title: High-Throughput Quantification of Monofluoroacetate (1080) in Milk as a Response to an Extortion Threat.
abstract: As a food defense measure against an extortion threat to poison infant formula with monofluoroacetate, a robust methodology for monofluoroacetate analysis in fluid milk and powdered dairy products was developed and optimized. Critical challenges posed by this situation required that the analytical methodology provide (i) high specificity, (ii) high throughput capable of analyzing thousands of samples of fluid milk per day, and (iii) trace-level detection of 1 ng/g or lower to achieve the maximum residue limit. Solid-phase extraction-purified acetone extracts of fluid milk were derivatized with aniline, and after ultrahigh-performance liquid chromatography using a Kinetex-C18 column packed with 1.3-μm shell particles, the resulting N-phenyl 2-fluoroacetamide could be determined by liquid chromatography-tandem mass spectrometry in a highly specific manner and with a limit of quantification of 0.5 ng/ml. By using 4-(4-chlorophenoxy)aniline as a derivatizing agent, the method could be extended to powdered dairy products with the same limit of quantification. Between January and July 2015, some 136,000 fluid milk samples were tested using this method. This analytical testing of fluid milk formed one element in a larger program of work by multiple agencies to ensure that consumers could continue to have confidence in the safety of New Zealand milk and dairy products.
authors.affiliation: Analytica Laboratories, Ruakura Research Centre, 10 Bisley Road, Private Bag 3123, Hamilton 3240, New Zealand.
authors.forename: Terry P
authors.initials: TP
authors.lastname: Cooney
authors.affiliation: Fonterra Research and Development Centre, Dairy Farm Road, Private Bag 11029, Palmerston North 4442, New Zealand.
authors.forename: Peter
authors.initials: P
authors.lastname: Varelis
authors.affiliation: Fonterra Research and Development Centre, Dairy Farm Road, Private Bag 11029, Palmerston North 4442, New Zealand. justin.bendall@fonterra.com.
authors.forename: Justin G
authors.initials: JG
authors.lastname: Bendall
mesh_terms: D000818:Animals; D002417:Cattle; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D005463:Fluoroacetates / Q000032:analysis*; D005506:Food Contamination / Q000032:analysis*; D057166:High-Throughput Screening Assays / Q000379:methods*; D041943:Infant Formula / Q000737:chemistry*; D008892:Milk / Q000737:chemistry; D012680:Sensitivity and Specificity; D052616:Solid Phase Extraction / Q000379:methods*; D053719:Tandem Mass Spectrometry / Q000379:methods*
chemical_list: D005463:Fluoroacetates; C014815:fluoroacetic acid