Mycotoxins are toxic compounds for humans and animals that are produced by fungi. Mycotoxin contamination in feed is a global safety concern and effective control of these compounds in this matrix is needed. This study proposes a simple, cost-effective analytical method based on liquid chromatography coupled with a fluorescence detector, which is suitable for the routine monitoring of some of the most important mycotoxins in feed: aflatoxins (G2, G1, B2, and B1), zearalenone, and ochratoxins A and B. Mycotoxin extraction, chromatographic separation and quantification are carried out simultaneously for all mycotoxins. The extraction procedure is performed using acetonitrile, water and orthophosphoric acid (80:19:1). Purification of the extract is carried out using an OASIS PRIME HLB solid-phase extraction cartridge followed by a dispersive liquid–liquid microextraction procedure. Aflatoxins G1 and B1 are derivatized post-column (photochemical reactor at 254 nm) to increase their signal. The method has been validated in feed for pigs, cows, sheep, and poultry with very satisfactory results. The detection limits are 2 μg/kg for aflatoxins B1 and G1, 0.64 μg/kg for aflatoxins B2 and G2, 42 μg/kg for zearalenone, and 5 μg/kg for ochratoxins A and B. These values are low enough to allow for monitoring of these mycotoxins in feed. Global recovery values were between 73.6% and 88.0% for all toxins with a relative standard deviation (RSD) % < 7%. This methodology will facilitate laboratory control and analysis of mycotoxins in feed.

Mycotoxins, toxic compounds produced by fungi on raw materials, such as cereals, represent a serious health hazard. Animals are exposed to them mainly through the ingestion of contaminated feed. This study presents data about the presence and co-occurrence of nine mycotoxins: aflatoxins B1, B2, G1, and G2, ochratoxins A and B, zearalenone (ZEA), deoxynivalenol (DON), and sterigmatocystin (STER), in 400 samples of compound feed for cattle, pigs, poultry, and sheep (100 samples each) collected in Spain (2019–2020). Aflatoxins, ochratoxins, and ZEA were quantified using a previously validated HPLC method using fluorescence detection; whereas DON and STER were quantified using ELISA. Moreover, the obtained results were compared with those obtained in this country and published in the last 5 years. The mycotoxin presence in Spanish feed, especially for ZEA and DON, has been demonstrated. The maximum individual levels found were: AFB1: 6.9 µg/kg in a sample of feed for poultry; OTA: 65.5 µg/kg in a sample of feed for pigs, DON: 887 µg/kg in a sample of feed for sheep, and ZEA: 816 µg/kg in a sample of feed for pigs. Nevertheless, regulated mycotoxins appear, in general, at levels below those regulated by the EU; in fact, the percentage of samples containing concentrations above these limits was very low (from 0% for DON to 2.5% for ZEA). The co-occurrence of mycotoxins has also been demonstrated: 63.5% of the analyzed samples presented detectable levels of two to five mycotoxins. Due to the fact that the distribution of mycotoxins in raw materials can change greatly from year to year with climate conditions or market globalization, regular mycotoxin monitorization in feed is needed to prevent the integration of contaminated materials in the food chain.

Mycotoxins are of great concern in relation to food safety. When animals are exposed to them, health problems, economic losses in farms and related industries, and the carryover of these compounds to animal-derived foods can occur. Therefore, control of animal exposure is of great importance. This control may be carried out by analyzing raw material and/or feed or through the analysis of biomarkers of exposure in biological matrixes. This second approach has been chosen in the present study. Firstly, a methodology capable of analyzing mycotoxins and some derivatives (AFB1, OTA, ZEA, DON, 3- and 15-ADON, DOM-1, T-2, HT-2, AFM1, STER, NEO, DAS, FUS-X, AFB2, AFG1, AFG2, OTB, and NIV) by LC-MS/MS in human plasma, has been revalidated to be applied in animal plasma. Secondly, this methodology was used in 80 plasma samples obtained from animals dedicated to food production: cattle, pigs, poultry, and sheep (20 samples of each), with and without being treated with a mixture of β-glucuronidase-arylsulfatase to determine possible glucuronide and sulfate conjugates. Without enzymatic treatment, no mycotoxin was detected in any of the samples. Only one sample from poultry presented levels of DON and 3- and 15-ADON. With enzymatic treatment, only DON (1 sample) and STER were detected. The prevalence of STER was 100% of the samples, without significant differences among the four species; however, the prevalence and levels of this mycotoxin in the previously analyzed feed were low. This could be explained by the contamination of the farm environment. Animal biomonitoring can be a useful tool to assess animal exposure to mycotoxins. However, for these studies to be carried out and to be useful, knowledge must be increased on appropriate biomarkers for each mycotoxin in different animal species. In addition, adequate and validated analytical methods are needed, as well as knowledge of the relationships between the levels found in biological matrices and mycotoxin intake and toxicity.