Indoor, Outdoor, and Personal Exposure to Nitrogen Dioxide Comparing Industrial Complex Area With Country Area

Abstract

O-31A6-2 Background/Aims: Indoor air quality can be affected by indoor sources, ventilation, decay, and outdoor levels. Various indoor and outdoor combustion sources produce nitrogen dioxide (NO2), which is a by-product of high temperature fossil fuel combustion. Especially, the presence of gas ranges and smoking have been identified as major factors contributing to indoor NO2 exposures. In this study, we compared an industrial complex area with a country area by assessing the personal exposure to NO2 with measurements of indoor and outdoor NO2 levels in residences and by house characteristics and questionnaire. Methods: Residential indoor and outdoor NO2 concentrations and personal NO2 exposures were measured for 90 participants in industrial complex area and 30 participants in country area, respectively. Questionnaires related personal life-style and house characteristic were administrated. All measurements were used passive air sampler. Results: Personal exposure concentrations were significantly correlated with indoor NO2 concentrations of residences in both the industrial complex area and the country area with correlation coefficients of 0.561 and 0.664, respectively, compared to outdoors. Multiple regression analysis indicated that indoor NO2 levels in residences were only affected by outdoor levels (P = 0.000) despite higher indoor sources such as smoking. Conclusion: This study is suggested that outdoor air quality as well as indoor air quality should be considered in the reduction of the personal exposure to air pollutants.