Then, the analytes present in the adsorbent matrix are desorbed (activated carbon) in a series of 6 monitors with 1 ml of the mixture composed of dichloromethane: methanol (50:50). They were all subjected to mechanical agitation for 10 min, 60 cycles per min. After 15 min resting, extraction of new samples to be injected in the GC was conducted. Table 3 shows the recovery factors obtained.