Background The prevalence of atopic dermatitis (AD) dramatically increased over these years and environmental factors were considered as potential contributors towards these trends. Objective This study aimed to explore several major environmental exposures, including air pollution, temperature and relative humidity, in order to identify potential modifiable risk factors and their interactive effects on AD. Methods We applied a bivariate response surface model and stratification model based on time‐series Poisson generalized additive models to examine the interactive effects of air pollution and meteorological factors on AD. Results A total of 64 987 outpatient visits for AD were recorded from 1 January 2013 to 31 December 2017. Interactive effects were found between air pollutants and meteorological factors. Enhanced positive associations between pollutants and outpatient visits for AD were found at the highest quartile temperature level. A 10 μg/m3 increase in PM2.5, PM10, NO2 and SO2 were associated with 0.42% (95% CI: 0.16–0.67%), 0.34% (95% CI: 0.15–0.54%), 1.11% (95% CI: 0.38–1.84%) and 1.06% (0.21–1.93%) increase in outpatient visits for AD at the highest quartile temperature level. Conclusion That effects of air pollutants on AD can be modified by meteorological factors, with enhanced effects on hot days.

From the study we concluded that the skin types of the investigated Chinese females are principally type III (more than 70%), and then type II and type IV. The different ways of answering the questionnaire did not affect the results remarkably. The measurements of photobiology parameters confirmed that there is a certain correlation between skin types and MED or MPPD determined in this group of volunteers.

Different to capsaicin, phenoxyethanol did not downregulate the expression of TRPV1 in HaCaT cells, suggesting that different regulatory mechanisms may exist for capsaicin and phenoxyethanol. Our experiments demonstrated that phenoxyethanol induces skin misperception and uncomfortable skin sensations like itching and burning comparable to capsaicin via activating TRPV1. The stimulation was inhibited by blocking TRPV1 with ID1609. The present data strengthened hitherto studies that TRPV1 plays a critical role in sensitive skin.

Our observations indicate that skin sensitivity differs considerably between women from different parts of China and South Korea. We recommend that these differences be considered during the development of cosmetic products in these countries.