Mass Spectrometry for the Analysis of Pesticide Residues and their Metabolites

Despina Tsipi is the Director of Food Safety & Quality Laboratories (including the Pesticide Residues Laboratory) of the General Chemical State Laboratory, Athens, Greece. She holds a B.Sc. in Chemistry and a Ph.D in Photochemistry from the University of Athens, after a doctoral fellowship in NRSC Demokritos. She works in the field of pesticide residues analysis in foodstuffs and environment using hyphenated MS techniques for over 20 years. Between 2003-2006, she joined the Panel of Plant Protection Products and their Residues (PPR-Panel) of the European Food Safety Authority. She is a founding member and current president of the Hellenic Mass Spectrometry Society.Helen Botitsi is the Head of the Pesticide Residues Laboratory, a National Reference Laboratory of EU for pesticide residues analysis in foods of plant and animal origin of the General Chemical State Laboratory, Athens, Greece. She holds a B.Sc. in Chemistry and a Ph.D in Biochemistry from the University of Athens. Her main field of expertise is method development for pesticide and pharmaceutical residues analysis in foodstuffs and environmental samples using GC-MS and LC-MS techniques as well as method validation and quality control.Anastasios Economou is Associate Professor at the Laboratory of Analytical Chemistry, University of Athens, Greece. He holds a B.Sc. in Chemistry from the University of Athens, a M.Sc. and a Ph.D in Analytical Science and Chemical Instrumentation from the University of Manchester. His research interests are focused on the development of electrochemical, spectroscopic and chromatographic analytical methods as well as the development of automated analytical systems.

• List of contributors xiForeword xiiiPreface xv1 Pesticide Chemistry and Risk Assessment 1Despina Tsipi, Helen Botitsi, and Anastasios Economou1.1 Introduction 11.2 Pesticide Chemistry 21.2.1 Historical Perspective 21.2.2 Identity and Physicochemical Properties of Pesticides 21.2.3 Pesticide Classification 41.2.4 Modes of Action (MoA) 51.3 Pesticide Metabolites and Transformation Products 81.3.1 Biotransformation 91.3.2 Environmental Fate 131.4 Risk Assessment 141.4.1 Safety Factors 141.4.2 Ecological Risk Assessment for Pesticides 151.5 Dietary Exposure to Pesticides 171.5.1 Acute Exposure or Short‐Term Intake 181.5.2 Chronic Exposure or Long‐Term Intake 181.5.3 Cumulative Exposure to Multiple Substances 181.6 Pesticide Residues in Food 191.6.1 Maximum Residue Limits 191.6.2 Residue Definition 201.6.3 Reporting of Results 281.6.4 Residue Analysis 28References 292 Legislation, Monitoring, and Analytical Quality Control for Pesticide Residues 35Despina Tsipi, Helen Botitsi, and Anastasios Economou2.1 Introduction 352.2 Food Safety 362.2.1 CAC of Food and Agriculture Organization/World Health Organization 362.2.2 EU Legislation 362.2.3 US Food Regulations 402.3 Water Quality 442.3.1 WHO 442.3.2 EU Water Framework Directive 442.3.3 US EPA Legislation 462.4 Method Validation and Quality Control Procedures for Pesticide Residues Analysis 462.4.1 CAC Guidelines 462.4.2 EU Guidelines: SANCO Document 472.4.3 FDA and EPA Guidelines 48References 503 Advanced Sample Preparation Techniques for MS Analysis 53Yolanda Picó3.1 Introduction 533.2 Conventional Extraction and Cleanup Procedures 543.2.1 LLE 543.2.2 SPE 613.2.3 MSPD 633.2.4 QuEChERS 633.3 Microextraction Techniques 653.3.1 Sorbent‐Based Microextraction Techniques 653.3.2 Liquid‐Based Microextraction Techniques 713.4 Alternative Extraction and Cleanup Procedures 733.4.1 Alternative Energy Sources to Enhance the Extraction 733.4.2 Coupled‐Column Liquid Chromatography (LC/PC, LC/LC Techniques) 793.4.3 Direct Analysis in Real Time 803.5 Conclusions 81References 824 Recent Developments in Gas Chromatography–Mass Spectrometry 91Kaushik Banerjee and Sagar Utture4.1 Introduction 914.2 Advances in GC Separations 914.2.1 Multidimensional and Comprehensive Two‐Dimensional Gas Chromatography 924.2.2 Fast GC 944.2.3 LPGC 954.3 Mass Spectrometric Ionization Techniques 964.3.1 Electron Impact Ionization (EI) 974.3.2 CI (Positive/Negative Modes) 974.3.3 Atmospheric Pressure GC–MS 984.4 Mass Analyzers Interfaced to GC 994.4.1 Quadrupole Mass Analyzer 1004.4.2 Ion Trap Mass Analyzer 1004.4.3 QqQ 1004.4.4 TOF 1024.5 Mass Spectral Libraries and Software Approaches in GC–MS Analysis 1034.6 Matrix Effects in GC–MS Analysis 1064.7 Conclusions and Perspectives 108References 1085 Recent Developments in Liquid Chromatography–Mass Spectrometry: Advances in Liquid Chromatographic Separations and Ionization Techniques/Interfaces 113Alexandros G. Asimakopoulos, Anna Bletsou, Kurunthachalam Kannan, and Nikolaos S. Thomaidis5.1 Introduction 1135.2 Advances in Liquid Chromatographic Separations 1145.2.1 Ultraperformance Liquid Chromatography 1165.2.2 Hydrophilic Interaction Liquid Chromatography 1175.3 Ionization Techniques/Interfaces 1175.3.1 Atmospheric Pressure Ionization Techniques 1185.3.2 Direct Electron Ionization 1215.4 Ambient Ionization Techniques 1225.4.1 DESI, Paper Spray, and Low‐Temperature Plasma Ambient Ionization 1225.4.2 Direct Analysis in Real Time 1245.4.3 Atmospheric Pressure Glow‐Discharge Ionization 1255.5 Summary 125References 1256 Recent Developments in Liquid Chromatography–Mass Spectrometry: Mass Detectors 131Silvia Lacorte, Ana Agüera, Montserrat Cortina‐Puig, and Cristian Gómez‐Canela6.1 Introduction: Mass Spectrometers 1316.1.1 Triple Quadrupole Mass Analyzer 1326.1.2 Quadrupole Ion Trap and Triple Quadrupole Linear Ion Trap 1356.1.3 TOF Mass Analyzer 1386.1.4 Hybrid TOF 1406.1.5 Orbitrap Mass Analyzer 1426.2 Comparison and Complementarities of Different Mass Analyzers in the LC-MS Analysis of Pesticide Residues and their Metabolites 1476.2.1 Dynamic Range 1476.2.2 Scan Rate 1476.2.3 LODs 1486.2.4 Mass Accuracy 1486.2.5 Resolution 1496.2.6 Selectivity 1496.2.7 Mass Range 1506.2.8 Fragmentation 1506.2.9 Identification Capabilities 1506.2.10 Quantification 1516.3 Use of Software Techniques and Spectral Libraries in LC–MS 152References 1547 Matrix Effects in Liquid Chromatography–Electrospray Ionization–Mass Spectrometry 161Helen Stahnke and Lutz Alder7.1 Introduction 1617.1.1 Some Definitions 1617.1.2 Differences between Matrix Effects in GC and LC Methods 1627.1.3 Differences between ESI and Other API Methods 1627.1.4 A Typical Alarming Situation 1637.2 Detection of Matrix Effects 1647.2.1 Calibration in Solvent versus Matrix‐Matched Calibration 1647.2.2 Postcolumn Infusion 1657.2.3 Stable Isotope-Labeled Standards 1667.3 Reduction of Matrix Effects 1667.3.1 Change of LC Conditions 1667.3.2 Change of MS Conditions 1667.3.3 Better Cleanup 1697.3.4 Backflush of LC Columns 1707.3.5 Dilute-and-Shoot 1717.4 Compensation of Matrix Effects 1727.4.1 Internal standards (IS) 1727.4.2 Matrix‐Matched Standards 1747.4.3 Postcolumn Infusion 1747.4.4 Standard Addition 1757.5 An Attempt to Explain Matrix Effects 1767.5.1 Substance Classes Causing Matrix Effects 1767.5.2 Tentative Mechanisms of Matrix Effects 1767.5.3 A Recent View on the Mechanism of Ion Suppression 178References 1808 Liquid Chromatography–Mass Spectrometry Analysis of Pesticide Residues and Their Metabolites in Food Samples 187Ana Lozano, Łukasz Rajski, María del Mar Gómez‐Ramos, Carmen Ferrer, Maria D. Hernando, and Amadeo R. Fernández‐Alba8.1 Introduction 1878.2 Application of LC–QqQ‐MS/MS for the Targeted Analysis of Pesticide Residues and their Metabolites in Food Samples 1898.2.1 Sensitivity 1928.2.2 Linearity 1938.2.3 Matrix Effects 1938.3 Application of LC–Hrms to the Analysis of Pesticide Residues and their Metabolites in Food Samples 1958.3.1 Detection and Identification 1958.3.2 Resolution 1978.3.3 MS/MS Identification 2008.3.4 Sensitivity 2018.3.5 Linearity 2018.3.6 Matrix Effect 2028.4 Data Processing: Automated Database Searches 2028.5 Conclusions and Future Developments 203References 2039 Application of LC–MS/MS and LC–TOF ‐MS for the Identification of Pesticide Residues and Their Metabolites in Environmental Samples 207Imma Ferrer and E. Michael Thurman9.1 Introduction and Occurrence of Pesticides in Environmental Samples 2079.2 State‐of‐the‐Art Techniques for the Identification of Pesticides and their Degradation Products 2089.2.1 LC–MS/MS for the Analysis of Target Compounds 2089.2.2 LC–TOF‐MS and LC–QTOF‐MS for the Analysis of Target and Nontarget Compounds 2099.3 Use of Accurate Mass Tools for the Identification of Pesticide Residues and their Metabolites in Food and Water Samples 2159.3.1 Molecular Features 2159.3.2 Accurate Mass Filters and Isotopic Mass Defect 2209.3.3 Diagnostic Ion Approach 2219.3.4 Accurate Mass Databases 2239.3.5 Accurate Mass Profiling 2259.4 Conclusions 227References 22710 Mass Spectrometric Techniques for the Determination of Pesticide Transformation Products Formed by Advanced Oxidation Processes 231Ioannis K. Konstantinou10.1 Introduction 23110.2 Sample Preparation 23210.3 Hyphenated MS Techniques 23710.3.1 Low‐Resolution Mass Spectrometry: Single‐Stage Quadrupole 23810.3.2 Identification of Pesticide TPs by GC–MS 23810.3.3 Identification of Pesticide TPs by LC–MS 24010.3.4 Identification of Pesticide TPs by the Combination of GC–MS and LC–MS 24110.4 Tandem MS 24110.4.1 Identification of Pesticide TPs by QqQ–MS 24310.4.2 Identification of Pesticide TPs by IT–MS 24410.5 HRMS 24910.5.1 Single Mass Analyzer 24910.5.2 Hybrid HR Mass Spectrometers 25510.6 Conclusions and Perspectives 256References 259Index 263