We surveyed the presence of 22 mycotoxins in 191 Spanish cow milk samples. Mycotoxins could be carried over from diet into animal milk and have toxic effects on human and animal health. The interaction of different mycotoxins may be additive or synergetic. Therefore, surveillance of mycotoxin co-occurrence in milk is recommended. Aflatoxins M1, B1, B2, G1, and G2, ochratoxins A and B, nivalenol, deoxynivalenol, deepoxy-deoxynivalenol, 3- and 15-acetyldeoxynivalenol, diacetoxyscirpenol, neosolaniol, fusarenon X, T-2 and HT-2 toxins, fumonisins B1, B2, and B3, sterigmatocystin, and zearalenone were analyzed. Samples were treated by liquid-liquid extraction with acidified acetonitrile, followed by an acetonitrile-water phase separation using sodium acetate. The analysis was carried out by HPLC coupled to a triple quadrupole mass spectrometer. None of the analyzed mycotoxins had a concentration level higher than their detection limit (0.05–10.1 µg/L). The aflatoxin M1 in the samples never exceeded the level established by the European Union.
Mycotoxins, toxic secondary metabolites produced by different fungi, can occur naturally in raw products such as feedstuff. Although the rumen is supposed to be a barrier against mycotoxins, some studies demonstrate that carry-over of mycotoxins to milk is possible. Moreover, levels of different mycotoxin have been found in milk samples worldwide. Due to the low levels that are expected, methods with low detection limits are needed. Most of the reported analytical methods have been devoted to the analysis of one mycotoxin or family of mycotoxins, but the multi-exposure to mycotoxins is the most likely scenario. One fungal genus can produce more than one mycotoxin and the ruminant diet can be contaminated with more than one fungal genus. Therefore, analytical methods that can simultaneously detect and quantify a broad number of mycotoxins in milk that belong to different families and with low limits of detection and quantification are needed in order to reduce analytical costs and to facilitate the creation of better and fast monitoring programs in milk. On the other hand, milk is a high-consumption product and this makes it a product of high economic value. In 2015, milk production corresponded to the 14.1 % of the total agricultural production of the European Union. For these reasons, the objectives of this study were: to review the state of the art about the presence of mycotoxins in animal milk worldwide and the analytical methods for mycotoxin determination in milk, to develop and to validate LC-MS/MS methods for the simultaneous study of 22 mycotoxins in animal milk and to study the presence of 22 mycotoxins in Spanish and Peruvian cow milk. The mycotoxins studied were: nivalenol, deoxynivalenol, deepoxy-deoxynivalenol, 3-acetyldeoxynivalenol, 15-acetyldeoxynivalenol, neosolaniol, diacetoxyscirpenol, fusarenon X, T-2 and HT-2 toxins, aflatoxins M1, B1, B2, G1, G2, ochratoxins A and B, zearalenone, sterigmatocystin and fumonisins B1, B2 and B3. For validation, the parameters taken into account were: limits of detection and quantification, linearity, precision and accuracy (both in within-day and between-day conditions), recovery, matrix effect and stability. 191 Spanish cow milk were collected from different parts of Spain. No mycotoxin was detected. Also, 30 Peruvian cow milk were analyzed and ochratoxin A was found in levels below 0.2 ng/mL.
