnBP, MEHP, MECPP, MEHHP, MEOHP, MEP, and MMP) were >90%, except for MBzP (51.2%), and MCHP with <10.0% of detection rate was not included in analyses. By multivariate linear regression analyses, factors significantly associated with higher concentrations of metabolites included non-usage household air cleaners (MEP and MEHP), changing the childs pillowcase less than one time a week (DEHP metabolites), dusting furniture in the childs bedroom less than three times a week (MMP and MnBP), using more plastic toys (DEHP metabolites and MEP), often having soft drinks (DEHP metabolites) and candies (MiBP). Our results indicated that phthalate exposures were common among Shanghai children and residential characteristics had less significant associations with urinary phthalate metabolites compared with lifestyles and dietary habits. Using less plastic toys, having less candies and soft drinks, using household air cleaner, as well as frequently changing the childs pillowcase and dusting furniture in the childs bedroom could reduce phthalate exposures among children.

Home dampness-related exposures increase the risk of common colds among preschool children in Shanghai, China: Modified by household ventilation

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

Associations of household renovation materials and periods with childhood asthma, in China: A retrospective cohort study

BACKGROUND Childhood asthma is prevalent in China. However, there is a lack of evidence on whether household renovation, including the materials used and the periods, are associated with the disease. OBJECTIVES To investigate the associations between household decoration materials and renovation periods, and childhood asthma and its related symptoms. METHODS During 2010-2012, a retrospective cohort study was initiated in seven cities of China, and 40,010 children, aged 3-6 years, were recruited. Data on demographics, health status, and home decoration conditions were collected using a parent-administered questionnaire. Two-level (city-child) logistic regression analyses with adjusted odds ratios (AORs) and 95% confidence intervals (CIs) were performed to show the target associations. Sensitivity analysis was performed by stratifying data for children in the southern and northern cities. RESULTS Children whose homes underwent renovation or the addition of new furniture within 1 year before pregnancy, during pregnancy, at age 0-1 year, and after age 1 year had significantly (p < 0.05) higher prevalence of childhood asthma and its related symptoms. The use of solid wood floors and wallpaper had significant associations (cement: AOR, 95% CI: 1.59, 1.17-2.17; lime: AOR, 95% CI: 1.31, 1.00-1.71) with an increased risk of lifetime asthma. Household renovation and the addition of new furniture during pregnancy had significant associations with lifetime asthma (renovation: AOR, 95% CI: 1.23, 1.01-1.51); lifetime wheeze (renovation: AOR, 95% CI: 1.21, 1.05-1.39; furniture: AOR, 95% CI: 1.24, 1.14-1.36), current wheeze (renovation: AOR, 95% CI, 1.21 1.05-1.40; furniture: AOR, 95% CI: 1.23, 1.12-1.34), and current dry cough (renovation: AOR, 95% CI: 1.41, 1.23-1.63; furniture: AOR, 95% CI: 1.28, 1.17-1.41). Similar associations were found between the addition of new furniture during early childhood and lifetime asthma and its related symptoms. Except for the association between lifetime wheeze and flooring materials, the studied associations were generally stronger among children from the northern cities. CONCLUSIONS We confirmed that using cellulose based materials in home decoration and renovation, and adding new furniture during early childhood and pregnancy could be risk factors for childhood asthma. The association between household decoration during early childhood and childhood asthma may be stronger in the northern cities of China.