Comparison of methods and optimisation of the analysis of fumonisins B1 and B2 in masa flour,an alkaline cooked corn product

A comparison study of different extraction and clean-up procedures for the liquid chromatographic analysis of fumonisins B₁ (FB₁) and B₂ (FB₂) in corn masa flour was performed. The procedures included extraction (heat or room temperature) with acidic conditions or EDTA-containing solvents, and clean-up by immunoaffinity or C18 solid-phase extraction columns. Thereafter an analytical method was optimised using extraction with an acidic mixture of methanol–acetonitrile–citrate/phosphate buffer, clean-up through the immunoaffinity column and determination of fumonisins by liquid chromatography with automated pre-column derivatisation with o-phthaldialdehyde reagent. Recovery experiments performed on yellow, white and blue masa flours at spiking levels of 400, 800 and 1200?µg?kg^?1 FB₁ and of 100, 200 and 300?µg?kg^?1 FB₂ gave overall mean recoveries of 99% (±6%) for FB₁ and 88% (±6%) for FB₂. Good recoveries (higher than 90% for both FB₁ and FB₂) were also obtained with corn tortilla chips. The limits of quantification of the method (signal-to-noise ratio of 10) were 25?µg?kg^?1 for FB₁ and 17?µg?kg^?1 for FB₂. The method was tested on different commercial corn masa flours as well as on white and yellow corn tortilla chips, showing fumonisin contamination levels (FB₁?+?FB₂) up to 1800?µg?kg^?1 (FB₁?+?FB₂) in masa flour and 960?µg?kg^?1 in tortilla chips. Over 30% of masa flours originating from Mexico exceeded the European Union maximum permitted level.     

Fumonisin B1 in cereal mixtures marketed in Brazil

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.     

Co-contamination of aflatoxin B1 and fumonisin B1 in food and human dietary exposure in three areas of China

Aflatoxins and fumonisins are ubiquitous foodborne toxicants and the co-occurrence of these mycotoxins in human foods represents a significant public health concern, which has been strongly associated with human aflatoxicosis, neural tube defects, as well as many types of primary cancers. In this study the co-contamination of aflatoxin B₁ (AFB₁) and fumonisin B₁ (FB₁) in food and human dietary exposure was investigated in residents of three different areas of China. A total of 209 food samples were measured for AFB₁ and FB₁. The median AFB₁ levels were 13.5, 2.3 and 1.3?µg?kg^?1 and the median FB₁ levels were 2.6, 0.4 and 0.3?mg?kg^?1 in corn samples collected from Huaian (a high-risk area for oesophageal cancer), Fusui (a high-risk area for liver cancer) and Huantai (a low-risk area for both oesophageal and liver cancers), respectively. The median level of AFB₁ in plant oil of Fusui was the highest (52.3?µg?kg^?1) among all food samples analysed. Co-contamination of these two mycotoxins was found in corn, rice and wheat flour. Based on measured food consumption data, the averaged daily dietary intake of AFB₁ was 0.397?µg (range?=?0.269–1.218?µg) in residents of Huantai, 1.723?µg (0.224–49.772?µg) in Huaian, and 2.685?µg (1.006–14.534?µg) in Fusui. The averaged FB₁ daily dietary intake was 92.4?µg (range?=?55.0–362.1?µg) for residents of Huantai, 460.0?µg (83.2–2894.5?µg) in Huaian, and 138.6?µg (30.0–10,541.6?µg) in Fusui. These data suggest that the co-exposure to AFB₁ and FB₁ in residents of rural China may contribute to the aetiology of human chronic diseases in high-risk areas.     

Fumonisins B1, B2 and B3 in corn products,wheat flour and corn oil marketed in Shandong province of China

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.     

Fusarium infection of maize and maize-based products and exposure of a rural population to fumonisin B1 in Limpopo Province,South Africa

Fusarium species (spp.) and fumonisin B₁ (FB₁) contaminations were monitored in maize and porridge consumed by a rural population of Limpopo Province, South Africa. Faecal samples were also analysed for FB₁ as a means of estimating the degree of dietary exposure to this mycotoxin. In total, 142 samples of maize (n?=?54), porridge (47) and faeces (41) were screened for Fusarium spp. using a serial dilution technique followed by DNA sequencing, while FB₁ was further screened and quantified by thin-layer chromatography (TLC) and high-performance liquid chromatography (HPLC), respectively. At least four species of Fusarium were identified, of which F. verticillioides was the most prevalent in all three sample types analysed. The contamination levels of FB₁ were significantly higher in 87% of maize sampled (range?=?101–53,863?µg?kg^?1) as compared with porridge (74% incidence rate; range?=?0.2–20?µg?kg^?1) and faecal samples (100% incidence rate; range?=?0.3–464?µg?kg^?1). Thus, it can be deduced that the level of human exposure to FB₁ via the consumption of maize was high as several samples contained levels exceeding 1000?µg?kg^?1, which was strongly supported by the levels found in faecal samples. Further data revealed that a high proportion of FB₁ is destroyed or removed by processing maize into porridge. As maize porridge is consumed as a staple, the low levels found provide a means to limit exposure to FB₁. Levels of FB₁ found in the faeces which were higher indicate that other foods contaminated with the toxin are also consumed.     

Occurrence of fumonisins and aflatoxins in cereals from markets of Hebei province of China

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.     

Fumonisin B1 and B2 occurrence in dried fig fruits (Ficus carica L.) under Meander Valley's climatic conditions and relationship with fruit quality

Fusarium is the agent causing endosepsis (internal rot) in fig fruits and it is widespread in fig orchards in the Aegean region. This research was conducted to determine the natural occurrence of fumonisin B₁ (FB₁) and B₂ (FB₂) on dried fig fruits of Sarilop (syn. Calimyrna) variety which are mainly grown in the Big and Small Meander Basins in the Aegean region, representing 60% of world dried fig production. A total of 262 samples belonging to two quality classes, Class A and Class cull, were collected from 12 different locations during the two crop years in 2004 and 2005. The fumonisin detection method is based on extraction with methanol–acetonitrile–water, derivatization with o-phthaldehyde and quantification by reversed-phase high-performance liquid chromatography with fluorescence detection. The mean concentrations of FB₁ and FB₂ in fumonisin-positive samples were 0.080?±?0.047?µg?g^?1 and 0.055?±?0.031?µg?g^?1 and ranged from LOD to 0.332?µg?g^?1 and from LOD to 0.198?µg?g^?1, respectively. The incidence of fumonisins significantly differed between the two crop years. This difference can be attributed to the alteration in the rainfall regime from mid-May to mid-August (7.2?mm in 2004, 90.9?mm in 2005) and number of humid wind currents from a westerly direction (183 in 2004, 492 in 2005) from the end of July and mid-August that may have triggered a higher incidence of Fusarium spp. and thus fumonisin production.     

Transfer of aflatoxin B1 and fumonisin B1 from naturally contaminated raw materials to beer during an industrial brewing process

The aim of this research was to determine the fate of aflatoxins (AFs) and fumonisins (FBs) naturally occurring in raw materials (maize grit and malted barley) during four industrial brewing processes. The aflatoxin B₁ (AFB₁) level in raw materials varied from 0.31 to 14.85 µg kg^?1, while the fumonisin B₁ (FB₁) level (only in maize grit) varied from 1146 to 3194 µg kg^?1. The concentration in finished beer ranged from 0.0015 to 0.022 µg l^?1 for AFB₁ and from 37 to 89 µg l^?1 for FB₁; the other aflatoxins and fumonisin B₂ were not found in beer samples. The average percentage of toxins recovered in finished beer, referring to the amounts contained in raw materials, were 1.5% ± 0.8% for AFB₁ and 50.7% ± 4.7% for FB₁. These results were mainly due to the different solubility of the two mycotoxins during the mashing process. If raw materials comply with the limits fixed by European Commission Regulations, the contribution of a moderate daily consumption of beer to AFB₁ and FB₁ intake does not contribute significantly to the exposure of the consumer.     

Fumonisins B1 and B2 in the corn-milling process and corn-based products,and evaluation of estimated daily intake

The distribution of fumonisins (FBs: FB₁ and FB₂) in the corn-milling process and in corn-based products, as well as daily intake estimates for the Brazilian population were evaluated. Among corn fractions samples, corn meal had the highest mean concentration of FB₁ (1305 µg kg^?1) and FB₂ (651 µg kg^?1) and a distribution factors of 452% and 256% in relation to corn grain, respectively. On the other hand, the distribution factor of FB₁ and FB₂ in corn flour was found to be 144% and 88% respectively, which demonstrates that fumonisins in this fraction were reduced compared with corn grain. As a result, almost half the corn meal samples (47%) would be non-compliant with future Brazilian regulation (2017) for fumonisins. However, corn-based products, such as corn flakes and popcorn, were in compliance with the regulation. The average probable daily intake and maximum probable daily intake of fumonisins estimated for the Santa Catarina state (Brazil) population were below the provisional maximum tolerable daily intake of 2 µg kg^?1 body weight day^?1 for all corn samples. Despite this, the adoption of practices to control the occurrence of fumonisins should be applied to the corn-milling fractions that may contain a higher concentration of this toxin, such as corn meal, often used for animal feed in Brazil.     

Occurrence and intake of deoxynivalenol in cereal-based products marketed in Korea during 2007–2008

The occurrence of deoxynivalenol (DON) was investigated in 514 cereal-based products (corn-based, n = 125; barley-based, n = 96; wheat-based, n = 94; rice-based, n = 199) marketed in Korea during 2007?2008, and estimates of DON intake were determined. Samples were analysed by high-performance liquid chromatography (HPLC) with ultraviolet light (UV) detection after immunoaffinity clean-up. The limits of detection (LOD) and limits of quantification (LOQ) were 2.2 and 5.6 µg kg^–1, respectively. Recoveries and repeatability expressed as coefficients of variation (CV) were 82.3–100% and 2.4–15.3% in beer, bread and dried corn. The incidences and mean levels of DON were 56% and 68.9 µg kg^?1 for corn-based products, 49% and 24.1 µg kg^?1 for wheat-based products, 43% and 7.5 µg kg^?1 for barley-based products, and 16% and 3.4 µg kg^?1 for rice-based products, respectively. The estimated daily intake of DON from the consumption of rice-based, wheat-based, barley-based and corn-based products were 0.0038 µg kg^?1 bw day^?1, 0.0032 µg kg^?1 bw day^?1, 0.0015 µg kg^?1 bw day^?1 and 0.0002 µg kg^?1 bw day^?1, respectively. These values represent 0.38%, 0.32%, 0.25% and 0.01% of the provisional maximum tolerable daily intake (PMTDI) of 1 µg kg^?1 bw day^?1. These results indicate that rice-based products are major contributors to DON exposure in Korea, even though the current exposure level is unlikely to cause adverse health effects.     

Distribution of aflatoxins and fumonisins in dry-milled maize fractions

The aim was to evaluate the distribution of aflatoxins and fumonisins in fractions derived from the dry-milling of contaminated maize. Two maize lots with different contamination levels were processed and sampled: the first (maize 1) had aflatoxin B₁ (AFB₁) and fumonisin B₁ (FB₁) levels of 3.6 and 5379 µg kg^?1, respectively; the second (maize 2) had corresponding levels of 91.1 and 8841 µg kg^?1, respectively. The cleaning step reduced AFB₁ and FB₁ levels by 8 and 11% in maize 1 and by 57 and 34% in maize 2. The subsequent removal of bran and germ led to a further decrease in contamination levels in the products destined for human consumption. In the latter, AFB₁ was uniformly distributed, while FB₁ was concentrated in the finer size fractions. Contamination of raw maize 1 (3.6 µg kg^?1) was below the European Union AFB₁ limit of 5 µg kg^?1 for unprocessed maize, but among the final products only coarse flour (1.7 µg kg^?1) was within the European Union limit of 2 µg kg^?1, while grits and fine flour showed higher levels (2.7 and 2.5 µg kg^?1, respectively). As regards cleaned maize, a different distribution of the two toxins was observed in the kernels: AFB₁ contamination was more superficial and concentrated in germ, while FB₁ contamination affected the inner layers of the kernels.     

Ergot alkaloids in some rye-based UK cereal products

UK rye-based cereal products were analysed for six major ergot alkaloids using an in-house-validated liquid chromatography-tandem mass spectrometry (LC-MS/MS) method that distinguished -ine and -inine epimers (isomers). Ergot alkaloids were detected in 25 of 28 samples subject to quantification limits of 1–3 µg kg^?1, including all of eleven rye crispbreads that had up to 340 µg kg^?1. Continental-style rye breads contained up to 121 µg kg^?1. Loaf breads, bread-mix flours, and crackers contained only low levels of alkaloids. Ergotamine, ergocristine, and ergosine were the predominant ergot alkaloids in terms of level and frequency of occurrence. There were no apparent differences in the ergot levels between the organic and non-organic products, although the numbers tested were low. Most rye breads had a ratio of -ines to -inines of about 1.5, and rye crispbreads had lower and more variable -ine to -inine ratios.     

Fumonisin B2 production by Aspergillus niger from grapes and natural occurrence in must

Aspergillus niger has been recently found to produce fumonisin B₂ (FB₂). Thirty-one strains belonging to four Aspergillus species isolated from grape were evaluated for FB₂ production on agar plates. Four out of eight strains of A. niger produced FB₂ (29–293 µg g^?1). None of the strains of A. uvarum (n = 7), A. tubingensis (8) and A. carbonarius (8) produced detectable amounts of toxin. The capability to produce FB₂ was also confirmed by some A. niger strains artificially inoculated on grape berries. Natural occurrence of FB₂, at levels of 0.01 and 0.4 µg ml^?1, was found in two samples of must collected in Apulian cellars in 2007. This is the first report of FB₂ contamination in must. These findings suggest that there is a potential risk of exposure to FB₂ in the grape–wine chain for consumers and that A. niger may represent the major fumonisin-producing species among black Aspergilli occurring on grapes.     

Mycotoxicological quality evaluation of corn samples used by processing industries in the Northern region of Paraná State,Brazil

Based on fungal and fumonisin contamination of 870 freshly harvested samples, the quality of corn used by processing industries in the Northern region of Paraná State, Brazil (2003 and 2004 crop-year) was evaluated. Sampling was carried out for each crop at two points in the production chain, i.e. at reception by the processors and at the pre-drying step. Corn samples were more frequently contaminated with Fusarium sp. (100%) and Penicillium sp. (84.1–95.3%) than Aspergillus sp. (5.6–19.8%). Fumonisin B₁ (FB₁) was detected in all samples from the two points in both crop-years. FB₁ levels ranged 0.02–11.83 µg g^?1 in the reception and 0.02–10.98 µg g^?1 in the pre-drying samples of the 2003 crop. Samples from the 2004 crop showed FB₁ levels ranging 0.03–12.04 µg g^?1 in the reception and 0.06–7.74 µg g^?1 in the pre-drying samples. FB₂ levels ranged 0.02–5.25 µg g^?1 in the reception and 0.01–7.89 µg g^?1 in the pre-drying samples (2003 crop-year). In samples from the 2004 crop, FB₂ levels ranged 0.02–6.12 µg g^?1 in the reception and 0.05–3.47 µg g^?1 in the pre-drying samples. Low fumonisin levels were detected in most corn samples used by processors in the Northern region of Paraná State, showing a decreasing trend in fumonisin contamination over the years.     

Aflatoxins,ochratoxin A and zearalenone in Brazilian corn cultivars

Past surveys indicated that the occurrence of aflatoxins, zearalenone and ochratoxin A was not a problem in corn and corn products in the state of São Paulo, Brazil. However, according to recent studies, a change in pattern has been detected. To obtain a better overview, these toxins were searched for in 110 samples of freshly harvested corn, corresponding to 48 commercial cultivars planted at three different locations in the state. Aflatoxin contamination was found in 60 (54.5%) of the samples, in levels ranging from 6 to 1600 µg kg^?1 aflatoxin B₁. Insect control was exercised, so this was not the main route of corn infection. Endosperm type, germplasm type, number of days to flowering, and length of time the mature corn remained in the field had no effect on aflatoxin contamination. Ochratoxin A was found in two samples (206 and 128 µg kg^?1) and zearalenone in one sample (4640 µg kg^?1). Possible causes of the increase in aflatoxin levels may lie in the changing nature of the commercial cultivars employed, associated with the forsaking of the original landraces, and in a change in the toxigenicity pattern of the corn mycoflora Aspergillus flavus/Aspergillus parasiticus prevailing strains. © 2001 Society of Chemical Industry     

Formation of fumonisins and other secondary metabolites by Fusarium oxysporum and F. proliferatum: a comparative study

The principal aim of this study was to estimate the formation of fumonisins (FB₁ and FB₂), moniliformin (MON), and ergosterol (ERG) by Fusarium oxysporum and Fusarium proliferatum, while the formation of beauvericin (BEA) was estimated by the latter Fusarium species only. Moreover, the effect of temperature on the biosynthesis of mycotoxins was also evaluated. Fumonisins were formed by F. proliferatum, with the highest yield at 18°C (720.0–1976.6 µg g^?1 for FB₁, 74.2–670.8 µg g^?1 for FB₂) and only by three of four F. oxysporum strains at a very low level (0.02–4.77 µg g^?1 for FB₁, 0.02–2.15 µg g^?1 for FB₂). The amount of MON formed by F. proliferatum was the highest (p < 0.001) at 32°C (3056.87 µg g^?1), while MON biosynthesis by F. oxysporum was lower 227.54 µg g^?1 (p < 0.001). BEA was produced by F. proliferatum with the highest level at 25°C (p < 0.001). ERG–recognized as an indicator of fungal biomass development and as a consequence of mycotoxin formation–was found at the highest concentration at a biosynthesis temperature of 25°C for F. proliferatum and F. oxysporum (p < 0.001).     

Occurrence of Fusarium mycotoxins in maize imported into the UK, 2004–2007

This study examined a total of 82 consignments of French and Argentinean raw maize as received at maize mills in the UK between 2004 and 2007. Samples were analysed for deoxynivalenol (DON), nivalenol (NIV), other trichothecenes, zearalenone (ZON), and fumonisins B₁, B₂, and B₃ (FB₁, FB₂, and FB₃) using fully validated analytical methods with limits of quantification of 10 µg kg^?1 for DON, NIV, and each fumonisin mycotoxin and 3 µg kg^?1 for ZON. All samples except two containing fumonisins met the European Commission statutory maximum permissible levels for DON, ZON, and FB₁ + FB₂ as operating in 2007. The maximum concentrations found for DON, NIV, ZON, and FB₁ + FB₂ were 444, 496, 165 and 5002 µg kg^?1, respectively. Fumonisins were detected in almost every sample with 65% of Argentinean maize containing more than 1000 µg kg^?1 of FB₁ + FB₂. In contrast, ZON was not detectable in almost 50% of consignments. During this period there was a distinct difference in mycotoxin concentrations between harvests and geographic origin. Flint maize from Argentina usually contained lower concentrations of DON and related trichothecenes and higher levels of fumonisins than maize from France, although concentrations of fumonisins up to 2000 µg kg^?1 or greater occurred in samples from both regions. The incidence and concentrations of fumonisins were similar to those in a similar previous survey, while zearalenone concentrations were lower. The distribution of mycotoxins in multi-hold ships was also investigated showing that fumonisins were much more evenly distributed than DON, thus indicating their general level in the ship as a whole. The effect of cleaning regimes was found to be very variable, especially for DON, ranging from no removal of mycotoxins to greater than 50% in some instances, but was not related to concentration. Evidence here suggests that while cleaning is essential for removing foreign bodies before milling, it cannot be used as a reliable tool for reducing mycotoxins.     

Natural occurrence of type-B trichothecene mycotoxins in Korean cereal-based products

Type-B trichothecenes (deoxynivalenol (DON), nivalenol (NIV), fusarenone-X (FUS-X), 15-acetyldeoxynivalenol (15ADON), and 3-acetyldeoxynivalenol (3ADON)) were determined in 338 cereal-based products. Detection limit, quantification limit and mean recovery for five toxins were in the ranges 0.7–2.6?µg?kg^?1, 2.1–7.8?µg?kg^?1 and 73–110%, respectively. The range of occurrence and average level in samples were, respectively, 21–88% and 5.2–121.8?µg?kg^?1 for NIV, 10–96% and 1.7–109.5?µg?kg^?1 for DON, 2–39% and 0.4–3.6?µg?kg^?1 for FUS-X, 0–80% and 0–17.3?µg?kg^?1 for 15ADON, and 0–29% and 0–1.5?µg?kg^?1 for 3ADON. Regarding co-occurrence, 64% of samples had more than two type-B trichothecenes. The estimated daily intakes of NIV, DON, FUS-X, 15ADON, and 3ADON were 0.077, 0.048, 0.004, 0.006 and 0.002?µg?kg^?1?bw?day^?1, respectively. These results suggest that current exposure levels do not indicate the possibility of adverse effects, but consideration of the combined exposure of type-B trichothecenes may be required due to the high frequency of co-occurrence.     

Natural occurrence of fumonisins B1 and B2 in corn in four provinces of China

Fumonisin B₁ (FB₁) and fumonisin B₂ (FB₂) are the most abundant fumonisins (FBs) occurring worldwide in maize, infected mainly by Fusarium verticillioides and F. proliferatum. A total of 307 corn kernel samples were collected from 45 districts of Gansu, Shandong, Ningxia and the Inner Mongolia provinces of the north and northwest China. The samples were analysed for FB₁ and FB₂ by high-performance liquid chromatography. The FBs (FB₁+ FB₂) incidence rate in samples from Gansu, Shandong, Ningxia and Inner Mongolia were 31.5%, 81.1%, 46.2% and 53.6%, respectively. Average FBs concentration was 703 μg/kg and the concentrations ranged from ≤11 to 13,110 μg kg^?1. Results were compared with the European Commission (EC) regulation for FB₁+ FB₂ in unprocessed maize for human consumption of 4 mg kg^?1. Contamination in 17 samples was higher than these levels. More than 80% of the samples from Liaocheng county, which is located in the Shandong province, were contaminated with FBs, with a mean total FB concentration of 2496 μg/kg. The result was significantly different from that of the Inner Mongolia (1399 μg/kg), Ningxia (373 μg/kg) and Gansu (175 μg/kg). Average exposure to FBs (0.12 μg/kg body weight/day) is within the provisional maximum tolerable daily intake of 2.0 mg/kg of body weight set by the Joint Food and Agriculture Organization and World Health Organization Expert Committee on Food Additives.     

Occurrence of certain mycotoxins in corn and corn‐based products and thermostability of fumonisin B1 during processing

A total of 57 samples of corn and corn‐based products collected from various districts of Egypt were analyzed for Fusarium mycotoxins (T‐2, diacetoxyscripenol (DAS( deoxynivalenol (DON) and fumonisin B₁ (FB₁) and aflatoxins. FB₁ was detected in about 80%, 53.85%, 33.3%, and 28.57% of yellow corn, corn meal, white corn, and popcorn samples, respectively. The levels of FB₁ ranged from 10 to 780 μg/kg. T‐2 and DAS were detected in 5% and 10% of yellow corn samples, respectively, and DON was detected in white corn and popcorn samples at levels of 28.8 and 10.1 μg/kg, respectively. Starch samples were found to be free from Fusarium mycotoxins. Baking balady bread at 450°C/min reduced FB₁ to 72.4% while baking Franco bread at 250°C/20 min reduced FB₁ to 57.4%. Boiling of macaroni and corn in water completely removed FB₁ from contaminated samples. On the other side, corn flakes samples were found to be contaminated with aflatoxins B₁ and G₁ at levels ranging from 6 to 10 ppm, whereas 2.9% of samples were contaminated with aflatoxin B₁ > 35 ppm and G1 > 16 ppm.