Direct Analysis Mass Spectrometry

Department of Chemistry, University of Canterbury, PB 4800, Christchurch 8140, New Zealand e-mail murray.meewan eanterbury.ac.nz 

Fujii (ed.), lon/Molecule Attachment Reactions Mass Spectrometry, 

To aid in a comparison of the ways the different techniques have been apphed to monitor volatiles, a short commentary is presented at the end of the discussion of each method summarizing their applications mainly in three different areas environment, food science, and medicine/health. The importance of VOCs to each of these areas is briefly summarized next. 

VOCs have a very important role in the atmosphere. They are emitted by natural and anthropogenic processes and their presence and distribution can have a marked influence on the environment. In the troposphere, VOCs from anthropogenic sources play a major role in the formation of photochemical smog. However, biogenic VOCs (B VOCs) from the world s forests and oceans dominate over VOCs from anthropogenic sources except in the densely populated areas. The role of VOCs in the workplace environment is another growing area of interest. In recent times, there has been a concerted effort in the application of analytical techniques that can directly monitor VOCs in the environment, that are easy to apply and that are both fast and accurate. 

VOCs also have an influential role in food science and technology. They are present in foods and drinks and their presence is intimately involved in aroma and flavor. Both of these factors influence the choiee and preference of consumers. Further, VOCs emitted by foods can provide evidence of the shelf life of a product, of the ripening stage, and whether product adulteration has occurred. The human olfactory threshold can be as low as the pptv range for key aroma compounds, so sensitive analytical techniques are required for interrogatioa 

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