Natural Occurrence of 16 Fusarium Toxins in Grains and Feedstuffs of Plant Origin from Germany

A total of 220 samples comprising cereals, cereal byproducts, corn plants and corn silage as well as non-grain based feedstuffs was randomly collected during 2000 and 2001 from sources located in Germany and analysed for 16 Fusarium toxins. The trichothecenes scirpentriol (SCIRP), 15-monoacetoxyscirpenol (MAS), diacetoxyscirpenol (DAS), T-2 tetraol, T-2 triol, HT-2 and T-2 toxin (HT-2, T-2), neosolaniol (NEO), deoxynivalenol (DON), 3-acetyldeoxynivalenol (3-ADON), 15-acetyldeoxynivealenol (15-ADON), nivalenol (NIV) and fusarenon-X (FUS-X) were determined by gas chromatography/mass spectrometry. Zearalenone (ZEA) and α- and β-zearalenol (α- and β-ZOL) were analysed by high performance liquid chromatography with fluorescence and UV-detection. Detection limits ranged between 1 and 19 μg/kg. Out of 125 samples of a group consisting of wheat, oats, corn, corn byproducts, corn plants and corn silage only two wheat samples did not contain any of the toxins analysed. Based on 125 samples the incidences were at 2–11% for DAS, NEO, T-2 Triol, FUS-X, α- and β-ZOL, at 20–22% for SCIRP, MAS, T-2 tetraol and 3-ADON, at 44–74% for HT-2, T-2, 15-ADON, NIV and ZEA, and at 94% for DON. Mean levels of positive samples were between 6 and 758 μg/kg. Out of 95 samples of a group consisting of hay, lupines, peas, soya meal, rapeseed meal and other oilseed meals, 64 samples were toxin negative. DAS, T-2 triol, NEO and FUS-X were not detected in any sample. The incidences of DON and ZEA were at 14 and 23% respectively, those of the other toxins between 1–4%, mean levels of positive samples were between 5 and 95 μg/kg.     

Trichothecene production and the relationship to vegetative compatibility groups in shape Fusarium poae

Twenty-two Norwegian and two Polish isolates of Fusarium poae were cultured on rice and in two liquid media, MOSS and MYRO. All samples were analysed for trichothecenes by gas chromatography mass-spectrometer. Association of trichothecene production with vegetative compatibility groups was studied in the F. poae isolates. Twenty of the isolates produced the type A trichothecenes diacetoxyscirpenol or monoacetoxyscirpenol in at least one of the media, in the concentration range of 0.01 to 65 μg ml^-1 in the liquid culture and 0.1 to 67 μg g^-1 on rice. The other group of trichothecenes detected were of type B; nivalenol and its two acetyl-derivatives 4-acetylnivalenol and diacetylnivalenol. Twelve of the strains produced at least one of these metabolites in the concentration range of 0.01 to 7 μg ml^-1 in the liquid culture and 0.1 to 18 μg g^-1 on rice (sum of nivalenol and its acetylated derivatives). A significant correlation was observed between the two groups of toxins (logarithm). None of the isolates produced T-2 or HT-2 toxin. In a previous study these isolates were divided into 13 vegetative compatibility groups. Significant variation in the trichothecene production was observed between different vegetative compatibility groups, but also to some extent within the same group. This revised version was published online in August 2006 with corrections to the Cover Date.     

Occurrence of trichothecenes, zearalenone and ochratoxin A in cereals and mixed feed from central Lithuania

A total of 92 samples — 23 winter wheat, 12 summer barley, 5 oats and 52 mixed feed — were collected from a state factory in Kaunas, Lithuania and were analysed for the presence of trichothecenes, zearalenone (ZEN) and ochratoxin A (OA) using gas chromatography with electron capture detection and immunoaffinity column/high performance liquid chromatography with fluorescence and UV detections. Deoxynivalenol (DON), nivalenol (NIV), T-2 toxin and HT-2 toxin were detected at concentrations above 10 μg/kg in 68%, 48%, 38% and 8% of cereal samples, respectively, and in 98%, 88%, 12% and 8% of samples of mixed feed for swine and poultry. More than 10 μg/kg of zearalenone and ochratoxin A were found in 58% and 92% of the mixed feed samples, respectively. The highest concentrations of all analysed trichothecenes in Lithuanian mixed feed and cereal grains, with an exception of T-2 toxin in one oat lot and one sample of mixed feed and OA in two mixed feed samples, were lower than those reported as Lithuanian advisory or tolerance limits.     

Trichothecene-induced cytotoxicity on human cell lines

Trichothecene cytotoxicity of type A (T-2 toxin and HT-2 toxin), type B (deoxynivalenol, DON, and nivalenol, NIV), and type D (satratoxins G and H) compounds was determined comparatively by using eight permanent human cell lines (Hep-G2, A549, CaCo-2, HEp-2, A204, U937, RPMI 8226, and Jurkat). Viability of cells was measured by a water-soluble tetrazolium (WST-1) reagent cell proliferation assay assessing mitochondrial metabolic activity. Toxicity was expressed as the toxin concentration inhibiting 50% of cell viability (IC₅₀). Depending on the chemotype of the tested trichothecenes, relative cytotoxic activity differed by a factor of 100–1,000, and the corresponding IC₅₀ values were in the range from 2.2 nmol/l (satratoxin H on Jurkat and U937 cells) to 4,900 nmol/l (deoxynivalenol on HEp-2 cells). In contrast, the specific toxicity of each individual mycotoxin towards different cell lines was within remarkable close limits, and between-cell line differences were much smaller than previously reported. For the cell lines tested, IC₅₀ values were 4.4–10.8 nmol/l for T-2 toxin, 7.5–55.8 mol/l for HT-2 toxin, 600–4,900 nmol/l for DON, 300–2,600 nmol/l for NIV, and 2.2–18.3 nmol/l for satratoxins G/H. In addition, for the first time, the toxic activity of trichothecenes on primary cell culture of human endothelial cells (HUVEC) was tested. The susceptibility of this cell line was comparable to the other cell lines tested, with IC₅₀ values ranging from 16.5 nmol/l (T-2 toxin) to 4,500 nmol/l (DON). The results suggest that the current focus of cytotoxicological studies on trichothecenes on lymphoid cell lines may lead to an underestimate of their potential on other target cell systems.     

T-2 and HT-2 toxin analysis in cereals and cereal products following IAC cleanup and determination via GC-ECD after derivatization

The authors present a new and sensitive method for the determination of T-2- und HT-2 Toxin in cereals and cereal products in the low ppb level. A representative part of the cereal sample is extracted with a mixture of methanol-water (90:10) and the extract is cleaned on the commercially available immunoaffinity column T-2test™ (IAC), eluted with methanol, derivatized by pentafluorpropionic anhydride (PFPA) and measured on a GC-ECD. The method has been successfully validated on wheat, rye and oats. The recovery rates with wheat and rye endowed on a level of 50 ppb and with 85 ppb naturally contaminated oats were 71–115% with a coefficient of variation of 5.7–19.5%. The detection limits of the method with a signal to noise level of 3:1 were 1.5–2.3 μg/kg for HT-2 and 1.1–1.7 μg/kg for T-2 toxin. Financial support: Federal Ministry of Food and Agriculture (part of the project 05HS 001 — Improvement and validation of type A trichothecene (T-2 toxin and HT-2 toxin) analysis and occurrence of these mycotoxins in food marketed in Germany)     

Characterization of natural variation for zinc, iron and manganese accumulation and zinc exposure response in Brassica rapa L.

Brassica rapa L. is an important vegetable crop in eastern Asia. The objective of this study was to investigate the genetic variation in leaf Zn, Fe and Mn accumulation, Zn toxicity tolerance and Zn efficiency in B. rapa. In total 188 accessions were screened for their Zn-related characteristics in hydroponic culture. In experiment 1, mineral assays on 111 accessions grown under sufficient Zn supply (2 μM ZnSO₄) revealed a variation range of 23.2–155.9 μg g⁻¹ dry weight (d. wt.) for Zn, 60.3–350.1 μg g⁻¹ d. wt. for Fe and 20.9–53.3 μg g⁻¹ d. wt. for the Mn concentration in shoot. The investigation of tolerance to excessive Zn (800 μM ZnSO₄) on 158 accessions, by using visual toxicity symptom parameters (TSPs), identified different levels of tolerance in B. rapa. In experiment 2, a selected sub-set of accessions from experiment 1 was characterized in more detail for their mineral accumulation and tolerance to excessive Zn supply (100 μM and 300 μM ZnSO₄). In this experiment Zn tolerance (ZT) determined by relative root or shoot dry biomass varied about 2-fold. The same six accessions were also examined for Zn efficiency, determined as relative growth under 0 μM ZnSO₄ compared to 2 μM ZnSO₄. Zn efficiency varied 1.8-fold based on shoot dry biomass and 2.6-fold variation based on root dry biomass. Zn accumulation was strongly correlated with Mn and Fe accumulation both under sufficient and deficient Zn supply. In conclusion, there is substantial variation for Zn accumulation, Zn toxicity tolerance and Zn efficiency in Brassica rapa L., which would allow selective breeding for these traits.     

Mycotoxin production of <Emphasis Type="Italic">Fusarium langsethiae</Emphasis> and <Emphasis Type="Italic">Fusarium sporotrichioides</Emphasis> on cereal-based substrates

The present study investigated and compared the mycotoxin production of two Fusarium species, F. sporotrichioides and F. langsethiae, isolated from grain samples. Fusarium strains were cultivated at 25°C for 7 days on two types of solid media, i.e. rice-flour and cereal-flour agar. Toxins produced were measured after the incubation period with a multi-mycotoxin method based on liquid chromatography–tandem mass spectrometry (LC-MS/MS). Both F. sporotrichioides and F. langsethiae synthesised type-A trichothecenes, i.e. T-2 and HT-2 toxins, diacetoxyscirpenol (DAS) and neosolaniol (NEO). In addition, both species could be verified as beauvericin producers. The toxin production occurred in both cereal-based assays but was more predominant on the carbohydrate-rich rice-flour medium. The two species were potent producers of T-2 toxin, the highest amounts measured being at a level of 20,000 μg/kg after 7 days’ incubation. Differences between the species were observed regarding the quantitative production of the other trichothecenes: F. sporotrichioides was a more prolific producer of HT-2 toxin and beauvericin, whereas F. langsethiae produced higher amounts of DAS and NEO. On rice-flour assay, the toxin production was monitored during the growth period. The production started rapidly at an early growth phase and several toxins could be detected already after the 1st day of incubation, the highest concentrations being at mg/kg level. The results also indicated that the biosynthesis by F. sporotrichioides and F. langsethiae shifted towards the other type-A trichothecenes at the expense of T-2 toxin at the end of the cultivation.     

Electrical activity in the vagus nerves and some medullary nuclei in rats: Changes induced by endotoxin action and hyperthermia evoked by an increase in ambient temperatures

Acute experiments on rats showed that intraperitoneal administration of 5 μg/kg of a bacterial toxin (pyrogenal) increases the afferent impulsation frequency in the cervical segments of vagus nerves, VN (multifiber recording), and frequency of the multineuronal activity in the solitary tract nucleus (STN); these changes were observed during the whole period of recording (10–160 min following toxin injection). Enhancement of the efferent impulsation in the VN and neuronal activity in the dorsal nucleus of the vagus nerve (DNVN) could be observed only 120–130 min after toxin administration. Under these conditions rectal temperature in experimental animals was 1.5° higher than that in control rats throughout the period of recording. Following subdiaphragmatic vagotomy, the afferent impulsation frequency in the cervical VN decreased about four times and kept on decreasing during the whole period of registration. Pyrogenal introduction evoked no changes in the direction of reactions to vagotomy. Under these conditions, body temperature of these animals was 2.5°C higher than in control vagotomized rats by the final stage of recording. Animal heating in a chamber caused no changes in the afferent impulsation frequency and resulted in a decrease in the frequency of VN efferent discharges. Involvement of the VN in the maintenance of temperature homeostasis during fever induced by the endotoxin action and by hyperthermia due to a rise in ambient temperature is discussed. Neirofiziologiya/Neurophysiology, Vol. 32, No. 2, pp. 112–119, March–April, 2000.     

Fusarium mycotoxins in forage maize — Detection and evaluation

The deoxynivalenol concentrations found in forage maize ranged between 0.24 and 14.29 mg/kg DM (detected by ELISA). When highly contaminated samples were analysed for deoxynivalenol by HPLC or LC-MS the resulting concentrations were in the mean about 50% lower. Furthermore, using LC-MS other type-A and type-B trichothecenes, zearalenone and α-zearalenol were found in these samples. The differences between ELISA and HPLC/LC-MS data for deoxynivalenol are assumed to result from cross-reactions of other trichothecenes with the antibodies used in ELISA and toxin losses from sample purification procedures needed for HPLC and LC-MS analysis. Presented at the 26^th Mykotoxin-Workshop in Herrsching, Germany, May 17–19, 2004     

Mycotoxin production in a carbendazim-resistant strain of fusarium sporotrichioides

Mycelial yield and production of three trichothecenes, namely T-2 toxin, diacetoxyscirpenol (DAS) and neosolaniol (NEO) were compared in control (CS) and carbendazim-resistant strains (RS) ofFusarium sporotrichioides. Each strain was exposed to graded concentrations of carbendazim (0, 1, 2, and 4 μg/ml media) for 2, 5 and 7 days under shake-culture conditions at an incubation temperature of 25°C. Mycelial yield was significantly (P<0.001) affected by strain, carbendazim concentration and incubation time. The strain differences in mycelial mass at 2 days (P<0.05) became more pronounced at 5 and 7 days of incubation (P<0.001). However, mycelial growth differences between the two strains were greatest following exposure to carbendazim, with the effects becoming more divergent with time. Combined results for the three incubation times showed dose related effects in carbendazim inhibition of T-2 toxin production by CS isolates. In contrast, RS cultures exposed to the 2 μg/ml addition of carbendazim significantly increased T-2 toxin production (P<0.05 or better). At 1 and 4 μg/ml additions, T-2 toxin inhibition occurred but the effect was less marked than in the CS series. RS yielded more DAS than CS at 5 days (P<0.05) and at 7 days (P<0.01) of incubation. The major component of this strain difference arose from the effects of the 2 μg/ml addition of carbendazim (P<0.01). NEO production was also higher in RS than in CS, with the difference becoming progressively more pronounced from day 5 (P<0.05) to day 7 (P<0.01) of incubation. However, these differences reflected enhanced NEO output with carbendazim addition of 4 μg/ml (P<0.05) in day 5 extracts and of both 2 μg/ml (P<0.01) and 4 μg/ml additions (P<0.05) in day 7 samples. Moreover, the ratio of NEO to T-2 toxin production was affected by an interaction involving incubation time, strain and carbendazim dose (P<0.05 or better). On day 5, this ratio was greater in CS exposed to 2 μg/ml, but at 4 μg/ml, the ratio was higher in RS. It is concluded that carbendazim resistance induced genuine differences in the synthesis of T-2 toxin and NEO. It is suggested that the strain difference may reside in the conversion of NEO to T-2 toxin which may be sensitive to fungicide concentration. This would imply that carbendazim resistance induces changes in the terminal rather than initial phases of trichothecene biosynthesis.     

Sensitive method for determination of DON in cocoa by means of HPLC-techniques

The mycotoxin deoxynivalenol (DON) is one of a group of mycotoxins known as type B trichothecenes and is particularly formed by the mould speciesFusarium graminearum andFusarium culmorum. The frequency of the occurrence of DON in certain raw materials and the concentrations found make it one of the world’s most significant mycotoxin contaminants. Positive findings of the toxin especially have been established in cereal-based foods, as well as in oilseeds. The main objective of this study was to set up a current situation assessment of the possible occurrence of deoxynivalenol in cocoa and cocoa products. As there was no analytical method for determining DON in cocoa and cocoa products, a special method was developed. The applicability and consistency of the method was confirmed by performing recovery assays on various cocoa products. A special post-column derivatisation procedure was developed to increase selectivity and raise sensitivity by a factor of 80. The method was used to test 230 samples for possible DON content, ranging from cocoa beans to cocoa bean shells, nibs, cocoa liquor and cocoa powders through to finished cocoa-based products. The results suggest that DON may occasionally occur in cocoa beans in very low concentrations. Presented at the 29^th Mykotoxin-Workshop, Fellbach, Germany, May 14–16, 2007     

Development of a method for the determination of citrinin in barley,rye and wheat by solid phase extraction on aminopropyl columns and HPLC-FLD

A method for the determination of the mycotoxin citrinin (CT) in rye, wheat and barley is described. The proposed method is based on ethyl acetate extraction, solid phase clean-up (SPE) on aminopropyl columns and reversed phase high performance liquid chromatography with fluorescence detection (RP-HPLC-FLD). The limits of detection and quantification of CT amounted to 0.6–0.9 μg/kg and 1.7– 3.3 μg/kg with mean recovery rates in the range of 77–92% (RSD 4.8–5.5%). This method can also be used for the determination of CT in red-fermented rice. Presented at the 29^th Mykotoxin-Workshop, Fellbach, Germany, May 14–16, 2007     

Characterization and Distribution of the Selected Metals in the Scalp Hair of Cancer Patients in Comparison with Normal Donors

Eighteen metals were estimated in the scalp hair samples from cancer patients (n = 111) and normal donors (n = 113). Nitric acid–perchloric acid wet digestion procedure was used for the quantification of the selected metals by flame atomic absorption spectrophotometry. In the scalp hair of cancer patients, highest average levels were found for Ca (861 μg/g), followed by Na (672 μg/g), Zn (411 μg/g), Mg (348 μg/g), Fe (154 μg/g), Sr (129 μg/g), and K (116 μg/g), whereas in comparison, the dominant metals in the scalp hair of normal donors were Ca (568 μg/g), Zn (177 μg/g), Mg (154 μg/g), Fe (110 μg/g), and Na (103 μg/g). The concentrations of Ca, Cd, Co, Cr, Fe, K, Mg, Mn, Na, Ni, Pb, Sb, Sr, and Zn were notably higher in the hair of cancer patients as compared with normal donors, which may lead to a number of physiological disorders. Strong positive correlations were found in Mn–Pb (0.83), Cd–Cr (0.82), Cd–Li (0.57), Fe–Pb (0.56), and Fe–Mn (0.55) in the hair of cancer patients whereas Na–Cd, Li–Cr, Li–Co, Co–Cd, Li–Cd, Na–Co, Na–Li, Ca–Mg and Na–Cr exhibited strong relationships (r > 0.50) in the hair of normal donors. Principal Component Analysis (PCA) of the data revealed seven PCs, both for cancer patients and normal donors, but with significantly different loadings. Cluster Analysis (CA) was also used to support the PCA results. The study evidenced significantly different pattern of metal distribution in the hair of cancer patients in comparison with normal donors. The role of trace metals in carcinogenesis was also discussed.     

Pigmented Nanoflagellates Grazing on <Emphasis Type="Italic">Synechococcus</Emphasis>: Seasonal Variations and Effect of Flagellate Size in the Coastal Ecosystem of Subtropical Western Pacific

We investigated seasonal variation of grazing impact of the pigmented nanoflagellates (PNF) with different sizes upon Synechococcus in the subtropical western Pacific coastal waters using grazing experiments with fluorescently labeled Synechococcus (FLS). For total PNF, conspicuous seasonal variations of ingestion rates on Synechococcus were found, and a functional response was observed. To further investigate the impact of different size groups, we separated the PNF into four categories (<3, 3–5, 5–10, and >10 μm). Our results indicated that the smallest PNF (<3 μm PNF) did not ingest FLS and was considered autotrophic. PNF of 3–5 μm in size made up most of the PNF community; however, their ingestion on Synechococcus was too low (0.1–1.9 Syn PNF⁻¹ h⁻¹) to support their growth, and they had to depend on other prey or photosynthesis to survive. The ingestion rate of the 3–5 μm group exhibited no significant seasonal variation; by contrast, the ingestion rates of 5–10 and >10 μm PNFs showed significant seasonal variation. During the warm season, 3–5 μm PNF were responsible for the grazing of 12% of Synechococcus production, 5–10 μm PNF for 48%, and >10 μm PNF for 2%. Taken together, our results demonstrate that the PNF of 3–10 μm consumed most Synechococcus during the warm season and exhibited a significant functional response to the increase in prey concentration.     

Ochratoxin A: Contamination of grain

Ochratoxin A was quantitatively monitored in grain extracts by indirect solid-phase enzyme immunoassay with the use of an immobilized conjugate of the toxin with gelatin and polyclonal rabbit antibodies raised against the ochratoxin A-BSA conjugate. This monitoring found that 1.7 to 18.5% of the samples were contaminated with the toxin at a concentration of 25.9–291.7 μg/kg. An analysis of forage grain found ochratoxin A at concentrations of 440-3250 μg/kg.     

Weathering versus atmospheric sources of strontium in ecosystems on young volcanic soils

We used isotopes of Sr to quantify weathering versus atmospheric sources of foliar Sr in 34 Hawaiian forests on young volcanic soils. The forests varied widely in climate, and in lava flow age and texture. Weathering supplied most of the Sr in most of the sites, but atmospheric deposition contributed 30–50% of foliar Sr in the wettest rainforests. A stepwise multiple regression using annual precipitation, distance from the ocean, and texture of the underlying lava explained 76% of the variation in Sr isotope ratios across the sites. Substrate age did not contribute significantly to variation in Sr isotope ratios in the range of ages evaluated here (11–3000 years), although atmospheric sources eventually dominate pools of biologically available Sr in Hawaiian rainforests in older substrates (≥150,000 years). Received: 25 January 1999 / Accepted: 23 June 1999     

Change in striation density and systematics ofCocconeis scutellum var.Ornata (Bacillariophyceae)

Cocconeis scutellum var.ornata Grun. from three localities of Japan was studied. The striation density in 10 μm showed a marked tendency to increase with the decrease of the valve length in both raphe and rapheless valves, and this tendency did not vary with locality or environmental condition. The striation densities of rapheless valves were 4–6 in 10 μm for a valve length of 40μm, 4–6.5 for 30 μm, 6–9 for 20μm and 6.5–11 for 15μm. Those of raphe valves were 10–11 in 10μm for a valve length of 40μm, 10–12 for 30μm, 11–14.5 for 20μm and 12.5–17 for 15μm. According to the range of changing value in striation density obtained by the present study,C. scutellum var.schmidti Frenguelli andC. japonica Schmidt are identical withC. scutellum var.ornata. Dedicated to Prof. Munenao Kurogi on the occasion of his academic retirement. Culture experiment in the present study was undertaken at the Institute of Algological Research, Faculty of Science, Hokkaido University at Muroran.     

Metabolic rate of Arctic charr eggs depends on their parentage

The metabolic rate (specific heat output) of individual eyed-stage eggs of Arctic charr Salvelinus alpinus (Linnaeus, 1758) originating from different families was measured with direct microcalorimetry. Metabolic rates varied between 2.3–7.9 μW ind⁻¹ and 0.06–0.22 μW mg⁻¹. Absolute heat output was unrelated to egg size, but size-scaled or specific heat output was negatively correlated with egg size, measured as diameter, dry mass or fresh mass. Metabolic rates varied significantly between families, suggesting that genetic and/or maternal effects affect embryonic metabolism in Arctic charr. Heat output increased almost linearly from 3.4 to 16.7 μW ind⁻¹ (0.09–0.67 μW mg⁻¹) during the embryonic development. Although the metabolic rate varied between the families and egg metabolic rate increased during development, there was an unexpected disconnect between metabolic rate and hatching time.     

Type-B trichothecene calibrants: Comparison of HPLC and GC-results within an intercomparison study

Within the EC-financed project “Feasibility Study for the Production of Certified Calibrants for the Determination of Deoxynivalenol and other B-Trichothecenes”, an intercomparison study was performed with 13 European participants. Main goals of the intercomparison study were to check the feasibility of a small batch of gravimetrically prepared calibrants, to directly compare common and individually prepared calibrants, to test the practicability of toxin mixtures as calibrant solutions and finally to give recommendations for the means of certification. Additionally, it focused on the comparison of gas chromatography (GC) and high performance liquid chromatography (HPLC) for the determination of pure type-B trichothecene solutions, which is described in this publication. The participating laboratories received calibrant solutions as well as toxin solutions of unknown concentration and employed mainly HPLC-UV; GC-ECD (electron capture detection) and GC-MS (mass spectrometry) methods were used less often. The intercomparison study generally suffered from a high rate of outliers (22% of all the data). Throughout the study, 48% of all GC results were classified as outliers and it soon became apparent, that GC results highly infuenced the outcome of the study and that the used GC methods were not robust enough for the certification of type-B trichothecene calibrants. The high discrepancy between HPLC and GC results in the intercomparison study presumably lies in the crucial step of derivatisation. Presented at the 27^th Mykotoxin-Workshop, Dortmund, Germany, June 13–15, 2005. Financial support: European Commission, Project No. GRD1-2002-70018     

The occurrence of HT-2 toxin and other trichothecenes in Norwegian cereals

A total of 449 grain samples, 102 barley, 169 wheat and 178 oat samples were collected from different regions of Norway from 1996–1998 crops, mainly from grain loads and silos. The samples were analysed for type A and B trichothecenes, the largest groups of mycotoxins produced by the Fusarium species, by gas chromatography with mass spectrometric detection (GC-MS). Factors affecting the presence of the different trichothecenes are discussed. Deoxynivalenol (DON) and HT-2 toxin were the trichothecenes most frequently detected, followed by T-2 toxin, nivalenol, and scirpentriol, scirpentriol being detected only in seven samples (>20 g/kg).Oats were the grain species most heavily contaminated with an incidence(% >20 g/kg) and mean concentration of positive samples of 70%(115 g/kg) for HT-2 toxin, 30% (60 g/kg) for T-2 toxin, 57%(104 g/kg) for DON, and 10% (56 g/kg) for nivalenol. The corresponding values for barley were 22% (73 g/kg), 5% (85 g/kg),17% (155 g/kg) and 6% (30 g/kg), and for wheat 1.2% (20 g/kg),0.6% (20 g/kg), 14% (53 g/kg) and 0% for HT-2, T-2, DON and nivalenol, respectively. Norwegian oats were found to contain HT-2 and T-2 toxin in concentrations that might be at threat to human health for high consumers of oats. The amount of DON was significantly lower than in the crop from previous years.This revised version was published online in October 2005 with corrections to the Cover Date.