engleski

Application Of A Multi-Biomarker LC-MS/MS Method For Mycotoxin Exposure Assessment

Humans can be exposed to multiple mycotoxins at the same time, resulting in acute or chronic and potentially synergistic effects. Hence, there is a demand for proper exposure assessment by quantification of suitable biomarkers for different mycotoxins simultaneously. A rapid and direct LC-MS/MS method for the quantitative measurement of fifteen mycotoxins and key metabolites in human urine including deoxynivalenol (DON), DON-3-glucuronide, DON-15-glucuronide, DOM-1, nivalenol (NIV), T-2 and HT-2 toxin, zearalenone (ZEN), ZEN-14-glucuronide, α- and β-zearalenol, fumonisins B1 and B2, ochratoxin A and aflatoxin M1 was recently developed by our group. After validation, the method was applied in pilot surveys analyzing urine samples obtained from Cameroonian, Croatian and Austrian volunteers: In 63% of the Cameroonian samples (n=175) at least one analyte was detected and co-exposure to different mycotoxins was frequently observed. Overall, eleven analytes (DON, D3GlcA, D15GlcA, NIV, FB1, FB2, ZEN, α-ZEL, Z14GlcA, AFM1 and OTA) were determined in the samples in varying incidence and quantity. In one single sample up to six analytes (AFM1, DON, D15GlcA, NIV, FB1, and OTA) were found at the same time. In Croatian (n=40) and Austrian (n=27) samples DON metabolites were ubiquitous. The concentrations of urinary DON and its glucuronide conjugates were used to estimate the daily intake of this toxin. Notably, in Austria 33% and in Croatia 80% of individuals exceeded the provisional maximum tolerated daily intake (PMTDI) of 1 µg (kg bw)-1 d-1 assigned by the WHO. An urine excretion of 2 L per day, a urinary transfer rate of 72% and a constant urinary excretion of DON throughout a day was assumed for the estimation. The method was additionally applied to study human DON metabolism in vivo. DON and two closely eluting DON-glucuronides were determined and chromatographically separated in a naturally contaminated urine sample. In contrast to previous findings, we have tentatively identified D15GlcA as a major DON metabolite in human urine besides D3GlcA. These new findings clearly demonstrate the great potential of the developed multi-biomarker method to critically assess exposure of humans to “cocktails” of naturally occurring mycotoxins.

Biomarker; LC-MS/MS; mycotoxins; risk assessment

nije evidentirano