The condensate was collected by inserting 2 ml of deuterated methanol (MeOD) into the syringe. From the condensate methanol mixture, 600 µl were transferred to a NMR tube for the quantification of ∆ 9 -THC and CBD in a Bruker 400 MHz Ultrashield NMR spectrometer (Bruker, Rheinstetten, Germany). The NMR method was previously described in detail . As a reference sample, the same amount of unvaporized e-liquid was dissolved in 2 ml of MeOD and also prepared for measurement. From each remaining sample solution, which has been obtained from vaporizing the liquids at 0.2 Ω and 200 W, dilutions were prepared for the quantification of ∆ 9 -THC and CBD using a previously described liquid chromatography tandem mass spectrometry (LC-MS/MS) method with the following modifications to improve separation of cannabinoids: separation column Raptor, ARC-18, 2.7 µm, 150*2.1 mm (Shimadzu Deutschland GmbH, Duisburg, Germany). The separation was isocratic with 20% water and 80% methanol, containing 0.1% of formic acid.