Development, Optimization, and Validation of the HS-SPME/GC-MS Method for the Residual Determination of Menthol in Fish

In this study, the development, validation, and residual determination of the menthol anesthetic in fish fillets, cultivated in the pisciculture station of the Federal University of Lavras. The fish were submitted to anesthesia with menthol in different concentrations (50, 75, 100, 125, and 150 μg mL−1) and slaughtered at the times of 0, 12, 24, and 48 h after anesthesia. The objective of the study was to detect traces of anesthetic and to determine the time required for clearance of menthol from animal tissue, stipulating a residual time for elimination of contamination. The headspace solid-phase microextraction (HS-SPME) technique coupled with gas chromatography and mass spectrometry (GC-MS) was applied to residual determination. In order to optimize the methodology, the central composite design (CCD) was employed and, analyzing the obtained response surfaces, it was verified that the optimal working condition was 3 g of salt, 20 min of extraction, and a temperature of 50 °C. The proposed method was validated by obtaining the limits of detection (LD) and quantification (LQ) of 0.015 and 0.046 μg kg−1, respectively, precision and accuracy within the acceptable. The methodology was applied for the residual determination of menthol in fish from tilapia species, in different stages of anesthesia, with a residual period of 48 h for total elimination of this compound in fish tissues. With the obtained results, it is verified that the methodology developed using HS-SPME was efficient for determination of menthol in fish tissues.