Non-Targeted Analysis of Carbofuran and Related Compounds in Commercial Formulations and Animal Tissue

Recently, some cases of intentional animal poisoning using Carbofuran (CF) occurred in the Czech Republic, although CF is no longer available in the EU market. The present study describes a novel non-targeted analysis (NTA) workflow developed to possibly characterize 13 CF formulations from various sources to be certainly identified in real samples. Furthermore, a detection and quantification method for CF was developed for analyzing three animal samples, obtained from dead animals. The analyses were con-ducted using the liquid electron ionization (LEI) interface coupled with a quadrupole time-of-flight (QTOF) mass spectrometer, allowing the simultaneous characterization of the formulation's volatile and low-volatile fractions. Almost all compounds detected in the different formulations were identified by comparing the experimental spectra with the NIST library at high probability values (95–99.38%). Determination of molecular ions, fol-lowed by MS/MS analysis, was performed to confirm compound identities at a high level of confidence. The quantification method for CF was successfully validated, showing neg-ligible matrix effects (107%). CF was detected in two out of the three real samples. Only 3-keto-carbofuran was detected in one of the real samples; without any other marker, it was not possible to identify the specific formulation used in the three poisoning cases.