«6th Fusarium-toxin Forum» Brussels, 9-10 February 2009 T-2 and HT-2 toxins in cereals in France Bruno BARRIER-GUILLOT INTERCEREALES COPA-COGECA b.barrier@arvalisinstitutduvegetal.fr 1 6th Fusarium-toxin forum
COPA-COGECA, INTERCEREALES COPA-COGECA: the voice of European farmers and co-ops since 1958 76 Member Organisations 15 million farmers 40.000 co-ops INTERCEREALES: professional organization of the cereal sector in France Production Collectors (coops, merchants) International trade First processing industries (food and feed) 2 6th Fusarium-toxin forum
Toxicity of T-2 & HT-2 Estimated dietary exposure Questions on T-2 & HT-2 and first answers Q1: levels found in cereals Q2: correlations with other Fusarium-toxins Q3/Q4/Q5: factors involved in formation of T-2 & HT-2 toxins / sources of variation / agricultural practices / possibilities to mitigate the risk Q8: screening and confirmatory methods of analysis + sampling 3 6th Fusarium-toxin forum
Toxicity of T-2 T 2 and HT-2 2 toxins From the group of trichothecenes A Produced by Fusarium langsethiae, a newly identified species from Sporotrichiella section. LOAEL = 0.029µg/kg-bw/d based on one experiment in pigs Safety factor = 10 x 10 x 5 due to less data available t-tdi = 0.06 µg/kg-bw/d SCF opinion, 30 May 2001 4 6th Fusarium-toxin forum
Toxicity of T-2 and HT-2 toxins «The toxicity of T-2 toxin in pigs in only one short-term study is used as the basis for the safety assessment Similar effects were not observed in other studies in pigs neither at this nor even at higer doses» «There are deficiencies on metabolism and toxicokinetic studies. To accound for this and the use of a LOAEL, an extra uncertainty factor of 5 was included, giving an overall uncertainty factor of 500» «The toxicity induced by T-2 & HT-2 toxin should be investigated» SCF Opinion, 30 may 2001 Necessity to have a recent, robust and scientific safety assessment on T-2 & HT-2 Less toxicity of HT-2 toxin vs T-2 toxin??? 5 6th Fusarium-toxin forum
Dietary exposure «For T-2 and HT-2 toxins, the estimated dietary intake exceed in most cases the t-tdi. However, most occurrence data are obtained by making use of methods of analysis with high limit of detection The dietary intake is strongly influenced by the limit of detection of the used analytical methods» 856/2005 and 1881/2006 Regulations Problems with scoop task 3.2.10 report (2003) Probably over-estimation of calculated exposure to T-2 & HT-2 toxins The lower the LoD, the lower the calculated exposure! Necessity to have a recent dietary exposure study with low LoD 6 6th Fusarium-toxin forum
2006-2010: Second French Total Diet Study (TDS) Aim: to get an accurate and realistic view of exposure to contaminants for the purposes of quantitative risk assessment Method: Study based on a standardized methodology recommended by WHO; 20,280 different food products purchased in 2007-2008, making up 1,352 composite samples of core foods to be analyzed Analysis: several contaminants including mycotoxins, Exposure of the population assessed by crossing Contamination data and consumption data from the INCA2 national survey (2006-2007) Results: 2009-2010 AFSSA 7 6th Fusarium-toxin forum
Q1: Occurrence found in cereals Wheat and durum wheat seem to accumulate low T-2 and HT-2 toxins, but sporadic high levels can occur T-2 and HT-2 toxins levels in maize are uncertain (2006: an exceptional climate?) Spring barley and oats are more susceptible and must be carefully examined 8 6th Fusarium-toxin forum
T-2 2 and HT-2 2 in maize 100% 96% 2006: an exceptional year? 80% 60% 2006 2007 40% 30% 23% 24% 20% 0% 1% 0% 11% 1% 6% 0% 3% 1% 1% 0% 3% 0% <10 10-50 25-50 50-75 75-100 100-150 150-200 >200 Arvalis-ONIGC (2006 and 2007 surveys) T2+HT2 µg/kg 9 6th Fusarium-toxin forum
T-2 2 and HT-2 2 toxins in barley 60 50 Average (µg/kg) 40 30 20 10 0 Winter barley Spring barley Arvalis (field surveys, 2006 and 2007) 10 6th Fusarium-toxin forum
T-2 2 and HT-2 2 toxins in spring barley 60% 40% 39% 39% 2006 n=28 2007 n=120 2008 n=292 27% 27% 23% 26% 29% 22% 20% 18% 0% 9% 8% 6% 4% 4% 4% 2% 4% 3% 4% 1% 3% 0% 0% 0% <10 10-25 25-50 50-75 75-100 100-150 150-200 >200 Arvalis (field surveys, 2006,2007,2008) T2+HT2 µg/kg 11 6th Fusarium-toxin forum
T-2 2 and HT-2 2 toxins in oats 100% 80% 60% A great variability of levels 40% 20% 18% 21% 12% 12% 18% 18% 0% <10 10-50 25-50 50-75 75-100 100-150 150-200 >200 Arvalis (field surveys, 2008) 0% 3% T2+HT2 µg/kg 12 6th Fusarium-toxin forum
Relationship between T-2 T 2 and HT-2 2 toxins in cereals 2.5 times more HT-2 toxin than T-2 toxin T2 µg/kg 140 120 100 80 60 40 20 Wheat Durum Wheat Winter Barley Spring Barley 0 0 50 100 150 200 250 300 HT2 µg/kg Arvalis (field surveys, 2006 and 2007) 13 6th Fusarium-toxin forum
Q2: Correlation with other Fusarium-toxins T2+HT2 µg/kg 300 250 200 150 100 50 Exclusion between T-2 T & HT-2 2 and DON contents in cereals Wheat Durum Wheat Winter Barley Spring Barley 0 0 1000 2000 3000 DON µg/kg Arvalis (wheat and barley field surveys) 14 6th Fusarium-toxin forum
Experimental confirmation on durum wheat 150 140 130 T2+HT2 µg/kg 120 110 100 90 Control Effective fight against F. graminearum 80 70 60 0 100 200 300 400 500 600 700 800 900 DON µg/kg Fungicide trial on durum wheat, Léméré Arvalis 2008 (CT durum wheat Centre-Ile de France) 15 6th Fusarium-toxin forum
Why an apparent opposition between T-2 & HT-2 2 toxin and DON levels? Competition between different Fusarium species? Different optimal conditions of growth for the different species of Fusarium producing T-2 & HT-2 or DON? Spore release (and head blight contamination) later for species producing T-2 & HT-2 (than for DON), and more in phase with the period of susceptibility to infection of spring barleys? 16 6th Fusarium-toxin forum
Q3/Q4/Q5 Factors involved? Agricultural practices? A network of field surveys in France undertaken by Arvalis since 2006 on spring barleys Characterize the Fusarium-toxin contents (DON, T2 & HT2) of barley in collaboration with agrosupply distributors (coops and merchants) Analyse the situation of each region Identify involved factors, weigh the importance of these factors and study their interactions Improve knowledge, identify the actions of prevention and disseminate good practices 17 6th Fusarium-toxin forum
DON contamination in wheat is plurifactorial Climate**** Harvest residues*** Cultivar** Fungicides* Clean crop Previous crop Tillage Storage End-uses sowing flowering harvest Factors : from the highest (****) to the lowest (*) of importance ARVALIS-Institut Institut du végétal, v 2005 18 6th Fusarium-toxin forum
T-2 & HT-2 2 contents in spring barley according to previous crop Median µg/kg 50 45 40 35 30 25 20 15 10 5 0 Difference with DON! Small grain cereals as a previous crop lead to higher T-2 & HT-2 contents in following spring barley T2+HT2 Median µg/kg 168 147 126 105 Barley Wheat Maize Beet Other 84 63 42 21 0 DON Barley Wheat Maize Beet Other n=292 Arvalis (Field survey, 2008) 19 6th Fusarium-toxin forum
T-2 & HT-2 2 contents in spring barley according to previous crops T-2 and HT-2 contents increase with the number of small grain cereals during the two previous years 50 Median µg/kg 40 30 20 10 n=292 0 0 1 (2 year previous) Arvalis (Field survey, 2008) 1 (1 year previous) 2 Nb of small grain cereals 20 6th Fusarium-toxin forum
Experimental confirmation in wheat T-2 & HT-2 2 contents according to previous crop 50 5 plots T-2/HT-2 µg/kg 40 30 20 10 5 plots 0 Maize Wheat Arvalis (Boigneville tillage system trial, 2008) 21 6th Fusarium-toxin forum
T-2 & HT-2 2 contents in spring barley according to date of sowing The later the date of sowing the higher the T-2 and HT-2 toxin levels T2+HT2 µg/kg 50 40 30 20 10 Median Mean n=292 0 october november januaryfebruary Arvalis (Field survey, 2008) marchapril 22 6th Fusarium-toxin forum
T-2 & HT-2 2 contents in spring barley according to date of sowing 2 times less T-2 & HT-2 toxin levels with automn sowing T2+HT2 µg/kg 50 40 30 20 10 Median Mean 0 Automn Arvalis 2008 (Ouzouer trial) February 6 cultivars x 2 dates of sowing 23 6th Fusarium-toxin forum
What about cultivar and fungicide effects? Problem : inability to inoculate cereals with F. Langsethiae producing T-2 and HT-2 toxins to mimic natural infection! Necessity of improving knowledge On the biology of the Fusarium langsethiae On competition between the different Fusarium (TCT B vs TCT A producers) Only after it will be possible to evaluate the cultivar susceptibility to accumulate T-2 & HT-2 and the fungicide effect 24 6th Fusarium-toxin forum
Q3/Q4/Q5 Factors involved? Agricultural practices? What is known about DON prevention seems to be not applicable for T-2 & HT-2 toxins Commission recommendation on 17 august 2006 (2006/583/EC) on the prevention and reduction of Fusarium toxins in cereals is not suitabled for T-2 and HT-2 toxins 25 6th Fusarium-toxin forum
Q8: Screening and confirmatory methods of analysis Reference analyses Complex analysis, very expensive equipment, expensive analyses Question of LoD Not appropriate for the screening of batches Developed methods : LC/MS/MS GC/MS HPLC/Fluorescence Improvement of analytical methods for the determination of T-2 and HT-2 by LC/MS/MS on cereals Aims : Project managers : IRTAC / Arvalis / Capinov Partners : 10 laboratories Beginning of the study : February / March 2009 (for 30 months) Studies and improvement of critical points Ring Test Project of a method for European normalization 26 6th Fusarium-toxin forum
Q8: Screening and confirmatory methods of analysis Rapid detection methods Necessity to have rapid, accurate and cheap methods for a first screening of batches Focus on ELISA Test KITS : ELISA test kits for T-2 are available They must be evaluated (cross-reaction between T-2 and HT-2 toxins?) ELISA test kits for HT-2? Focus on lateral flow devices : The first tests for T-2 / HT-2 toxins have just been available They must be evaluated 27 6th Fusarium-toxin forum
A research program 2008-2010: 2010: BARSAFE Fusarium langsethiae, from barley culture to the finished products (beer) and by-products: study of The biology and the epidemiology of the pathogen, The conditions of T-2 & HT-2 toxins production, Their transfer, biological breakdown and toxicity, for a better sanitary risk management Partners: IFBM (coordinator), ARVALIS, INRA, CNRS-INPL-ENSAIA with funding of French Research National Agency 28 6th Fusarium-toxin forum
Toxicity assessment Occurrence in cereals Biology of F. langsethiae Inoculation trial Conclusion : a lack of knowledge at all stages Dietary exposure (with updated LoD) Cultivar, fungicide evaluation Identification of agronomic factors Risk assessment matrix Agro-climatic models Sampling method Chromatographic method of analysis Normalized method of analysis Screening method of analysis Situation for T-2 &HT-2 One study Not available 3 years available Not available Not available Not available 1st results Not available Not available No data Available but expensive Not available Not available?? DON - 29 6th Fusarium-toxin forum
Thank you for your attention 30 6th Fusarium-toxin forum