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Introduction: Studies on the associations between phthalate exposures and respiratory outcomes are limited. We investigated the association of phthalates exposure with pulmonary function and airway inflammation in asthmatic children. Methods: Fifty-six children with asthma living in Seoul Metropolitan Area, Korea aged 6–16 years were enrolled. Their pulmonary function including forced expiratory volume in 1 sec (FEV1) and peak expiratory flow rate (PEFR) were measured, and the fractional exhaled nitric oxide (FeNO) as a marker of airway inflammation was examined repeatedly up to four times during the study period. Urinary levels of mono-(2-ethyl-5-hydroxyhexyl) phthalate (MEHHP) and mono-(2-ethyl-5-oxohexyl) phthalate (MEOHP), metabolites for di-(2-ethylhexyl) phthalate (DEHP), and mono-n-butyl phthalate (MnBP), a metabolite of di-n-butyl phthalate (DnBP), were also measured on the same days. The effects of phthalate metabolites on the respiratory symptoms were analyzed using linear mixed effect models with adjustment for potential cofounders. Results: An increase in phthalate metabolites was associated with a decrease in pulmonary function and an increase in FeNO in asthmatic children. As one natural log-unit (ln-unit) levels of urinary MEHHP and MEOHP increased, FeNO levels on the same day increased by 19.47 ppb [95% confidence interval (CI): 9.28, 29.67] and 17.93 ppb (95% CI: 5.86, 30.01), respectively. An increases in the urinary level of MEHHP, MEOHP, and MnBP by one ln-unit was associated with a decrease in PEFR on the next day by 12.17 L/min (95% CI: 2.59, 21.74), 10.80 L/min (95% CI: 0.29, 21.32), and 13.65 L/min (95% CI: 5.07, 22.24), respectively. Conclusion: Phthalates, especially DEHP, may worsen pulmonary function and airway inflammation in asthmatic children. To control asthma symptoms, exposure to phthalates needs to be avoided. [ABSTRACT FROM AUTHOR]

Introduction: The effects of weather and air pollution on the severity and persistence of atopic dermatitis (AD) are important issues that have not been investigated in detail. The objective of our study was to determine the short-term effects of meteorological variables and air pollution on AD symptoms in children. Methods: We enrolled 177 AD patients with 5 years or younger from the Seoul Metropolitan Area, Korea, and followed for 17 months between August 2013 and December 2014. Symptoms records of 35,158 person-days, including itching, sleep disturbance, erythema, dry skin, oozing, and edema, were obtained. We estimated the effect of meteorological variables including daily mean temperature, relative humidity (RH), diurnal temperature range (DTR), rainfall and air pollutants including particulate matter with an aerodynamic diameter ≤10 μm (PM10), nitrogen dioxide (NO2), and tropospheric ozone (O3) on AD symptoms using a generalized linear mixed model with adjustment for related confounding factors. Results: A 5°C increase in outdoor temperature and a 5% increase in outdoor RH was associated with 12.8% (95% confidence intervals (CI): 10.5, 15.2) and 3.3% (95% CI: 1.7, 4.7) decrease in AD symptoms, respectively, on the same day. An increase of rainfall by 5 mm increased AD symptoms by 7.3% (95% CI: 3.6, 11.1) for the days with <40 mm rainfall. The risk of AD symptoms increased by 284.9% (95% CI: 67.6, 784.2) according to a 5°C increase in DTR when it was >14°C. An increase in PM10, NO2, and O3 by 10 units increased the risk of AD symptoms on the same day by 3.2% (95% CI: 1.5, 4.9), 5.0% (95% CI: 1.4, 8.8), and 6.1% (95% CI: 3.2, 9.0), respectively. Conclusion: Exposure to meteorological variables and air pollutants are associated with AD symptoms in young children. [ABSTRACT FROM AUTHOR]