|Title||Secondary organic aerosol from ozone-initiated reactions with terpene-rich household products|
|Publication Type||Journal Article|
|Year of Publication||2008|
|Authors||Coleman, Beverly K., Melissa M. Lunden, Hugo Destaillats, and William W. Nazaroff|
|Secondary Title||Atmospheric Environment|
|Keywords||aerosols, indoor and outdoor, cleaning products, condensation, environmental chemistry, exposure & risk group, indoor air quality, indoor environment department, limonene, nucleation, ozone, secondary organic aerosol, size distribution, terpenes|
We analyzed secondary organic aerosol (SOA) data from a series of small-chamber experiments in which terpene-rich vapors from household products were combined with ozone under conditions analogous to product use indoors. Reagents were introduced into a continuously ventilated 198 L chamber at steady rates. Consistently, at the time of ozone introduction, nucleation occurred exhibiting behavior similar to atmospheric events. The initial nucleation burst and growth was followed by a period in which approximately stable particle levels wereestablished reflecting a balance between new particle formation, condensational growth, and removal by ventilation. Airborne particles were measured with a scanning mobility particle sizer (SMPS, 10 to 400 nm) in every experiment and with an optical particle counter (OPC, 0.1 to 2.0 µm) in a subset. Parameters for a three-mode lognormal fit to the size distribution at steady state were determined for each experiment. Increasing the supply ozone level increased the steadystatemass concentration and yield of SOA from each product tested. Decreasing the airexchange rate increased the yield. The steady-state fine-particle mass concentration (PM1.1) ranged from 10 to > 300 µg m-3 and yields ranged from 5% to 37%. Steady-state nucleation rates and SOA mass formation rates were on the order of 10 cm-3 s-1 and 10 µg m-3 min-1, respectively.