Evaluation of distribution of emerging mycotoxins in human tissues: applications of dispersive liquid-liquid microextraction and liquid chromatography-mass spectrometry

Abstract

In this work, a complete study of the distribution of emerging mycotoxins in the human body has been carried out. Specifically, the presence of enniatins (A, A(1), B, B(1)) and beauvericin has been monitored in brain, lung, kidney, fat, liver, and heart samples. A unique methodology based on solid-liquid extraction (SLE) followed by dispersive liquid-liquid microextraction (DLLME) was proposed for the six different matrices. Mycotoxin isolation was performed by adding ultrapure water, acetonitrile, and sodium chloride to the tissue sample for SLE, while the DLLME step was performed using chloroform as extraction solvent. Subsequently, the analysis was carried out by high-performance liquid chromatography coupled to tandem mass spectrometry (HPLC-MS/MS). The proposed method allowed limits of quantification (LOQs) to be obtained in a range of 0.001-0.150 ng g(-1), depending on the tissue and mycotoxin. The precision was investigated intraday and interday, not exceeding of 9.8% of relative standard deviation. In addition, trueness studies achieved 75 to 115% at a mycotoxin concentration of 25 ng g(-1) and from 82 to 118% at 5 ng g(-1). The application of this methodology to 26 forensic autopsies demonstrated the bioaccumulation of emerging mycotoxins in the human body since all mycotoxins were detected in tissues. Enniatin B (ENNB) showed a high occurrence, being detected in 100% of liver (7-±-13 ng g(-1)) and fat samples (0.2-±-0.8 ng g(-1)). The lung had a high incidence of all emerging mycotoxins at low concentrations, while ENNB, ENNB(1), and ENNA(1) were not quantifiable in heart samples. Co-occurrence of mycotoxins was also investigated, and statistical tests were applied to evaluate the distribution of these mycotoxins in the human body.