Indoor and oudoor relationship of particle with different size at an apartment in Ha Noi: Mass concentration and repiratory dose estimation

Abstract

This paper presents data on the size distribution and concentration of particulate matters (PM0.1, PM0.5, PM1, PM2.5, PM10, TSP) in indoor and outdoor air at a residential apartment in two seasons (winter and summer) in Ha Noi, Viet Nam. These particles with different sizes were taken by 5 stage impactors (Nano sampler 3182, KINOMAX). Daily average concentrations of coarse particles (PM10) and fine particles (PM2.5) indoors and outdoors exceeded the WHO recommended values. In winter, the concentrations of PM0.5, PM1, PM2.5, PM10 and TSP are higher than in summer. However, concentrations of PM0.1 (NP) remains negligible change between two seasons. The indoor NP accounts about 8 % and 17 % of fine particles (PM2.5) and 7 % and 12 % of coarse particles (PM10) in winter and summer, respectively. The indoor fraction for fine particles (PM0.5, PM1 and PM2.5) have better infiltration than coarse sizes (PM2.5-10, PM10 and TSP), except for NP in summer. Moderate correlation between wind speed (Ws) and PM concentration is found, whereas precipitation (Pr), relative humidity (RH) and temperature (T) correlate with PM concentrations with different sizes weakly. Strong correlations between particles with different sizes are also found in indoors and outdoors (r = 0.73 - 0.98). Household activities like cooking, cleaning and smoking are attributable to elevate the indoor NP. The Monte Carlo simulation shows that highest estimated dose is observed in the age group (over 60 years) and age group (0 - 3 years) suffers the lowest dose, which has implications in the adverse health effects for sensitive groups. Sensitive analysis finds the concentration of particles to be the most influencing factor on inhalation dose estimation.