title: Characterization of polyoxyethylene tallow amine surfactants in technical mixtures and glyphosate formulations using ultra-high performance liquid chromatography and triple quadrupole mass spectrometry.
abstract: Little is known about the occurrence, fate, and effects of the ancillary additives in pesticide formulations. Polyoxyethylene tallow amine (POEA) is a non-ionic surfactant used in many glyphosate formulations, a widely applied herbicide both in agricultural and urban environments. POEA has not been previously well characterized, but has been shown to be toxic to various aquatic organisms. Characterization of technical mixtures using ultra-high performance liquid chromatography (UHPLC) and mass spectrometry shows POEA is a complex combination of homologs of different aliphatic moieties and ranges of ethoxylate units. Tandem mass spectrometry experiments indicate that POEA homologs generate no product ions readily suitable for quantitative analysis due to poor sensitivity. A comparison of multiple high performance liquid chromatography (HPLC) and UHPLC analytical columns indicates that the stationary phase is more important in column selection than other parameters for the separation of POEA. Analysis of several agricultural and household glyphosate formulations confirms that POEA is a common ingredient but ethoxylate distributions among formulations vary.
authors.affiliation: United State Geological Survey, 4821 Quail Crest Place, Lawrence, KS 66049, USA; Department of Chemistry, University of Kansas, 1251 Wescoe Hall Drive, Lawrence, KS 66045, USA.
authors.forename: Daniel
authors.initials: D
authors.lastname: Tush
authors.forename: Keith A
authors.initials: KA
authors.lastname: Loftin
authors.forename: Michael T
authors.initials: MT
authors.lastname: Meyer
mesh_terms: D000588:Amines / Q000737:chemistry*; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D005223:Fats / Q000737:chemistry*; D005998:Glycine / Q000031:analogs & derivatives* / Q000737:chemistry; D006540:Herbicides / Q000737:chemistry*; D011092:Polyethylene Glycols / Q000737:chemistry*; D013501:Surface-Active Agents / Q000737:chemistry*; D053719:Tandem Mass Spectrometry / Q000379:methods*; D000097797:Glyphosate
chemical_list: D000588:Amines; D005223:Fats; D005998:Glycine; D006540:Herbicides; D011092:Polyethylene Glycols; D013501:Surface-Active Agents; D000097797:Glyphosate; C013698:tallow
keywords: Adjuvant; Glyphosate; Inert ingredient; Mass spectrometry; Polyoxyethylene tallow amine; Ultra-high performance liquid chromatography