The limit of detection(LOD), pooled coefficient of variation(pooled CV), desorption dffciency(DE), and stability after desorption by pre-treatments was compared and evaluated for analyzing the Ethylene oxide(EO) sampling on HBr-coated Charcoal tube, The results were as follows:
1. The EO´s LOD was 2,483ug/sample when using the desorptin solvent, benzene : CS2(99:1), and 1.919ug/sample after using DMF. The result of the sample that passed DMF desorption and was derivativized was 1.301ug/sample.
2. EO´s pooled CV was 0.00503 when using the solvent benzene:CS(99:1), after desorption with DMF, the result was 0.00329, and the result of those derivativized by DMF desorption was 0.00514.
3. EO´s DE using the solvent benzene:CS(99:1) was 92.13%, atter desorption with DMF, it was 102.75%, and the result of those studied after being derivativized by DMF desorption was 96.47%.
4. EO´s stability for the sample with the solvent benzene:CS(99:1), comparing result of next-day analysis to same-day was 96.81% after desorption was 95.69% These results were in accordance with the less than 5% given by OSHA methoc 50.
In conclusion, when pre-treatment of the EO in the HBr=coated charcoal, analyzing immediately after desorption by DMF is more simple, precise, and efficient than other analyzing methods, and the stabiity of the sample 24 hours after desorption was alst established.
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