Indoor particulate matter levels in school classrooms and its association with asthma and allergic rhinitis in adolescents from Anuradhapura, Sri Lanka

Résumé fourni par la source

Introduction: Indoor air quality significantly affects respiratory health, and particulate matter (PM) is a critical indoor air pollutant. The aerodynamic diameter of PM determines its depth of penetration along the tracheobronchial tree and resultant health effects.Objectives: To assess indoor PM levels in classrooms and their association with asthma and allergic rhinitis symptoms among adolescent children.Method: A descriptive cross-sectional study was conducted in 32 grade 8 classes from 6 selected secondary schools in the Anuradhapura municipal council area, Sri Lanka. Indoor PM levels, relative humidity, temperature, wet-bulb temperature, and dew point were measured using a video particle counter (VPC300, EXTECH®). International Study of Asthma and Allergies in Childhood was used to assess the prevalence of current wheezing, severe asthma and allergic rhinitis.Results: Of the 32 selected classrooms, PM0.3, PM0.5, PM1, PM2.5, PM5 and PM10 levels exceeded recommended levels in 30, 28, 26, 32, 30 and 30 classrooms, respectively. Highest mean counts of PM0.3, PM0.5, PM1.0, PM2.5, PM5.0 and PM10 among the 32 classrooms were 848,362±163,795, 533,648±138,542, 110,297±34,240, 15,634±16,817, 2394±2,284 and 974±211, respectively. The highest mean fine particulate matter level was more than 28 times the approved range. Maximum counts of PM1.0 (176,048), PM2.5 (56,237), and PM10 (2,025) were 20 times, 103 times and 29 times the approved ranges. Relative humidity and air temperature levels exceeded recommended levels in 27 and 32 classrooms, respectively. Dew point and wet bulb temperature ranged from 21.9°C to 31.6°C and 24.0°C to 26.3°C, respectively. The minimum PM0.3 level detected in a classroom showed a positive correlation with the proportion of severe asthmatics in a classroom.Conclusions: Indoor air quality in most classrooms was suboptimal and was significantly associated with severe asthma but not allergic rhinitis or current wheezing.

Ce résumé expose les affirmations des auteurs. BNTIC ne l’interprète pas comme une validation indépendante des résultats.