Analytical mass spectrometry of herbicides

I. Introduction 2 II. Scope of Information Within Each Herbicide Category 3 III. Herbicides by Category 4 A. Aliphatic Carboxylic Acids, Esters, and Salts 4 B. Amides, Including Chloroacetanilides 4 C. Aminoacids and Derivatives 5 D. Benzoic and Phthalic Acids, Esters, and Salts 6 E. Benzonitriles 7 F. Cyclohexanediones 7 G. Dinitrophenylamines (Dinitroanilines) 7 H. Diphenyl Ethers 8 I. Imidazolinones 9 J. Miscellaneous Heterocyclics 10 K. Phenols 11 L. Phenoxycarboxylic Acids, Esters, and Salts 12 M. Pyridines 13 N. Pyridazines 14 O. Quaternary Ammonium Salts 15 P. Sulfonylureas 16 Q. Sulfonamides and Other Sulfur Compounds 16 R. Thiocarbamates and Carbamates 19 S. Triazines and Related Compounds 19 T. Triazoles 20 U. Ureas 21 References 22 Herbicides are chemical substances that are applied to agricultural soils, gardens, lawns, or plants to destroy or to prevent the growth of undesirable vegetation. The herbicides included in this review are generally synthetic organic compounds that are ingredients in commercial herbicide products that were designated active during late 2002 in the U.S. Environmental Protection Agency's database of registered and canceled pesticide products. The compounds are organized into 21 categories according to their general chemical structures or a common structural group. The herbicides in each category are discussed in terms of their structures, their database electron ionization mass spectra, and their amenability to separation and measurement with gas chromatography, reversed‐phase liquid chromatography, and capillary electrophoresis combined with mass spectrometry. Ionization techniques that are considered here are mainly electron ionization, electrospray, and atmospheric pressure chemical ionization. Sixty‐six references are provided to herbicide reviews, and to the recent herbicide analytical chemistry and mass spectrometry research literature. © 2003 Wiley Periodicals, Inc., Mass Spec Rev 23:1–24, 2004