Infrared Spectrophotometric Method for Analysis of Guthion Insecticide: Collaborative Study

Abstract

A collaborative study on the assay of Guthion (azinphos methyl) has been conducted by 10 laboratories. Data were obtained on a 2 Ib/gal. liquid concentrate and a 50% wettable powder formulation. The procedure specifies extraction and/or dilution followed by infrared absorbance measurement at 654 cm-1. The method has been adopted as official first action.