identification of degradation products by adopting GC or HPLC/MS techniques

The persistence of pesticides and drugs in products destined to human consumption are of great concern, in particular because of their potential carcinogenic character. However, often the transformation products formed through degradation processes possess higher toxicity than the parent compounds. It is then of primary importance not only to achieve their abatement (through purification procedures), but also to detect and identify the formed by-products, in order to evaluate their formation kinetics, stability and toxicity. For this purpose, in the present review we will study in depth the transformation pathways followed by molecules belonging to different classes of compounds, i.e pesticides, drugs and dyes and their derivatives in photo-assisted, environmental and biological studies, where they have been identified and characterized by means of hyphenated techniques. Particular attention will be paid to degradation simulating models, such as the photocatalytic process on titanium dioxide.