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The aim of this analysis was to assess the association between consumption of maize and dairy products and urine and serum levels of aflatoxin FM1 (AFM1) in a sample of 59 males occupationally exposed (29) and non-exposed (30) to aflatoxins. Two urine samples were collected for each person; each sample was accompanied by a questionnaire on food consumption in the preceding 96 h. Given the similar levels of contamination found in exposed and non-exposed workers, the association between food consumption and AFM1 levels was analyzed by pooling samples from exposed and non-exposed workers. No serum sample was found to be positive for AFM1, whereas 74% of the urine samples were positive; the average concentration of positive samples was 0.042 ng/mL (range < limit of detection (LoD) (0.002)-0.399 ng/mL). Of the 21 samples from maize consumers, 13 were positive for AFM1 (62%), with a mean concentration of 0.026 ng/mL (range 0.006-0.088 ng/mL), while 76% (74/94) of the samples from maize non-consumers were positive (mean 0.045, range < LoD (0.002)-0.399 ng/mL). No association was found with milk or dairy products. The high urine level of aflatoxins found in both exposed and non-exposed workers was not associated with the consumption of maize or cow milk products.

Mycotoxins are low molecular weight secondary metabolites produced by certain strains of filamentous fungi such as Aspergillus, Penicillium and Fusarium, which attack crops in the field, and grow on foods also during storage under favorable conditions of temperature and humidity. Foods mainly contributing to the intake of mycotoxins with diet are cereals, maize being the most risky commodity due to the potential co-occurrence of more than one mycotoxin, this can be of particular concern especially for vulnerable group of population such as celiac patients that show increased maize-based products consumption. In this study the exposure of celiac patients to fumonisins (FBs) and zearalenone (ZON) has been assessed. The higher exposures, for all the matrices and for both the selected mycotoxins, were for children age group. The lower and upper bound exposure ranged between 348-582 ng/kg bw/day for FBs and 22-83 ng/kg bw/day for ZON; these values result well below the TDI for the selected mycotoxins, representing the 17-29% and 9-33% of the TDI set for FBs and ZON, respectively. Even considering the worst scenario the exposure values reported for children were lower, namely 1385 ng/kg bw/day for FBs and 237 ng/kg bw/day for ZON, than the corresponding toxicological thresholds., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

Use of proper sampling methods throughout the agri-food chain is crucial when it comes to effectively detecting contaminants in foods and feeds. The objective of the study was to estimate the performance of sampling plan designs to determine aflatoxin B(1) (AFB(1)) contamination in corn fields. A total of 840 ears were selected from a corn field suspected of being contaminated with aflatoxin. The mean and variance among the aflatoxin values for each ear were 10.6 mug/kg and 2233.3, respectively. The variability and confidence intervals associated with sample means of a given size could be predicted using an equation associated with the normal distribution. Sample sizes of 248 and 674 ears would be required to estimate the true field concentration of 10.6 mug/kg within +/-50 and +/-30%, respectively. Using the distribution information from the study, operating characteristic curves were developed to show the performance of various sampling plan designs.

An interlaboratory study was conducted to evaluate the effectiveness of an immunoaffinity column cleanup liquid chromatography (LC) method for the determination of aflatoxin B1 levels in corn samples, enforced by European Union legislation. A test portion was extracted with methanol-water (80 + 20); the extract was filtered, diluted with phosphate-buffered saline solution, filtered on a microfiber glass filter, and applied to an immunoaffinity column. The column was washed with deionized water to remove interfering compounds, and the purified aflatoxin B1 was eluted with methanol. Aflatoxin B1 was separated and determined by reversed-phase LC with fluorescence detection after either pre- or postcolumn derivatization. Precolumn derivatization was achieved by generating the trifluoroacetic acid derivative, used by 8 laboratories. The postcolumn derivatization was achieved either with pyridinium hydrobromide perbromide, used by 16 laboratories, or with an electrochemical cell by the addition of bromide to the mobile phase, used by 5 laboratories. The derivatization techniques used were not significantly different when compared by the Student's t-test; the method was statistically evaluated for all the laboratories. Five corn sample materials, both spiked and naturally contaminated, were sent to 29 laboratories (22 Italian and 7 European). Test portions were spiked with aflatoxin B1 at levels of 2.00 and 5.00 ng/g. The mean values for recovery were 82% for the low level and 84% for the high contamination level. Based on results for spiked samples (blind pairs at 2 levels) as well as naturally contaminated samples (blind pairs at 3 levels), the values for relative standard deviation for repeatability (RSDr) ranged from 9.9 to 28.7%. The values for relative standard deviation for reproducibility (RSDR) ranged from 18.6 to 36.8%. The method demonstrated acceptable within- and between-laboratory precision for this matrix, as evidenced by the HorRat values.

The aim of this study was to investigate the distribution of aflatoxins and zearalenone levels in various corn-milling fractions. Corn kernels and six derived milling fractions (germ, bran, large and small grits, flour, and animal feed flour) were sampled in an industrial plant; both conventional and organic corns were sampled. To evaluate the effect of cooking, samples of polenta were prepared starting from naturally contaminated flour. Conventional and organic lots showed mycotoxin contamination. For both lots, germ, bran, and animal feed flour showed a marked concentration factor from 239 to 911% accounting for both the low yields of the derived products and the distribution of aflatoxins and zearalenone contamination in the outer parts of the kernels. Conversely, a reduction factor of at least four times from raw material to finished products was observed. Polenta samples were unaffected by the cooking process, with levels of contamination similar to those of starting flour.

The aim of this study was to investigate the distribution of fumonisin B1 in various corn milling fractions processed by an industrial plant. Corn kernels and six derived milling fractions (germ, bran, large and small grits, animal feed flour, and flour) were sampled. In addition, in order to evaluate the effect of cooking, samples of polenta were prepared starting from naturally contaminated flour obtained from the industrial processing cycle. The industrial plant worked continuously at a rate of 60 tons per day. Two sublots of 5 tons each were investigated with samples of derived products taken at regular time intervals. Due to a similar heterogeneous distribution of fumonisin B1 with other mycotoxins, such as aflatoxins, the sampling scheme was derived from the European Directive 98/53 for aflatoxins. Both lots of kernels showed fumonisin contamination at 4.54 and 5.09 mg/kg, respectively. Germ, bran, and animal feed flour showed contamination levels, namely 8.92 mg/kg (lot 1) and 9.56 mg/kg (lot 2), 7.08 mg/kg (lot 1) and 8.08 mg/kg (lot 2), and 9.36 mg/kg (lot 1) and 6.86 mg/kg (lot 2) higher than large and small grits and flour (0.39 mg/kg [lot 1] and 0.42 mg/kg [lot 2], 0.60 mg/kg [lot 1] and 1.01 mg/kg [lot 2], and 0.40 mg/kg [lot 1] and 0.45 mg/kg [lot 2], respectively). These results seem to account both for the industrial yields of the derived products and the distribution of fumonisin contamination in a kernel. The cooking of polenta in a domestic pressure cooker did not affect fumonisin contamination because the mycotoxin concentrations were similar to those of the starting flour (0.40 and 0.45 mg/kg).