Fine particles characterization in residential homes located in different microenvironment of India

Aerosol Spectrometer was used for monitoring the indoor and outdoor mass concentration of fine PM2.5, PM1.0, PM0.5 and PM0.25 in homes, located in urban, roadside and rural area of Agra city located in the north central part of India. For chemical characterization samples are collected with medium volume sampler on PTFE filters. The collected filters were extracted in an ultrasonic extractor for the determination of water soluble ions. Concentrations for F-, Cl-, NO3-, and SO42- were determined by ion chromatography. Na+, K+, Ca2+, Ba+, and Mg2+ determined by Atomic Absorption Spectrometer. The trends of particulate mass concentration indoors were rural>roadside>urban and for outdoors were roadside>rural>urban. PM2.5 concentration in our results exceeded WHO guidelines by 8-10 times for outdoor and by 7-9 times for the indoor environment during the collection period. Water soluble species ranged from 60% to 92% (Avg 72%, SD 13%) for PM2.5 total mass. The total sum of ionic concentrations in PM2.5 follow the same trend as that by mass concentration. The average I/O ratios are found to be higher in PM2.5 particles at rural and roadside sites indicating additional sources indoors at these sites.