Sample Preparation Methods for Pesticide Analysis in Food Commodities, Biological and Environment Matrices

Abstract

This chapter focuses on sample preparation procedures for pesticide analysis of food commodities, biological and environmental matrices. This will include pesticides with a broad range of polarity including those that are more amenable to gas chromatographymass spectrometry (organochlorines, organophosphorus pesticides, and pyrethroids) and those commonly analyzed by liquid chromatography-mass spectrometry (carbamates, azole, and strobilurin fungicides, and phenylureas as well as organophosphorus pesticides). QuEChERS (quick, easy, cheap, effective, rugged, and safe) methods or QuEChERS methods with modifications to allow wetting of the dry sample matrix, buffering, changing extraction solvent from acetonitrile to ethyl acetate are examined. Subsequent cleanup using dispersive solid phase extraction or cartridge format solid phase extraction has also been completed to reduce matrix effects. Other solid matrices are frequently extracted with pressurized liquid extraction, microwave assisted extraction, or ultrasonic extraction combined with or followed by dispersive solid phase extraction or solid phase extraction. Particularly for chromatography-mass spectrometry, careful consideration of matrix effects needs to be made when considering the design of the sample preparation procedures. Selection of extraction solvent needs to consider both polarity of target analytes (and their solubility in selected solvents) as well as co-extracted matrix components.

Pesticides and Their Degradation Products Including Metabolites: Chromatography-Mass Spectrometry Methods

“…Acephate 136 [10] 136→42, 136→94 [3] Aspon 211, 253 [1] 378→210, 378→115 [7] Azinphos-methyl 160→105, 160→132 [3] 132→104 [6] Azinphos-ethyl 160→105, 160→132 [3] 132→04 [6] Bromfenvinphos-methyl 295→295 [5] Bromfenvinphos-ethyl 267→159 [5] Bromophos-ethyl 359→303, 359→331 [3,6] 359→303 [5] Bromophos-methyl 331→286, 331→316 [3,6] 331→331 [5] Carbofenothion 157, 342 [1] 342→157, 342→143 [7] Pesticides…”

“…Chlormefos 234→121, 234→154 [3] 243→121 [5] 235→171, 235→199 [6] Chlorphenvinphos 267→159, 323→267 [3] 323→267 [5] 267→159 [6] Chlorpyrifos-methyl 286, 125 [1] 321→268, 321→208 [7] 286 [10] 286→136, 286→241 [3] 286, 288, 125 [17] 286→93 [5] 286→208, 286→286 [6] Chlorpyrifos-ethyl 97, 197 [1] 349→208, 349→40 [7] 199 [10] 314→258, 314→286 [3,6] 97, 197 [11] 314→258 [5] Coumaphos 362 [10] Cyanofenphos 185→157, 157→110 [3] 157→139, 157→110 [6] Demeton-o 88, 60 [11] Diazinon 137, 179 [1] 304→179, 304→137 [7] 304 [10] 304→137, 304→179 [3] 137, 304 [11] 304→179 [5,6] 287, 302, 288 [17] Diazinon-d 10 314 [1] 314→185 [7] Dichlofenthion 223, 97 [1] 314→223, 319→81 [7] 279→222, 279→251 [3] 279→223 [5] 279→223, 279→251 [6] Dichlorvos 185 [10] 185→93 [5] 221→141, 221→145 [6] Dimethoate 125 [10] 230→199 [6] 87, 125 [11] 87, 93, 125…”

“…Dyfonate 109, 137 [1] 246→137, 246→109 [7] Ethion 231, 97 [1] 384→231, 384→203 [7] 231, 384 [11] 231→175, 231→203 [3] Ethoprophos 158→97, 158→114 [3] 158→97 [5] 243→131, 243→173 [6] Fenamiphos 303→154, 303→180 [3] Fenchlorphos 125, 287 [1] 320→285, 320→204 [7] 285→270 [5] Fenitrothion 277, 125 [1] 277→260, 277→109 [7] 109, 125 [11] 260→109, 260→125 [3] 277→260 [5] 260→125 [6] Fenthion 278, 125 [11] 278→125, 278→245 [3] 278→109 [5] 278→135 [6] Fonophos 246→109, 246→137 [3] 246→137, 246→109 [6] Leptophos 171, 377 [1] Malathion 173, 125 [1] 173→ 99 [5] 173, 125, 93 [17] 173→127 [6] 93, 125 [11]…”

Microwave‐assisted extraction in closed vessel in food analysis

“…Several solvents and mixtures have been tested, such as hexane and acetone [108,109], acetonitrile [110][111][112], and acetonitrile/acetone [107]. In particular, the latter (1/1 v/v) succeeded in the efficient extraction of 72 pesticides from 35 different matrices [107], while acetonitrile alone was proven suitable for the combined extraction of pesticides and mycotoxins (total of 46 analytes) in a single procedure from apple [111] providing comparable performances with the quick, easy, cheap, effective, rugged, and safe procedure but is a simpler workflow.…”