AGRO 85 |
| Source and ambient air sampling techniques are seldom validated for the variability in the air matrix. Relative humidity (RH) affects both field sampling and analysis of air samples. The objectives of this study were to determine the effect of RH on the recovery and analysis of agricultural odorants using various sorbent materials. Test atmospheres were generated at ambient temperatures, variable RH (25, 50, and 80%) and variable sample volumes (2, 4, 8, 12 and 24 L of air). A custom designed sorbent tube containing Carbotrap X sorbent material performed best with quantitative recovery of all compounds at all RHs and sampling volumes tested. Tenax sorbent tubes gave quantitative results for all compounds except acetic acid. Sorbent tubes with carbon molecular sieve (CMS) material performed poorly at both 50 and 80% RH. Water management techniques such as heating sorbent tubes during sampling and dry-purging of sorbent tubes after sampling improved both analysis and sample recovery. |
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Agricultural Impacts on Air Quality
8:30 AM-12:00 PM, Tuesday, 12 September 2006 San Francisco Marriott -- Salon 2, Oral
Division of Agrochemicals |