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Maize grain samples collected from 129 small-scale farmers' stores in southern and southwestern Ethiopia were analysed by LC-MS/MS for a total of 218 mycotoxins and other fungal metabolites of which 15% were regulated mycotoxins. Mycotoxins produced by Penicillium , Aspergillus , and Fusarium accounted for 31%, 17%, and 12% of the metabolites, respectively. Most of the current samples were contaminated by masked and/or emerging mycotoxins with moniliformin being the most prevalent one, contaminating 93% of the samples. Each sample was co-contaminated by 3 to 114 mycotoxins/fungal metabolites. Zearalenone, fumonisin B1, and deoxynivalenol were the dominant mycotoxins, occurring in 78%, 61%, and 55% of the samples with mean concentrations of 243, 429, and 530 µg/kg, respectively. The widespread co-occurrence of several mycotoxins in the samples may pose serious health risks due to synergistic/additional effects.

The occurrence of free and hidden fumonisins in raw maize and maize-based products from China was investigated. A total of 58 samples were analyzed using high-performance liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS). Among all the samples, 66% were contaminated with free fumonisins above limits of quantitation, and a higher percentage of 86% was found for total fumonisins (free + hidden). The highest contamination levels were observed in dried maize kernels which appeared mouldy, with mean levels of 15,737 and 30,785 µg/kg for free and total fumonisins, respectively. Frozen maize kernels, fresh maize kernels, and maize starch samples exhibited the lowest contamination levels, with no more than 200 µg/kg of total fumonisins. Except for one sample, the concentrations of total fumonisins were greater than those of free fumonisins with all the samples, the ratios of total-to-free fumonisins varied between 1.1 and 5.2, with an average ratio of 2.0.

In Argentina, wheat is the most consumed cereal by the human population. Since fumonisins occurence in wheat grains and wheat-based products have been reported worldwide, a survey was conducted in order to determine fumonisin contamination in 91 wheat-based products (white wheat flour samples, wheat flour used at bakery products and whole-wheat flour samples) collected from different retail stores of Rio Cuarto city in Argentina using HPLC-MS/MS. Sixty-seven samples (74%) showed contamination by fumonisins. From these samples, 16 showed fumonisin levels between LOD and LOQ (between 0.01 to 0.05 ng/g), while fumonisins (FB 1 + FB 2 ) in quantifiable samples ranged from 0.05 ng/g to 18.9 ng/g. Although FB 1 was more prevalent, FB 2 was foun3d in higher levels than FB 1 . Overall, fumonisin prevalence was high, but concentrations were far below EU or USA limits set for maize and maize-based products.

A total of 249 maize kernel samples from 8 maize-producing provinces of China were collected after the harvest season in 2014. All samples were analysed using high-performance liquid chromatography. The incidences of FBs (FB 1  + FB 2 ) from Guizhou, Hebei, Inner Mongolia, Shanxi, Chongqing, Liaoning, Heilongjiang, and Henan provinces were 71.4%, 73.8%, 28.0%, 52.6%, 85.0%, 87.5%, 38.1%, and 100.0%, respectively. The average concentration of FBs was 817 µg kg -1 and the concentrations ranged from <6 to 15,252 µg kg -1 . Among the 249 maize kernel samples, 28 samples exhibited higher levels as set by the Food and Drug Administration (2000 µg kg -1 ), whereas 12 samples exhibited higher levels as set by the European Commission (4000 µg kg -1 ). The average exposure to FBs (0.12 µg kg -1 body weight/day) is within the provisional maximum tolerable daily intake of 2.0 µg kg -1 body weight as set by the Joint FAO/WHO Expert Committee on Food Additives.

Natural contamination of sorghum grains by aflatoxin B 1 and total fumonisin and their producing toxigenic fungi has been studied. A total of 90 sorghum grain samples were collected from small-scale farmers' threshing floors and 5-6 months later from underground pits during 2013 harvest from three districts of East Hararghe, Ethiopia. Mycotoxin analysis was done using enzyme-linked immunosorbent assay (ELISA). The limits of detection were in the range 0.01-0.03 μg kg -1 . The results revealed that all sorghum grain samples were contaminated with both Aspergillus and Fusarium species. Aflatoxin B 1 was detected at levels ranging from -1 grain. There were marked variations in aflatoxin B 1 concentrations between fresh and stored samples, with much higher levels in the latter. Total fumonisin levels varied between 907 and 2041 µg kg -1 grain across the samples. Lowest total fumonisin was recorded in freshly harvested sorghum grain samples. Sorghum is a main staple cereal in the studied districts and its consumption per day per person is high. Daily intake of low doses of mycotoxin-contaminated food stuff over a period of time could lead to chronic mycotoxicosis.

A total of 225 maize kernel samples were collected from Shandong Province in China from 2012 to 2014 and analysed for contamination with Fusarium spp. and fumonisins (FBs) using molecular methods and high-performance liquid chromatography with fluorescence detection. The results showed that the average incidences of Fusarium spp. in 2012, 2013 and 2014 were 23.3%, 37.1% and 36.5%, respectively, Fusarium verticillioides being the predominant species. In 2012, the average contamination level of FBs was 3071 ng g(-1), which was higher than that in 2014 (2913 ng g(-1)) and 2013 (2072 ng g(-1)). Of all samples, 13% and 19% had FB contamination levels higher than 2000 and 4000 ng g(-1), which are the maximum limits as set by the Food and Drug Administration of the United States and the European Commission, respectively. Therefore, efforts should be taken to minimise the potential risk of FBs to the health of humans and animals.

Fumonisin occurrence was investigated in subsistence maize in four rural villages in each of Mbizana and Centane areas, South Africa. Samples (total 211) were analysed morphologically for Fusarium species and by high performance liquid chromatography for fumonisins. The mean incidence levels of Fusarium verticillioides in Centane good maize were 16% for both 1997 and 2000, but increased to 32% in 2003, whereas Mbizana good maize contained levels of 17% and 11% (2000 and 2003 seasons, respectively). The mean total fumonisin level in good maize in Centane for 1997 and 2000 was 575 and 975 µg/kg and 2150 µg/kg in 2003. In Mbizana, the mean total fumonisin level in good maize for 2000 was 950 µg/kg, but decreased to 610 µg/kg in 2003. The 2003 drought conditions led to a substantial increase in fumonisin levels in dry subhumid Centane, compared to humid subtropical Mbizana. This study emphasises the seasonal fluctuation in fumonisin levels.

This survey reports the occurrence of fumonisins (FBs) and fungi in dry soybeans sold for human consumption. The variation levels were 138-1495 µg kg(-1) and 178-552 µg kg(-1) for FB1 and FB2, respectively. In addition, potentially toxigenic fungi as Fusarium, Aspergillus and Penicillium genera were isolated in the samples. These can be considered as indicator-toxin and can produce considerable amounts of mycotoxins. Despite FB presence in the soybeans for human consumption, there is no legal regulation. Therefore, it is important to emphasise the need for frequent monitoring of these contaminants in soybeans.

In this study a total of 522 samples were collected from Shandong province of China in 2014 and analysed for the occurrence of fumonisin B1 (FB1), FB2 and FB3 by isotope dilution ultrahigh performance liquid chromatography-tandem mass spectrometry. Fumonisins were detected in 98.1% of the corn products, with the average total level of 369.2 μg kg(-1). The individual average values of FB1, FB2 and FB3 in corn products were 268.3, 53.7 and 47.2 μg kg(-1), respectively. The simultaneous occurrence of FB1, FB2 and FB3 was observed in 76.7% of the corn products. Especially, the results demonstrated that the difference in the contamination levels for fumonisins in these three types of corn products was apparent. In addition, 6.2% of the wheat flour samples were contaminated with FB1, with concentrations ranging from 0.3 to 34.6 µg kg(-1). No FB2 or FB3 was detected in wheat flour. In corn oil samples no fumonisins were detected.

A total of 125 maize kernel samples were collected from Hebei province in China during 2011-2013 and were analysed for incidence and contamination levels of fumonisins (FB₁ + FB₂) by HPLC with fluorescence detection. The incidence of FBs for all samples was 46.4%. The mean contamination level of FBs for the samples collected in 2013 was 706 μg kg⁻¹, which was higher than the levels in 2012 (429 μg kg⁻¹) and 2011 (250 μg kg⁻¹). All samples, except five, exhibited total FB levels below 4000 μg kg⁻¹, which is the maximum limit as set by the European Commission. The probable daily intakes of FBs (0.04 in 2011; 0.07 in 2012; 0.12 in 2013, expressed as μg kg⁻¹ body weight/day) were all within the provisional maximum tolerable daily intake of 2.0 μg kg⁻¹ of body weight/day as set by the Joint FAO/WHO Expert Committee on Food Additives. Nevertheless, monitoring is needed to prevent and control the potential risk of FB exposure to the consumers.

The aim of this study was to detect and quantify fumonisin B1 (FB1) in cereal mixtures marketed in Brazil. Fifteen samples from different lots were acquired each month by internet from supermarkets during seven months, adding up to 105 analysed samples. The unit sample constituted of an original package with a minimum of 250 g. Extraction and clean-up of samples for FB1 determination were carried out using immunoaffinity columns. Identification and quantification of FB1 were performed by high performance liquid chromatography. Eighty-eight (83.8%) samples were contaminated with FB1 and four (3.8%) presented levels above 500 µg kg(-1) (634, 703, 1269 and 1876 µg kg(-1)). Maximum FB1 + FB2 levels allowed by Brazilian regulations will reach 1500 µg kg(-1) for corn flour in 2016 and 1000 µg kg(-1) for others corn products. This study showed that even at levels below the legislative limits, human exposure to this toxin can occur constantly.

A total of 232 samples of corn commercialised in Santa Catarina state, Southern Brazil (temperate zone climate), were evaluated from 2007 to 2012 for fumonisins (FBs: FB1 and FB2). Before performing this study, a FBs method with liquid chromatography and fluorescence detection (ex. 335; em. 440 nm) was validated first. FBs were detected in 46.6% (108 samples), with values ranging from 66 to 7832 µg kg(-1) for FB1 and 110 to 1201 µg kg(-1) for FB2. The number of contaminated corn samples for FB1 and FB2 varied and often presented contamination of FB1 only. Per year of analysis, the numbers were: n = 22/8(FB1/FB2), 44/5(FB1/FB2), 25/12(FB1/FB2), 4(FB1), 6(FB1) and 7(FB1) in 2007, 2008, 2009, 2010, 2011 and 2012, respectively. The contamination percentage was 42.3/15.4, 59.5/6.8, 43.8/21.1, 36.4, 35.3 and 33.3%, respectively, during these years. Consumers can be exposed to these mycotoxins and their health can be at risk through the consumption of contaminated corn.

Monitoring results of food grain contamination with fusariotoxins-deoxynivalenol (DON), zearalenone (ZEN), fumonisins (FB1&FB2), T-2 and HT-2 toxins-are presented. Harvests of 2005-2010 in different regions of Russia were investigated. The occurrence of DON in wheat was 8%, barley 9%, oats 4%, rye 2% and maize 2%. The highest frequency of ZEN contamination was found in oats, the lowest in wheat. Calculated average daily intake of DON varied from 0.066 to 0.096 µg/kg body weight, the highest being found in the Southern region, but substantially lower than the provisional maximum tolerable daily intake. The results of enzyme-linked immunosorbent assay and high-performance liquid chromatography-mass spectrometry analysis demonstrated the presence of T-2 toxin in 14% and HT-2 toxin in 17% of all samples. The maximum level of T-2 toxin was exceeded only in one sample of barley. Relatively high frequency and levels of FB1&FB2 contamination were found in maize.

A total of 420 feedstuff samples were collected from China to determine and quantify T-2 toxin (T-2), zearalenone (ZEN) and fumonisin B₁ (FB₁). The contents of mycotoxins were determined by reverse-phase high-performance liquid chromatography with three-step cleanup and fluorescence detection. The mean recoveries of mycotoxins in spiked feedstuffs ranged from 72.2% to 95%. The limits of detection and quantification ranged from 1.8 to 5.7 and 6 to 19 µg/kg, respectively. Of the 420 analysed feedstuff samples, the incidence of T-2, ZEN and FB₁ was 79.5%, 85.2% and 96.1%, respectively; levels detected ranged from 10-735, 35-1478 and 20-6568 µg/kg, respectively. The results suggest a risk for domestic animals and humans. Further, the procedure was found to be suitable for determination of mycotoxins in feedstuffs and can be used for routine analysis. This is the first report in China on natural contamination of feedstuffs with these mycotoxins.

A total of 120 pelleted poultry feed samples from Entre Ríos Province, Argentina, were evaluated. The aims were to investigate (1) the presence of relevant toxigenic fungi, as well as to determine the ability to produce aflatoxins (AFs) by Aspergillus section Flavi isolated strains; and (2) the natural co-occurrence of AFs, fumonisins (FBs), gliotoxin, diacetoxyscirpenol (DAS), HT-2 and T-2 toxin by high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). Total fungal counts were below the established value (1 × 10⁴ CFU g⁻¹). Aspergillus flavus and A. parasiticus were the only aflatoxigenic species isolated. Co-occurrence of fumonisin B₁ (FB₁), HT-2 and T-2 toxin was detected in 100% of the feeds, with mean levels from 4502 to 5813; 6.7 to 21.6 and 19.6 to 30.3 µg kg⁻¹, respectively. A large number of starter samples were co-contaminated with aflatoxin B₁ (AFB₁), FB₁, HT-2 and T-2 toxins. Gliotoxin and DAS were not found in this survey.

Fumonisins B₁, B₂ and B₃ (FB₁, FB₂ and FB₃) and aflatoxins B₁ (AFB₁), B₂ (AFB₂), G₁ (AFG₁) and G₂ (AFG₂) are both major mycotoxins of food concern, because of their wide range of concentration and possible co-occurrence. Therefore, a contamination survey in corn and wheat flour by liquid chromatography-tandem mass spectrometry was carried out. Quantification of fumonisins and aflatoxins was based on internal calibration (by the use of ¹³C₃₄-fumonisin) and external calibration, respectively. Fumonisins were detected in 95% of corn samples and in 7% of wheat flour samples, with the mean level (FB₁ + FB₂ + FB₃) of 441 µg kg⁻¹ and 0.09 µg kg⁻¹, respectively. Low levels of aflatoxins were detected in 37% of the samples with a mean level (B₁ + B₂ + G₁ + G₂) of 0.12 µg kg⁻¹. Fumonisins and aflatoxins were not detected in 29% of the samples analysed. Simultaneous occurrence of fumonisins and aflatoxins was observed in 12% of samples.

Maize (Zea mays) is one of the most common crops in Croatia that is often contaminated with mycotoxins. The enzyme linked immunosorbent assay (ELISA) method as a screening immunological method has become very popular in the determination of mycotoxins contamination of cereals, as it has many advantages such as a rapid and simple determination of their concentration. In this present study, 40 maize samples collected from animal feed factories were analyzed for the concentration of deoxynivalenol (DON) and fumonisin (FUM) using the validated ELISA method of two different kit manufacturers to investigate the correlation of the determined mycotoxins concentration. The correlation coefficients for the concentration of DON and FUM, obtained using different kit manufacturers, were r = 0.9698 and r = 0.9303, respectively, yielding a high correlation between the applied ELISA methods. Concerning the legislation, in one maize sample, the DON concentration higher than the maximum recommended value was determined (16.24 mg/kg), whereas the FUM concentration in all the analyzed samples, without exception, were in accordance with recommended values.

The mycoflora and mycotoxins contamination of commercial maize and rice grains collected from local markets of the major five zones of the province of Cairo, Egypt, represented by 20 different districts were studied. A total number of about 23 species belonging to 12 different genera of fungi were isolated and identified. About 70% of the samples were infected with Aspergillus flavus and Aspergillus niger, with percentages of 33%, 40% recovered from maize and 46%, 27% recovered from rice, respectively. The percentages of infection of maize ranged from 16% to 142%. The percentages of infection of rice seeds ranged from 6% to 93%. Total aflatoxins and fumonisins detected in maize averaged 9.75 and 33 µg/kg, respectively. Total aflatoxins and fumonisins detected in rice averaged 5.15 and 1014 µg/kg, respectively.

Between February and October 2009, 324 grain, feed and feed commodity samples were sourced directly at animal farms or feed production sites in Middle East and Africa and tested for the presence of A- and B-trichothecenes, zearalenone, fumonisins, aflatoxins and ochratoxin A, or for selected groups of mycotoxins only. Samples were analyzed after clean-up by immunoaffinity or solid-phase extraction followed by HPLC with derivatization where appropriate and fluorescence, UV or mass spectrometric detection. The percentage of positive samples of B-trichothecenes ranged from 0 to 87% of tested samples. The prevalence of fumonisins in the different countries was >50% in most cases. Zearalenone was present in tested commodities from all countries except three. The presence of aflatoxin in analyzed samples varied from 0 to 94%. Ochratoxin A was present in 67% of samples in Sudan and in 100% of Nigerian samples. No A-trichothecenes were found in this survey.

We analysed a total of 2258 grain samples over a 3-year period (2006-2008) from 93 storage centers in the principal maize cultivation area of Italy to establish the levels of fumonisin contamination. Fumonisin concentrations were measured using ELISA (RIDASCREEN) fumonisin test kits. Mean levels of contamination were remarkably high in each year, with the highest value in 2006 (10.9 mg/kg) and the lowest in 2008 (4.8 mg/kg). Similarly, for each year, variations were quite large: from

A survey was conducted to determine the occurrence of fumonisin B1, B2 and B3 during 2007 in 186 samples of organic and conventional locally available corn products. Samples included baby food (n = 62), corn flour (11), cornflakes (23), pasta (14), cookies (17) and other corn products (59) were obtained from popular markets of Valencia (Spain) and Perugia (Italy). The analytical method used pressurized liquid extraction and liquid chromatography/electrospray ionization tandem mass spectrometry with a triple quadrupole (QqQ) analyser. Of the 104 Spanish samples, 22% contained levels in the range of 2-449 µg kg(-1), 2-229 µg kg(-1) and 6-105 µg kg(-1) for FB1, FB2 and FB3, respectively, while 19 (23%) of the 82 Italian samples were positive with quantifiable levels between 2-235 µg kg(-1), 3-187 µg kg(-1), and 4-40 µg kg(-1) for fumonisins B1, B2 and B3, respectively. Overall, none of the Italian samples and only one organic baby food sample from a Spanish market was above the maximum permitted levels established by European legislation. Fumonisins were found mostly in corn flour followed by cookies and cornflakes. Eleven samples from Spain and nine samples from Italy were organic products, being contaminated the 72% and 77% of the samples, respectively. Analysis of the results showed that levels of fumonisins in corn products were similar in Italy and Spain. The safety of fumonisin intake through corn products was demonstrated by the calculation of the estimated daily intake of both populations considering organic and conventional products separately, which ranged from 1.7 × 10(-3) to 0.72 µg kg(-1) bw day(-1) and comparing them with the provisional maximum total daily intake (PMTDI) of 2 µg kg(-1) bw day(-1) established by the European Union.

The investigation of adverse health effects associated with fungal mycotoxins requires the measurement of human exposure. Most frequently, this exposure is estimated from contamination levels of raw foodstuffs, which are the primary source of toxin exposure, and data on food consumption patterns. However, variations in food preparation methods, food intake, contamination level, intestinal absorption, toxin distribution and excretion lead to individual variations in toxin exposure that are more readily measured with a biomarker. Fumonisin biomarkers have been sought in the measurement of levels of the toxin in physiological samples such as serum, urine, faeces, hair and nails. However, due to the low bioavailability of fumonisin, these samples pose a variety of analytical challenges and also still require validation as biomarkers. The most widely researched fumonisin biomarkers have been those related to the disruption of de novo sphingolipid biosynthesis, namely elevated levels of the sphingoid base, sphinganine, or of its ratio with sphingosine. Elevation of these parameters in humans would potentially provide a biomarker of biochemical effect. A number of investigations into the possible elevation of sphinganine (or its ratio with sphingosine) in human blood and urine have generally failed to correlate with estimates of fumonisin exposure. The sphingoid bases occur naturally in human blood and urine such that their levels have normal ranges, which can be influenced by dietary factors other than fumonisin ingestion. The lower exposures from human diets, as compared with doses in experimental animals, have made detection of changes in these sphingoid biomarkers problematic.

A survey for the natural occurrence of Fusarium mycotoxins in maize for human consumption in four south-western states of Nigeria using High Performance Liquid Chromatography coupled with Mass Spectroscopy (HPLC/MS) showed that 93.4% of the samples were contaminated with zearalenone (ZON), alpha- and beta-zearalenols (alpha- and beta-ZOL), fumonisin B(1) (FB(1)) or enniatins (ENNs). The fractions of contaminated samples were 73% for FB(1) (mean:117 microg kg(-1), range:10-760 microg kg(-1)); 57% for ZON (mean:49 microg kg(-1), range:115-779 microg kg(-1)) and 13% for alpha-ZOL (mean: 63.6 microg kg(-1), range:32-181 microg kg(-1)), while ENNs A1, B and B(1) were present in 3, 7 and 3% of the samples respectively. There was no beta-ZOL present above the quantification limits of 50 microg kg(-1). Only the FB(1) content was significantly different at the 95% confidence level among the four states. The Fusarium species most frequently isolated from maize seeds were F. verticillioides (70%), followed by F. sporotrichioides (42%), F. graminearum (30%), F. pallidoroseum (15%), F. compactum (12%), F. proliferatum (12%), F. equiseti (9%), F. acuminatum (8%) and F. subglutinans (4%). This is the first report of the occurrence of alpha-zearalenol and enniatins in Nigerian maize.

Fumonisins are metabolites produced in corn primarily by the fungus Fusarium verticillioides (F. moniliforme) and are toxic to humans and animals. Fumonisin B(1) (FB(1)) is the primary fumonisin produced and is found frequently in corn kernels, some of which may be used as food or food ingredients. A three-part study was conducted to determine the effects of gamma- and electron beam irradiation on the levels of fumonisins in naturally contaminated field corn, and the effects of microwave-popping on fumonisins in selected, naturally contaminated popcorn. To date, no effective means have been found to reduce consistently mycotoxin levels once foods are contaminated. Aqueous solutions of FB(1) at various concentrations, samples of whole corn, and samples of ground corn containing known levels of FB(1) were irradiated with various levels of cobalt and electron beam irradiation. Popcorn samples, taken from the reject streams of popcorn processing, were popped using normal microwave-popping conditions. FB(1) in aqueous solutions was reduced by 99.7% using a minimal level of irradiation (0.5 kGray). Gamma- and electron beam irradiation did not significantly reduce levels of FB(1) in whole and ground corn. Aspergillus sp., Penicillium sp. and Fusarium sp. fungi were totally eliminated at 30 kGray in ground corn and at 100 kGray in whole corn. The normal commercial cleaning processes for microwave popcorn before packaging reduced fumonisins to <0.03 microg g(-1) for the cleaned product stream. Microwave popping of popcorn from reject streams of the cleaning operation that contained fumonisins resulted in significant reduction of the mould toxin.

The fumonisins are mycotoxins produced mainly by Fusarium verticillioides and F. proliferatum in maize, the predominant cereal staple for subsistence farming communities in southern Africa. In order to assess exposure to these mycotoxins in the Bizana (now known as Mbizana) and Centane magisterial areas of the former Transkei region of the Eastern Cape Province of South Africa, the actual maize consumption by different age groups in these communities was measured. In the groups 1-9 years (n = 215) and 10-17 (n = 240) years, mean consumption (+/-standard error) was 246 +/- 10.8 and 368 +/- 10.3 g per person day(-1), respectively, with no significant difference (p > 0.05) between the magisterial areas. For adults (18-65 years) mean maize consumption in Bizana (n = 229) and Centane (n = 178) were significantly different (p < 0.05) at 379 +/- 10.5 and 456 +/- 11.9 g per person day(-1), respectively. An exposure assessment was performed by combining the maize consumption distribution with previously determined levels of total fumonisin (fumonisins B(1) and B(2) combined) contamination in home-grown maize in these two areas. Assuming an individual adult body weight of 60 kg, fumonisin exposure in Bizana, an area of relatively low oesophageal cancer incidence, was 3.43 +/- 0.15 microg kg(-1) body weight day(-1), which was significantly lower (p < 0.05) than that in Centane (8.67 +/- 0.18 microg kg(-1) body weight day(-1)), an area of high oesophageal cancer incidence. Mean fumonisin exposures in all age groups in both Bizana and Centane were above the provisional maximum tolerable daily intake (PMTDI) of 2 microg kg(-1) body weight day(-1) set by the Joint FAO/WHO Expert Committee on Food Additives.

Fumonisin B(1) (FB(1)) and fumonisin B(2) (FB(2)) are mycotoxins mainly produced by Fusarium verticillioides and Fusarium proliferatum, which are field pathogens of maize. A survey was conducted on the incidences of FB(1) and FB(2) in both maize and derived products purchased in Portugal. The analytical method involved extraction with methanol-water, clean-up by immunoaffinity column and derivatization with naphthalene-2,3-dicarboxaldehyde. Determination was carried out by high-performance liquid chromatography (HPLC) with spectrofluorimetric detection, with liquid chromatography/mass spectrometry (LC/MS) confirmation. The presence of FB(1) and FB(2) was determined in 67 samples of maize and maize-based foods, such as flour, semolina, starch, sweet maize, cornflakes and other breakfast cereals, and snacks collected in 2005. FBs were found in 15 samples at concentrations ranging from 113 to 2026 microg kg(-1). Two of the samples showed higher contamination levels than the limits established by the European Commission Regulation. None of the samples contained levels of fumonisins that would lead to an exposure exceeding the tolerable daily intake (TDI).

Fumonisin B1 (FB1) is reportedly the causative agent of several animal mycotoxicoses and has etiologically been linked to human oesophageal and liver cancer in certain areas of South Africa and China. To study a possible relationship between exposure to FB1 and human cancer risk, the current status of FB1 contamination in food samples in Huaian and Fusui, where incidences of oesophageal and liver cancer are amongst the highest in China, was investigated. A total of 259 corn samples were collected from individual households in five villages of different townships in Huaian during December 2001 and December 2002, and in four villages of different townships in Fusui during May 2001 and May 2002. Corn samples were also collected from individual households in two villages in Huantai, an area with low incidences of both cancers. Enzyme-linked immunosorbent assays (ELISA) and immunoaffinity-HPLC methods were used for FB1 analysis. In corn samples from Huaian, FB1 was detectable in 95.7% (112/117) of the samples, with an average of 2.84 mg kg-1 (range 0.1-25.5 mg kg-1). FB1 was detected in 83.0% (78/94) of the Fusui samples, with an average of 1.27 mg kg-1 (range 0.1-14.9 mg kg-1), and in 83.3% (40/48) of Huantai samples, with an average of 0.65 mg kg-1 ranging from 0.1 to 5.7 mg kg-1. The level of FB1 in corn samples from Huaian was significantly higher than from Huantai (P < 0.001). In addition, 47 of 112 (42.0%) positive Huaian samples had FB1 level greater than 2.0 mg kg-1, which was significantly higher than 10.0% (4/40) of Huantai samples (P < 0.001). Furthermore, variations were found between samples collected in different years and different villages. The high contamination rates of FB1 found in food from these areas, along with previous reports, suggest a possible contributing role of FB1 in human esophageal- and hepato-carcinogenesis.

This survey examined 30 samples of rice (n = 10), maize (n = 10) and peanuts (n = 10) from Côte d'Ivoire for aflatoxin B1, fumonisin B1 and zearalenone using immunoassays, and ochratoxin A using a validated HPLC method with fluorescence detection. In Côte d'Ivoire, as in other countries, several mycotoxins are present in the same commodities. These mycotoxins are from different structural families: aflatoxin B1, fumonisin B1, zearalenone and ochratoxin A, normally produced by fungal species from Aspergillus, Penicillium and Fusarium genera. Some samples contained four mycotoxins (86%). Four peanuts samples did not show ochratoxin A (14%), whereas they contained aflatoxin B1 concentrations above the EU regulatory limits. Concentrations of ochratoxin A, zearalenone and fumonisin B1 were low and may not cause problems per se; however, fears remain that the tolerable daily intake may be exceeded due to eating habits and synergistic effects could be important with the combination of several mycotoxins. Investigations in this direction are underway, together with isolation and characterization of the fungal species involved.

Fumonisins are mycotoxins found in maize. In developing countries, the resources required for analysis are often lacking, and the shipping of maize between countries can be difficult since the importation of plant materials requires permits/inspection to prevent the entry of pests that frequently infest maize. A simple, safe and legal method for shipping maize extracts to the USA was needed to conduct a survey of fumonisins in Central America. The objective was to develop a method for isolating and shipping maize extracts for fumonisin analysis so as to facilitate a survey of fumonisin exposure. The results indicate that fumonisins in acetonitrile:water extracts of maize can be isolated on C18 cartridges, held for at least 3 days at 22 degrees C and then an additional 4 days at 4 degrees C before elution and analysis with no losses. This method allows the importation and analysis of maize samples from foreign locations without complications from international safety concerns.

Nixtamalization removes fumonisins from corn and reduces their amounts in masa and tortilla products. Fumonisin concentrations and potential toxicity could be underestimated, however, if unknown but biologically active fumonisins are present. Therefore, the relative amounts of fumonisins in extracts of fumonisin-contaminated corn and its masa and tortilla chip nixtamalization products were determined with an in vitro ceramide synthase inhibition bioassay using increased sphinganine (Sa) and sphinganine to sphingosine ratio (Sa/So) as endpoints. African green monkey kidney cells (Vero cells ATCC CCL-81) were grown in 1-ml wells and exposed to 4 microl of the concentrated extracts for 48 h. The corn extract inhibited ceramide synthase as Sa (mean = 132 pmol/well) and Sa/So (mean = 2.24) were high compared to vehicle controls (Sa = 9 pmol/well; Sa/So = 0.10). Inhibitory activity (mean Sa = 14-24 pmol/well; mean Sa/So = 0.17-0.28) of the masa and tortilla chip extracts were reduced > or = 80% compared to the corn extract. Results were corroborated in a second experiment in which Sa and Sa/So of the wells treated with masa or tortilla chip extracts were reduced > or = 89% compared to those treated with the corn extract. Masa and tortilla chip FB1 concentrations (4-7 ppm) were reduced about 80-90% compared to the corn (30 ppm) when the materials were analyzed by high-performance liquid chromatography (HPLC). Therefore, nixtamalization reduced both the measured amount of FB1 and the ceramide synthase inhibitory activity of masa and tortilla chips extracts. The results further suggest that the masa and tortilla chip extracts did not contain significant amounts of unknown fumonisins having ceramide synthase inhibitory activity.

The distribution and elimination of fumonisins after oral administration of 50 mg FB(1), 20 mg FB(2) and 5 mg FB(3) per animal day(-1) for 22 days was studied in weaned barrows. At the end of the trial, the lung, heart, liver, kidney, spleen, brain, serum, bile, muscle, fat, urine and faeces samples were collected and their content of fumonisins (FB(1), FB(2)) determined by LC-MS. The highest FB(1) concentrations were found in the liver (99.4 +/- 37.5 ng g(-1)) and kidneys (30.6 +/- 10.1 ng g(-1)), whilst the highest average amount of FB(2) was in the liver (1.4 +/- 2.3 ng g(-1)) and fat (2.6 ng g(-1) +/- 4.8) samples. Comparing the FB(1)/FB(2) ratio in different organs (19/1), it was found that the ratio in the abdominal and subcutaneous fat samples (4/1) was markedly different from those in all other tissues, namely the relative proportion of FB(2) was higher in latter cases. Of the total quantity of FB(1), the 13% taken up during 5 days was excreted unchanged with the faeces and urine. On average, in the urine and faeces, FB(1) was detected in nine- and 14-fold quantities, as compared with FB(2).

Mechanical shelling and dehulling methods were tested to evaluate their impact on Fusarium infection and fumonisin contamination in maize. All shelling methods which were tested were found to damage the grains. The IITA sheller caused the highest level (up to 3.5%) of damage. Fusarium populations were higher on damaged grains, the highest being recorded from grains damaged by the IITA sheller (2,533.3 cfu g(-1)). Fumonisin levels were higher in damaged grains, the highest being in maize shelled with the IITA sheller (2.2 mg kg(-1)). Fumonisin levels were positively and significantly correlated with the percentage of damage caused by the shelling methods, and with the number of Fusarium colonies in maize. Mechanical dehulling methods significantly reduced fumonisin levels in maize, resulting in a mean reduction of 62% for Mini-PRL, 65% for Engelberg, and 57% for the attrition disc mill. It is important for farmers to choose appropriate shelling methods to reduce mycotoxin contamination. Dehulling should be widely promoted for the reduction of mycotoxins in maize.

This study reports estimates on dietary exposure from the first French Total Diet Study (FTDS) and compares these estimates with both existing tolerable daily intakes for these toxins and the intakes calculated during previous French studies. To estimate the dietary exposure of the French population to the principal mycotoxins in the French diet (as consumed), 456 composite samples were prepared from 2280 individual samples and analysed for aflatoxins, ochratoxin A, trichothecenes, zearalenone, fumonisins and patulin. Average and high percentile intakes were calculated taking account of different eating patterns for adults, children and vegetarians. The results showed that contaminant levels observed in the foods examined 'as consumed' complied fully with current European legislation. However, particular attention needs to be paid to the exposure of specific population groups, such as children and vegans/macrobiotics, who could be exposed to certain mycotoxins in quantities that exceed the tolerable or weekly daily intake levels. This observation is particularly relevant with respect to ochratoxin A, deoxynivalenol and zearalenone. For these mycotoxins, cereals and cereal products were the main contributors to high exposure.

Thirty samples of asparagus spears were collected from the fields in Shandong province, China, in July 2004, and were analysed for the occurrence of fumonisins B1 and B2 (FB1 and FB2) by HPLC coupled with electrospray ionization tandem mass spectrometry. Twenty-four samples (80%) contained fumonisins, ranging from 24 to 670 ng g(-1) (average 123 ng g(-1)) and 17 to 138 ng g(-1)(average 35 ng g(-1)) for FB1 and FB2, respectively. The total amount of fumonisins (FB1 and FB2) in all samples ranged from 47 to 714 ng g(-1) (average 158 ng g(-1)) (based on dry weight). This is the first report on the natural occurrence of FB1 and FB2 in asparagus spears in China.

Mycotoxins are products of moulds that frequently contaminate maize. In this study the presence of mycotoxins fumonisin B1 (FB1), fumonisin B2 (FB2), zearalenone (ZEA) and ochratoxin A (OTA) was determined in 49 maize grain samples collected in autumn 2002. The most frequent finding was that of FB1(100%), followed by ZEA (84%) and OTA (39%), while FB2 was found only in three samples. The co-occurrence of two and three mycotoxins was found in 55 and 37% of samples, respectively. The concentrations (mean +/- SD) of FB1, ZEA and OTA in positive samples were 459.8 +/- 310.7, 3.84 +/- 6.68 and 1.47 +/- 0.38 microg kg(-1), respectively, and the concentrations of FB2 in three positive samples were 68.4, 109.2 and 3084.0 microg kg(-1). Although such low concentrations of mycotoxins are not a significant source of exposure in countries with a European diet, a few samples with extreme values indicate that thorough control is needed.

Extrusion cooking is one of the fastest growing food-processing operations in recent years due to several advantages over traditional methods. Apart from its main goal of improving the quality of intermediate and final processed products, it may incidentally also improve safety because of the potential to reduce mycotoxin levels in cereals. This review is focused on extrusion cooking and aims to give a general overview of its impact in reducing mycotoxin levels in cereals. Extrusion cooking generally decreases the mycotoxins levels at rates depending on different factors such as the type of extruder, the type of screw, the die configuration, the initial mycotoxin concentration, the barrel temperature, the screw speed, the moisture content of the raw material and the use of additives. Reductions of 100, 95 and 83% for fumonisins, aflatoxins and zearalenone, respectively, have been reported during extrusion cooking of cereals, while lower reductions were observed for deoxynivalenol, ochratoxin A and moniliformin, where maximum reductions did not exceed 55, 40 and 30%, respectively.

Thirty retail samples of heat-processed corn foods, i.e. corn flakes, corn-based breakfast cereals, tortilla chips and corn chips, were analysed for fumonisins--fumonisin B1 (FB1), fumonisin B2 (FB2) and hydrolysed FB1 (HFB1)--as well as for protein- and total-bound FB1. Bound (hidden) fumonisins cannot be detected by conventional analysis. Improved methods for the determination of bound FB1 were developed. The protein-bound FB1 was extracted with 1% sodium dodecylsulfate (SDS) solution. The SDS, which interfered with high-performance liquid chromatography (HPLC) analysis, was then separated from protein-bound FB1 by complexing with methylene blue followed by solvent extraction and hydrolysis with 2 N KOH. To measure total-bound FB1, the sample itself was hydrolysed with KOH. In both cases, clean-up was accomplished on an OASIS polymeric solid-phase extraction column and the bound fumonisins were determined by HPLC measurement of HFB1. Fourteen of 15 samples of corn flakes and other corn-based breakfast cereals analysed contained detectable levels of FB1 with a mean in positive samples of 67ng g(-1) (13-237 ng g(-1)). Two samples also had detectable levels of FB2 (21-23ng g(-1)). Bound FB1 was found in all samples; the mean protein-bound FB1 measured was 58 ng g(-1) (22-176 ng g(-1)) and the mean total-bound FB1 measured was 106 ng g(-1) (28-418 ng g(-1)), reported as FB1 equivalents after correction for recoveries of HFB1. There was an average of about 1.3 times more FB1 in the bound form compared with extractable FB1, and this was about twice as much as protein-bound FB1. Seven of the 15 samples of alkali-processed corn-based foods, such as tortilla chips and corn chips, contained FB1 and three contained HFB1 with means in measurable positive samples of 78 (48-134) and 29 (13-47) ng g(-1), respectively. Five of these alkali-processed corn foods contained bound FB1; the mean measurable protein-bound FB1 was 42 ng g(-1) (39-46 ng g(-1)) and the mean measurable total-bound FB1 was 100 ng g(-1) (54-209 ng g(-1)). HFB1 derived from bound FB1 in selected samples was confirmed by HPLC with mass spectrometry (MS).

The increased sphinganine/sphingosine (SA/SO) ratio has previously been shown as a biomarker of fumonisin exposure in experimental animals and has been proposed as a tool to assess human exposure to fumonisin mainly occurring through the dietary consumption of fumonisin contaminated maize-based foods. Sphinganine and sphingosine were measured in urines of humans resident in two areas of North Argentina and South Brazil with high maize consumption and compared with urine samples collected in areas with very low or no maize consumption, such as Central Argentina and Southern Italy. The pattern of SA/SO values in the two groups with no maize consumption (assumed as controls) was similar, with all SA/SO values lower than one. Mean SA/SO ratio was 1.27 in urine of subjects with high maize consumption (n = 123) and 0.36 in controls (n = 66) and the difference was statistically significant (p<0.001). The mean fumonisin level in maize samples collected in North Argentina and South Brazil was 0.35 mg kg(-1) (n = 40). Although a similar maize and fumonisin intake was recorded for the two groups of populations, the mean SA/SO ratio in South Brazil (1.57) was significantly higher (p<0.05) than that of North Argentina (0.69). These data suggest that the higher SA/SO values observed in South Brazil cannot be associated with high fumonisin exposure and further studies are necessary to provide convincing evidence for using the SA/SO ratio as a biomarker of human fumonisin exposure.

Maize throughout the world is frequently contaminated with a family of mycotoxins, the fumonisins, produced by species of Fusaria. The study investigated the level of fumonisin contamination of maize samples from village farms and large market traders in Burkina Faso, West Africa. Maize samples (5 kg) from each of five to six large storage barns from farms in five villages in the district of N'Dorola, Kénédougou province, western Burkina Faso, were sampled (n = 26) in Jan 1999 (> 1 year storage), and a further 26 maize samples from the same farms were collected directly from the field in October 1999. In addition, 72 maize samples were obtained in July 1999 from large markets in Bobo Dioulasso. Fumonisins were extracted from dried maize, derivatized with o-phthaldialdehyde and quantified by reversed-phase high-performance liquid chromatography with fluorescence detection. All 26 samples from the first (mean 1170 microg kg(-1), range 110-3120 microg kg(-1)) and from the second (mean 130 microg kg(-1), range 10-450 microg kg(-1)) village collection were fumonisin positive. All 72 maize samples from the large markets were also positive for fumonisins, and had the highest levels of contamination (mean 2900 microg kg(-1), range 130-16,040 microg kg(-1)). As fumonisins were a ubiquitous contaminant of maize and given that this crop is a dietary staple in this region, chronic exposure is likely.

A survey of 196 samples of corn-based infant foods from 13 cities of Sao Paulo State, Brazil, was carried out to investigate the fumonisin contamination in the products. Based on their ingredients, the products were divided into seven groups: infant cereal designated as types A-D, corn meal, corn starch and instant cereal baby food. Although certain infant food samples were free of fumonisin contamination (<20 microg kg(-1); corn starch and infant cereals of type A, B and D), contamination levels in the other products (corn meal, instant corn-based baby food and cereal type C) were of concern, particularly those in corn meal. All samples in these categories contained fumonisins. The mean level for total fumonisins (FB1 + FB2 + FB3) in corn meal was 2242 microg kg(-1) (maximum 8039 microg kg(-1)), in instant corn-based baby food was 437 (maximum 1096) microg kg(-1) and in infant cereal type C was 664 (maximum 1753) microg kg(-1).

A method for the simultaneous quantitative determination of deoxynivalenol (DON), fumonisin B1 (FB1) and zearalenone (ZEN) in maize by liquid chromatography-atmospheric pressure chemical ionization tandem mass spectrometry (LC-APCIMS/MS), using stable isotopically labelled and structural analogues internal standards, is described. The procedure involves accelerated solvent extraction followed by two solid-phase clean-up steps on strong anion exchange resin and a Mycosep column. Typical recoveries were calculated by spiking blank maize at three different concentrations for deoxynivalenol (200, 400 and 1000 microg kg(-1)) at 70%, for fumonisin B1 (100, 200 and 1000 microg kg(-1)) at 90%, and for zearalenone (50, 100 and 200 microg kg(-1)) at 40%. LC-APCIMS/MS analyses were realized in collision-induced dissociation on an ion-trap instrument to provide a high degree of selectivity and sensitivity. Extraction of ions from two transition reactions, monitored by LC-APCIMS/MS for each analyte, enabled a limit of detection for DON, FB1 and ZEN at, respectively, 10, 20 and 3 microg kg(-1), and a limit of quantification at, respectively, 50, 50 and 10 microg kg(-1). The robustness of the method was also evaluated with the analysis of wheat samples.

A simple and cost-effective method using thin-layer chromatography for the determination of the mycotoxin fumonisin B1 in maize is described. The analytical method consisted of the extraction of ground maize by shaking with methanol/water (75:25) for 60 min and clean-up of the resultant extract by means of strong anion exchange solid-phase extraction. The purified residue, formed by evaporation of the elution solvent, was reacted with fluorescamine and the fumonisin B1-derivative was separated by reversed-phase thin-layer chromatography using a developing solution of methanol/aqueous 4% potassium chloride (70:30). The derivatized FB1 was readily visualized as a greenish-yellow spot under long wavelength ultraviolet light and quantified by visual comparison with a set of similarly derivatized standards in the range 20-300 ng FB1 spotted on plate. Based on visual comparison, levels down to 0.5 mg kg(-1) were successfully estimated. The method was collaboratively studied in 14 laboratories using four duplicate maize meal samples (including a blank) and a spiked sample for determination of recovery. No significant difference was observed between mean FB1 levels by high-performance liquid chromatography or thin-layer chromatography. Based on within-laboratory relative standard deviations of 27.1-41.7% and between-laboratory relative standard deviations of 35.0-63.3%, the method can be considered semiquantitative. The mean recovery achieved by participants at a spiking level of 2.00 mg kg(-1) was 74.5%.

A survey was conducted on the incidence of fungi, and the natural occurrence of aflatoxins and fumonisins in preharvest maize from fields in south-western Nigeria. Mycological examinations revealed the predominance of F. verticillioides (Zea mays) (syn. F. moniliforme), occurring in 89.3% of samples with a mean kernel infection of 49.4%, while Aspergillus flavus was isolated from 65% of samples having a mean kernel infection of 6.8%. Aflatoxin B1 was detected in 18.4% of samples with a mean of 22 micrograms kg-1, while aflatoxins B2, G1 and G2 were present in 7.8, 2.9 and 1% of the samples with mean levels of 10, 8 and 7 micrograms kg-1, respectively, in contaminated samples. Total aflatoxins ranged from 3 to 138 micrograms kg-1 in positive samples, with a mean of 28 micrograms kg-1. Fumonsin B1 was the predominant toxin detected in terms of frequency (78.6% of samples) and quantity (concentration range 70-1780 micrograms kg-1, mean = 495 micrograms kg-1). Fumonisin B2 was detected in 68 samples (66%) with a mean of 114 micrograms kg-1. Fifteen samples were contaminated with both aflatoxins and fumonisins.

A survey was performed to obtain the frequency and levels of contamination by deoxynivalenol (DON) and fumonisins B1 and B2 (FB1, FB2) mycotoxins in Italian marketed foods. Of 202 samples investigated, including raw materials and processed cereal foods (bread, pasta, breakfast cereals, biscuits, baby and infant foods), 84% were contaminated with DON at levels from 0.007 to 0.930 microg x g(-1) (median 0.065 microg x g(-1)); 26% contained FB1 ranging from 0.010 to 2.870 microg x g(-1) (0.070 microg x g(-1)); 35% contained FB2 at 0.010-0.790 microg x g(-1) (0.080 microg x g(-1)). The highest levels of DON and FB1 were detected in raw cereals and wholemeal flours. The highest levels of FB2 were detected in durum wheat pasta. A widespread DON contamination was found in baby and infant foods at levels varying from 0.007 to 0.166 microg x g(-1).

Twenty-five samples of retail corn flakes (from 15 lots) were analysed for fumonisin B(1) (FB(1)) and fumonisin B(2) (FB(2)). They were detected in 22 and 12 samples, respectively, at respective mean concentrations 68 and 8 ng g(-1). Samples were extracted with methanol-acetonitrile-water (25:25:50) and there was an excellent correlation for FB(1) between results obtained with C(18) clean-up and those obtained with the immunoaffinity column (IAC) clean-up. After extraction of the corn flakes' residue with 1% sodium dodecyl sulphate (SDS) solution and hydrolysis with 2 N potassium hydroxide, hidden (protein bound) fumonisin was determined as HFB(1), which was found in residues from all the corn flakes samples, even those containing no detectable FB(1); the average concentration of HFB(1) was 101 ng g(-1), equivalent to 180 ng FB(1) g(-1). Thus, our results showed an average of 2.6 times more FB(1) present in bound form as was determined by conventional analysis. We found a correlation coefficient of -0.5034 for a logarithmic relationship between the FB(1) (C(18) clean-up) and HFB(1) concentrations The highest concentration of HFB(1) formed was 288 ng g(-1) from a sample containing only 12-15 ng FB(1) g(-1), while the lowest concentration of HFB(1) was 26 ng g(-1) from a sample with 152-155 ng FB(1) g(-1). This low degree of correlation should be taken into account by food safety authorities in estimates of human exposure to protein bound fumonisin.

The effect of storage on mycoflora profile was monitored bimonthly in 36 corn (Zea mays L.) samples, dividing the same sample into groups dried to 11 and 14% moisture content (1008 analysis). These groups were further subdivided based on the initial total count (moulds and yeasts) up to 10(4) CFU g(-1) (12 samples, range 1.6 x 10(4) to 9.0 x 10(4), mean 3.8 x 10(4) CFU g(-1)) and up to 10(5) CFU g(-1) (24 samples, range 1.0 x 10(5) to 5.0 x 10(5), mean 2.7 x 10(5) CFU g(-1)). In the corn group dried to 11%, the fumonisin content was analysed at the initial stage (freshly harvested) and at the end of 12-month storage. Fusarium spp. and Penicillium spp. prevailed at the freshly harvested stage (100%), maintaining this profile throughout 12 months, in corn dried to both 11 and 14%. Cladosporium spp., Aspergillus spp. and Phoma spp. were also detected at lower frequencies during the storage. Fusarium spp. and the total fungal colony count during 12-month storage carried out with samples dried to 11 or 14% moisture content were statistically evaluated using ANOVA for randomized complete block design. The correlation between storage time and Fusarium spp. and total fungal colony count data was analysed by Pearson's correlation test. There was no difference in Fusarium spp. and total counts in the 10(4) CFU g(-1) initial total count group throughout the storage time (p < 0.05). There was a negative correlation between fungal population and storage time (p < 0.05) in the 10(5) CFU g(-1) initial total count group. Fumonisins were detected in all freshly harvested corn, at a mean concentration of 9.9 +/- 6.0 micro g g(-1) (range 0.74-22.6 micro g g(-)1). These values did not change in the 12-month stored corn (mean of 9.9 +/- 5.8 micro g g(-1), range 0.81-23.7 micro g g(-1)). These post harvest data indicated the importance of moisture content at the crop harvesting/predrying stage to control fungal growth and further fumonisin production.

A survey for aflatoxin B1 (AFB1), fumonisin B1 and ochratoxin A (OTA) was conducted on 127 samples that included 30 food-grade barley, 32 barley foods, 18 food-grade corn and 47 corn foods, randomly collected during 1998-99 in Seoul, Korea. The presence of mycotoxins was analysed by direct competitive enzyme-linked immunosorbent assay (ELISA), and most of the positive samples from ELISA were confirmed using high-performance liquid chromatography (HPLC). Recoveries of AFB1 and OTA spiked at 10 ng g(-1) and FB1 spiked at 50 ng g(-1) were 106, 87 and 105% by ELISA, whereas those by HPLC were 80, 79 and 84%, respectively. Detection limits by ELISA for AFB1, FB1 and OTA were 1, 5 and 5 ng g(-1), and those by HPLC were 0.6, 35 and 1 ng g(-1). Naturally occurring AFB1, FB1 and OTA were found in 4/32 (12%), 2/32(6%) and 4/32 (12%) samples of barley foods with an average of 26, 16 and 9 ng g(-1), respectively. AFB1 and FB1 in corn foods were detected in 4/47 (8%) and 9/47 (19%) samples with the average being 20 and 74 ng g(-1), while no OTA was found in any corn foods samples. No AFB1, FB1 or OTA was detected in any of food-grade barley and corn samples. This is the first report on the natural co-occurrence of AFB1 and FB1 in barley and corn foods as well as on surveillance of OTA in Korea.