Study on the method performances for screening and confirmatory analysis of aflatoxin M1 in raw milk according to the mycotoxin regulative requirements

Abstract

Screening and confirmatory methods for aflatoxin M1 (AFM1) analysis were optimized and studied regarding the European Decision 2002/657/EC requirements. The recoveries of AFM1 from the spiked samples at levels between 0.025 and 0.075 μg kg-1 were 99.6-110.3% with precision of 10.5-13.4%, confirming the immunochemical method precision and reliability for intensive surveillance studies. According to the regulatory requirements, for confirmation of the obtained positives from the screening, the reference high-performance liquid chromatographic procedure was evaluated in reference to the performance criteria. The between-day recovery obtained was in the range 67.2-72.8%, and the precision range was 5.4-9.1%. Two hundred and twenty five positives from the screening were subjected to confirmatory analysis. Comparison of the data obtained from the immunoassay and chromatographic method (R2 = 0.764) revealed a slight overestimation of the screening method, but no cases of false-negative determinations occurred.