Dust Mites Exposure And Health Assessment In Tianjin University Dormitories

Dust mite allergens may cause asthma and allergy,which has attracted more and more attention.The enhancement of building airtightness increases indoor humidity,which provides favorable conditions for the breeding of dust mites.It is the significance of this study to explore whether the exposure to dust mites affected by built environment and lifestyle in northern China,and whether dust mites have become an "man-made" public health problem in Chinese homes.The dormitory is a special kind of residential building with small space and high density of occupants.This study is carried out in university dormitories in Tianjin.The study used questionnaires to survey college students’ health status and dormitory environmental conditions.We conducted environmental measurements and collected dust samples from 239 representative dormitory rooms.Enzyme-linked immunosorbent assay(ELISA)method was used to detect the concentration of Der f 1,the first allergen of dust mites.We found that the median concentration of dust mite allergen Der f 1 in Tianjin university dormitories was 91.0 ng/g,with the minimum of 51.0 ng/g,and the maximum201.0 ng/g.The associations of dust mite allergen exposure with environmental parameters and life styles were analyzed,and it was found that there was a positive association of dust mite allergen concentration with temperature and relative humidity.Ventilation rate was negatively correlated with the concentration of dust mite allergens.In rooms with suspected damp problems,the concentration of house dust mite was significantly higher than those in rooms with no dampness problems.In multivariable regression model,with 1°C increment in temperature,the concentration of dust mite allergens increased by 2.616 ng/g;for every 1% increase in relative humidity,the concentration of dust mite allergens increased by 0.415 ng/g;suspicious humidity increased the concentration of dust mite allergens by 9.340 ng/g.Logistic regression analysis was used to explore the relationship between dust mite allergen Der f 1 exposure and allergic diseases.It was found that when the concentration of dust mite allergen > 97.0 ng/g,the odds ratio of diagnosed eczema reached 2.00;2.47 for rhinitis.Furtherly,we used integrated machine learning algorithm XGBoost to predict exposure level of dust mite allergen indoors.The prediction showed that relative humidity played the most important role in predicting the exposure level of dust mites,followed by temperature,while human behavior have less influence on house dust mite exposure in the prediction model.