Photo ionisation-time of flight mass spectrometry (PI-TOFMS) has been established for on-line analysis of complex gas mixtures. Cigarette smoke, e cigarette vapour and the vapour of tobacco heating products provide good examples for such complex gas mixtures. Many toxicants, such as butadiene, acetaldehyde, naphthalene, phenol or polycyclic aromatic hydrocarbons (PAH), can be detected with single puff-resolution in the smoke or vapour of smoking/vapour products.

Vacuum PI-MS can be divided into SPI (Single-Photon-Ionization) ionizing a wide range of organic molecules and REMPI (Resonance-Enhanced-Multi-Photon-Ionization) focusing primarily on aromatic structures. Especially the more sophisticated complementary use of SPI and REMPI can access a new information range.

By focusing the sampling on the origins of substance release or formation it is possible to achieve temporal and spatial resolved analysis of released gas mixtures. This allows, for example, to obtain access into the burning zone of a cigarette with a temporal resolution of 0.1 seconds and a spatial resolution of 0.5 mm.

If a sum information of a whole puff is sufficient, the substance identification and quantification can be improved by using a fast GC approach. A single puff can be collected on a column to analyse it in the delay between two puffs. Depending on the used puff regime, the GC parameters and its separation capabilities can be optimized.

Various smoking/vaping products, ranging from conventional cigarettes to tobacco heating products and e cigarettes, were investigated using PI based MS approaches. Also, semi-legal THC containing smoking products such as joints were investigated on a puff resolved basis.

In summary, the release of desired active compounds (e.g. nicotine or Δ9-THC) and undesirable HPHCs (harmful or potentially harmful compounds) is related beyond the product category to a wide set of parameters such as puff regime, environmental conditions and technical parameters. The puff resolved release profiles enable a reliable understanding of release and reaction pathways.