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I.Introduction45   II.Pesticide Structures and Properties46  III.Extraction and Isolation Methods from Environmental and Food Samples47  IV.LC/MS/MS Analysis of Pesticides53A.  Interfacing Systems53B.  Instrumental Aspects57C.  Optimization of Chromatographic Mass Spectrometric Conditions57    V.Tandem MS Methods59A.  Triple Quadrupole59B.  Quadrupole Ion Trap66C.  Hybrid Quadrupole TOF (Q‐TOF)71    VI.Performance Characteristics of LC‐Tandem MS for Pesticides72   VII.Applications75  VIII.Conclusions80References81 An overview is given on pesticide‐residue determination in environmental and food samples by liquid chromatography/mass spectrometry/mass spectrometry (LC/MS/MS). Pesticides comprise a large number of substances that belong to many completely different chemical groups, the only common characteristic is that they are effective against pests. They still constitute a challenge in MS because there is no collective pathway for fragmentation. A brief introduction to the theory of tandem MS permits a discussion of which parameters influence the ionization efficiency when the ions are subjected to different actions. Emphasis is placed on the different tandem MS instruments: triple and ion‐trap quadrupoles, and hybrid quadrupole time‐of‐flight (Q‐TOF), including advantages and drawbacks, typical detection limits, and ion signals at low concentrations. The instrumental setup, as well as LC and mass spectrometric experimental conditions, must be carefully selected to increase the performance of the analytical system. The capacity of each instrument to provide useful data for the identification of pesticides, and the possibility to obtain structural information for the identification of target and non‐target compounds, are discussed. Finally, sample preparation techniques and examples of applications are debated to reveal the potential of the current state‐of‐the‐art technology, and to further promote the usefulness of tandem MS. © 2003 Wiley Periodicals, Inc., Mass Spec Rev 23:45–85, 2004

Alternaria is one of the major mycotoxigenic fungal genera with more than 70 reported metabolites. Alternaria mycotoxins showed notably toxicity, such as mutagenicity, carcinogenicity, induction of DNA strand break, sphingolipid metabolism disruption, or inhibition of enzymes activity and photophosphorylation. This review reports on the toxicity, stability, metabolism, current analytical methods, and prevalence of Alternaria mycotoxins in food and feed through the most recent published research. Half of the publications were focused on fruits, vegetables, and derived products-mainly tomato and apples-while cereals and cereal byproducts represented 38%. The most studied compounds were alternariol, alternariol methyl ether, tentoxin, and tenuazonic acid, but altenuene, altertoxins (I, II, and III), and macrosporin have been gaining importance in recent years. Solid-liquid extraction (50%) with acetonitrile or ethyl acetate was the most common extraction methodology, followed by QuEChERS and dilutiondirect injection (both 14%). High-and ultraperformance liquid chromatography coupled with tandem mass spectrometry was the predominant determination technique (80%). The highest levels of alternariol and alternariol methyl ether were found in lentils, oilseeds, tomatoes, carrots, juices, wines, and cereals. Tenuazonic acid highest levels were detected in cereals followed by beer, while alternariol, alternariol methyl ether, tenuazonic acid, and tentoxin were found in legumes, nuts, and oilseeds.

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