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This study was performed to evaluate factors affecting desorption of organic solvents collected on charcoal tube and to find out the optimum condition. Desorption efficiency for polar analyzes was improved whets several polar desorption solvents such as methanol, dimethylformamide(DMF), 2-(2-butoxyethoxy)ethanol were added to carbon disulfide(CS₂). The best improvement was achieved when 10% dimethylformamide(DMF) in CS₂ was used as desorption solvent. During storage of polar analyzes, recovery was greatly reduced. Especially, the recovery of cyclohexanone was decreased to 18.1% after a month storage at 34℃. After two weeks storage, recovery of polar analyzes was sharply decreased. Water adsorbed on charcoal interfered the recovery of polar analyses but didn´t interfere that one of nonpolar solvent, toluene. When 10% DMF in CS₂ was used as desorption solvent, the effect of water on recovery was decreased, comparing with CS₂. Desorptian efficiency increased when analyse loading increased, and usage of 10% DMF in CS₂ decreased the loading effect. Increasing volume of desorption solvent was not effective to improve desorption efficiency of analyses when 10% DMF was used. Continuous shaking and sonication is not helpful to increase the desorption efficiency of analyses except cyclohexanone using 10% DMR When silica gel used as adsorbent, methanol was better desorbent than dimethylsulfoxide. Analyzes adsorbed on silica gel showed high recovery in low concentration and less affected by humidity. On the basis of this study, the following conclusions have been drawn. To improve the recovery of polar organic materials in air samples, it is necessary to analyze samples as soon as possible after they were collected. Otherwise, samples must be stored at law temperature. Using two components of desorpton solvents, such as 10% DMF in CS₂, the effects of loading and humidity decreased for polar analyses such as methyl ethyl ketone and methyl isobutyl ketone. When work place has high humidity with low concentration of polar organic solvents, silica gel can be used as adsorbent, because it produces quantitative recovery for polar analyses at this condition. But it should be noted that high humidity makes breakthrough easy in silica gel samples.
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