A number of Fusarium fungi produce different mycotoxins in the trichothecene class including deoxynivalenol, nivalenol, T-2 toxin and HT-2 toxin, as well as some other chemically unrelated toxins, e.g., zearalenone and fumonisins. The Fusarium fungi commonly are found on cereals grown in the temperate and tropical regions of the Americas, Europe and Asia. Several of the toxin-producing Fusarium species can produce, to at least some degree, two or more of these toxins.
The European Scientific Committee for Food has adopted several scientific opinions on these toxins, evaluating deoxynivalenol in December 1999 (21) establishing a TDI of 1 ^g/kg bw, zearalenone in June 2000 (22) establishing a temporary TDI of 0.2 ^g/kg bw, fumonisins in October 2000 (23), updated in April 2003 (24), establishing a TDI of 2 ^g/kg bw, nivalenol in October 2000 (25) establishing a temporary TDI of 0.7 ^g/kg bw, T-2 and HT-2 toxins in May 2001 (26) establishing a combined temporary TDI of 60 ng/kg bw, and the trichothecenes as group in February 2002 (27).
In the framework of Directive 93/5/EEC the SCOOP-task "Collection of occurrence data on Fusarium toxins in food and assessment of dietary intake by the population of EU Member States" was performed and finalized in September 2003 (28). Based on the scientific opinions and the assessment of the dietary intake, maximum levels have been set (Table 4) for deoxynivalenol, zearalenone and fumonisins. With respect to fumonisins, analyses of grain from recent harvests indicate that maize and maize products can be very highly contaminated by fumonisins and measures should be taken to prevent highly contaminated maize and maize products from entering the food chain.
Intake estimates indicate that T-2 and HT-2 toxins can be of concern for public health. The development of a reliable and sensitive detection method, collection of more occurrence data and further investigation/research into the factors involved in determining the presence of T-2 and HT-2 toxins in cereals and cereal products, in particular in oats and oat products, is needed and of high priority.
It is not necessary, due to co-occurrence, to consider specific measures for 3-acetyl deoxynivalenol, 15-acetyl deoxynivalenol and fumonisin B3, as limits on deoxynivalenol and fumo-
nisins B1 and B2 also would protect the human population from unacceptable exposure to these three toxins. A similar argument applies to nivalenol, which to a certain degree co-occurs with deoxynivalenol. Furthermore, human exposure to nivalenol is estimated to be significantly below the temporary TDI. With respect to the other trichothecenes considered in the SCOOP-task, e.g., 3-acetyldeoxynivalenol, 15-acetyldeoxynivalenol, fusarenon-X, T2-triol, di-acetoxyscirpenol, neosolaniol, monoacetoxyscirpenol and verrucarol, the limited information available indicates that they do not occur widely and that the levels found generally are low.
Climatic conditions during plant growth, particularly at flowering, have a major influence on Fusarium toxin content. However, good agricultural practices, whereby risk factors are minimized, can prevent or reduce contamination by Fusarium fungi. Commission Recommendation 2006/583/EC of 17 August 2006 on the prevention and reduction of Fusarium toxins in cereals and cereal products (29) contains general principles for the prevention and reduction of Fusarium toxin contamination (zearalenone, fumonisins and trichothecenes) in cereals to be implemented by the development of national codes of practice based on these principles.
Maximum levels of Fusarium toxins are set for unprocessed cereals sold for first stage processing. Cleaning, sorting and drying procedures are not considered first-stage processing insofar as no physical action is exerted on the grain kernel itself. Scouring is considered first-stage processing. The degree to which Fusarium toxins in unprocessed cereals are removed by cleaning and processing may vary. Thus, to have enforceable legislation, maximum levels also have been set for final consumer cereal products and for major food ingredients derived from cereals. Maximum levels were established in 2005 for Fusa-rium toxins in cereals and cereal products, including maize and maize products. For maize, all of the factors involved in the formation of Fusarium toxins, particularly zearalenone and fumonisins B1 and B2, are not known precisely. The maximum levels in maize and maize products were implemented beginning 1 July 2007 for deoxynivalenol and zearalenone, and on 1 October 2007 for fumonisins B1 and B2.
Data for the 2005 and 2006 harvests indicate that higher levels of zearalenone and fumo-nisins, and to a lesser extent deoxynivalenol, were observed in European maize than in the 2003 and 2004 harvests. These differences appear to be linked to weather conditions. The maximum levels for zearalenone and fumonisins were exceeded for maize under some weather conditions, even when applying the recommended prevention measures to the greatest extent possible. Therefore, the maximum levels for deoxynivalenol, zearalenone and fumonisins Bj and B2 in maize and maize products were reevaluated to avoid disrupting the markets while still protecting the public's health. The Standing Committee on the Food Chain expressed on 20 July 2007 (30) a favorable opinion by unanimity on the modified maximum levels (Table 4). The Commission adopted on 28 September 2007 these measures by Commission Regulation (EC) No 1126/2007 as an amendment to Regulation (EC) 1881/2006.
Given the low contamination levels of Fusarium toxins found in rice, no maximum levels were set for rice or for rice products.
Discussions of possible maximum levels for T-2 and HT-2 toxins in cereals and cereal products were initiated in autumn of 2007 and should be finalized by 1 July 2008.
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