|Name||Prof. John Berry|
|Organization or Institution||Florida International University|
Does Elevated Frequency and Measured Levels of Ochratoxin A (OTA) in U.S. Wines Suggest a Role of Climate Change?
Christopher L. De Jesus1 , Amanda Bartley1 , Aaron Z. Welch2 and John P. Berry1
1 Department of Chemistry and Biochemistry, Florida International University, 3000 NE 151 Street, North Miami, FL 33181
Ochratoxin A (OTA) is one of the most common fungal derived, i.e., mycotoxin, contaminants of agricultural products. Among the agricultural products found to be contaminated by OTA is wine (via contamination of grapes, and subsequently the "must" used in wine-making). Occurrence of OTA was evaluated in a representative sample of wines, specifically sourced from U.S. vineyards and wineries, by complementary analytical techniques including high-performance liquid chromatography (HPLC) coupled to fluorescence detection (FD) and mass spectrometry (MS), and commercially available enzyme-linked immunoassay (ELISA). Moreover, a simple and effective method based on HPLC-FD, following a simplified liquid-liquid extraction (LLE) technique, was developed and validated. In general, the occurrence of detectable/measurable (i.e., >LOD/LOQ) levels, as well as the measured levels, of OTA were high relative to previous assessments of the toxin among U.S. wines, and indeed, globally. Two wines were above current regulatory limits (i.e., 2 parts-per-billion [ppb]), and one was remarkably high at >8 ppb - and thus one of the highest levels measured, so far, for OTA in wine. Notably the levels and frequency were specifically high when compared to previous surveys of U.S. wines which were conducted well over a decade ago. Furthermore, both levels and frequency of OTA in wines showed a possible correlation with geography and climate of the wine source. Taken together, this study identified notably high incidence and levels of OTA in U.S. wines, and point to a possible effect of climate, and moreover, perhaps climate change, with respect to the occurrence of this toxin in agricultural products.