A sensitive and validated method for determination of T-2 and HT-2 toxin residues in shrimp tissues by LC-MS/MS

Abstract

Accurate analyses of T-2 and HT-2 toxin in aquatic organisms including shrimp are important as these two toxins are increasingly detected in aquatic cereal-based feed. Therefore, the potential for these toxins to enter the human food chain from contaminated fish and shrimp products is very real. A rapid, sensitive, and validated method for simultaneous determination of T-2 and HT-2 toxins was developed using a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method following extraction of the two toxins from shrimp tissues with ethyl acetate. This method is simple in that additional solid-phase extraction is not required to isolate and purify the toxins. LC was performed on an analytical Hypersil GOLD column. The mobile phase consisted of methanol and 5 mM ammonium acetate containing 0.1 % formic acid. The MS/MS ion transitions for both the T-2 toxin (484.20 → 214.87) and HT-2 toxin (442.20 → 214.96) were monitored. And the most intense transition ion product (m/z) of T-2 and HT-2 used for quantification on the SRM mode of a mass spectrometer was 304.95 and 262.91, respectively. The results linearly correlated with coefficients >0.9990. The limits of quantification ranged from 0.02 to 0.51 ng·g−1 and from 0.17 to 4.48 ng·g−1 for T-2 and HT-2, respectively, depending on the shrimp tissue type. The overall extraction recovery for both toxins ranged between 84 and 111 % with RSD values less than 15.0 %, indicative of good replication. Furthermore, the recovery and precision levels were within the predefined limits (≤15 %) at all concentrations. The application of this method to study the accumulation of T-2 toxin in shrimp showed that it can be successfully used to monitor even very low tissue toxin concentrations. Research is in progress to extend this method for the measurement of T-2 and HT-2 in aquatic foods that enter the human food chain.