AAAR 32nd Annual Conference
September 30 - October 4, 2013
Oregon Convention Center
Portland, Oregon, USA
Abstract View
Ultrafine Particles Emitted from Scented Markers
Cha-Chen Fung, Shi Shu, YIFANG ZHU, UCLA
Abstract Number: 334 Working Group: Indoor Aerosols
Abstract Recent studies found an increase in ultrafine particles (UFPs diameter < 100 nm) concentration inside classrooms during art activities. Art products (e.g. scented markers) containing ozone reactive terpenes are possible sources. Experiments using scented markers were conducted inside a stainless steel chamber with air sample ports and fans to control air exchange rate and mixing. Ozone was supplied to the chamber from a UV lamp ozone generator. A scented marker was used to color an area of 24 cm by 18 cm on a sheet of A4 paper inside the chamber via a glove port while UFP number concentration, size distribution, and ozone concentrations were measured. Twelve different scents from three brands of markers were tested and only the lemon scent from one brand produced UFPs. Calculated emission rates ranged from 2.4×10$^6 – 5.7×10$^7 particles/second. Particle size measurements revealed unimodal distributions in the range of 20 – 30 nm. Experiments at decreasing ozone concentrations showed a critical point (50 ppb), below which no UFPs were detected above background. Model simulation revealed that drawing with the lemon-scented marker emitted ozone-reactive VOCs, most likely limonene, in the order of 10 - 100 microgram, which yielded in the same order of magnitude of secondary organic aerosols (SOA). These findings suggest that not all scented markers contain reactive terpenes, and substituting products can reduce children’s exposure to UFPs.