Commercially available adsorbents were screened for suitability in the Purge and Trap-Thermal Desorption-GC determination of ethylene. The adsorbents tested were Carbosieve’-SIII, Carboxen’-569, Tenax’-TA, and Chro-mosorb’-106. Parameters investigated include breakthrough volume, thermal desorption efficiency, GC column type, linearity, dynamic range of calibration and detection limit. The breakthrough volume is defined as the volume of carrier gas, as a function of temperature, that makes the analyte compounds elute from the adsorbent bed. Because of a large breakthrough volume and a fast elution time for two of the adsorbent candidates, the purge and trap thermal desorption is able to analyze ethylene at a level of less than 1 ppb (V/V) with a normal gas chromatography-flame ionization detector (GC-FID). Such a low detection limit is useful for following the ethylene production rate at different stages of plant growth and evaluating the efficiency of a waste processing biofilter. The same technique can be applied for analysis of emission of other volatile organic compounds. In this paper, we also included samples of test results for ethylene production rate in living tomato plants.