Confirmation of trace level residues in the food supply

Abstract

With the recent proliferation of mass spectrometric methods available for the identification and confirmation of various compounds in different environmental matrices, it is timely to address the criteria desirable in a regulatory sample case. The emphasis of this review is on the experimental process of confirmation at concentration levels in the range of low parts per million (ppm) to parts per trillion (ppt). At such levels, various data manipulations or alternate choices of approaching the analytical problem of confirmation must be employed to ensure an acceptable result. The problems experienced when dealing with nanogram levels in analysis are much more complex than when recording a mass spectrum of an ample supply of a reference standard. This review reflects an interpretation of the developing status of confirmation since there does not yet exist "accepted criteria".

Confirmation and Quantitation of Selected Sulfonylurea, Imidazolinone, and Sulfonamide Herbicides in Surface Water Using Electrospray LC/MS

“…[49][50][51][52][53][54][55][56][57] A number of reviews describing the development of criteria for confirmation using GC/MS, LC/MS, and MS/MS have been published. [58][59][60][61] The original guideline of a minimum of three ions for confirmation has been widely adopted. Today, the majority of confirmations reported in the literature have been performed with three or more ions.…”

“…However, a number of factors have been commonly used in the literature as proof for confirmation since Sphon in 1978 48 defined specific requirements for the confirmation of drug residues by GC/electron impact MS. These factors include the matching of the compound retention time with a standard and the presence of three or more characteristic ions with the appropriate relative abundance compared to a standard. − A number of reviews describing the development of criteria for confirmation using GC/MS, LC/MS, and MS/MS have been published. − The original guideline of a minimum of three ions for confirmation has been widely adopted. Today, the majority of confirmations reported in the literature have been performed with three or more ions.…”