Gaseous and Particle-bound VOC Products of Combustion Extracted by Needle Trap Samplers

Gaseous benzene, toluene, ethylbenzene and o-xylene (BTEX) were extracted by using the divinylbenzene (DVB) particles (mesh sizes 60-80, 80-100 and 100-120) as sorbents packed in passive needle trap samplers (NTS). This study performed feasibility tests of these self-designed DVB-NTS as diffusive time-weighted average (TWA) samplers and compared extraction efficiency with that of 100 mm polydimethylsiloxane-solid phase microextration (PDMS-SPME) fiber for sampling gaseous and particle-bound volatile organic compounds (VOCs) from burning mosquito coils. Experimental results indicated that extraction rate of NTS is a reliable index in extracting VOCs. Additionally, comparisons of the NTS in extracting BTEX mass showed the NTS packed with the smallest diameters of adsorbent particles (100-120 mesh DVB) were the most effective. The mass of gaseous BTEX extracted by 100 m PDMS-SPME fiber were substantially lower than that extracted by DVB-NTS of all meshes for the 30-min TWA sampling of burning mosquito coils, and NTS packed with 100-120 mesh DVB adsorbed BTEX 50-120 ng BTEX. Particles clogging inside the packed phase of NTS inhibited VOC extraction performance after 3-5 samplings of burning particles, especially NTS packed with small-diameter adsorbents.