Ozone-initiated VOC and particle emissions from a cleaning agent and an air freshener: risk assessment of acute airway effects.

Emissions of volatile organic compounds and ultrafine particles from a kitchen cleaning agent (cream) and plug-in air freshener were investigated in a 20 m(3) walk-in climate chamber at low (~5 ppb) and high ozone (~50 ppb) test concentrations and 0.6 air exchange rate. The products emitted terpenes, inter alia limonene, dihydromyrcenol, geraniol, linalool, and glycol ethers. The ozone-initiated reaction products of these compounds were measured by air sampling on Tenax TA followed by thermal desorption GC-MS and air sampling on DNPH cartridges followed by liquid extraction and HPLC-UV analysis. Particle formation was monitored simultaneously. A number of oxygenated and poly-oxygenated reaction products were identified and risk assessed for acute airway effects: formaldehyde, acetaldehyde, acetone, 4-acetyl-1-methylcyclohexene, 6-methyl-5-heptene-2-one, 3-isopropenyl-6-oxo-heptanal, and 4-oxo-pentanal. These compounds generally increased initially at the high ozone concentration, while the terpenes decayed, concurrent with their consumption of ozone. At high ozone concentration, the plug-in air freshener resulted in concentrations of formaldehyde and 4-oxopentanal that may give rise to concern about sensory irritation and airflow limitation, respectively. At high ozone concentration, the kitchen cleaning agent and air freshener resulted in peak particle mass concentrations at 81 μg/m(3) (8.5×10(5) #/cm(3)) and 24 μg/m(3) (2.3×10(4) #/cm(3)), respectively. At low ozone concentration, the particle concentration peaked at 4 μg/m(3) (1.0×10(5) #/cm(3)) after the application of the kitchen cleaning agent, while no increase was observed for the air freshener. The particles, in view of their organic composition and concentration, are not considered to cause acute airway effects. Testing under realistic conditions that mimic user pattern behavior is warranted to obtain acute and longer-term exposure data at realistic indoor ozone concentrations.