|
|
|
|
|
|
Funding institutions:
financed from own resources
Project manager:
Dr. Susanne Stirn
Duration:
continuously
The safety assessment of genetically modified foods is performed according to the concept of substantial equivalence, developed by the OECD in 1993. The basis of this concept is to compare the genetically modified plant or food with its conventional counterpart which is considered to be safe for human consumption. The safety assessment focuses on the determined differences. More precisely, the substantial equivalence is established by comparing the macro- and micronutrients as well as known toxicants and allergens. The OECD provides consensus documents on the compositional considerations for different crop plants. PDF
Most of the genetically modified plants commercialized today contain only one or a few genes mainly conferring herbicide- and/or insect resistance. They have been found to be substantially equivalent to their conventional counterpart except for the newly introduced protein(s). These have been assessed for their toxic and allergenic potential and if no risks for humans have been identified placing on the market was granted.
In the beginning, the discussion of the safety assessment focused on the question whether the concept of substantial equivalence is at all suitable for genetically modified food. Since it became the basis of approval of gm plants worldwide and no disaster with gm food became apparent, objections were raised against the high hurdle for gm plants in contrast to conventional varieties. Using potatoes as a case study, we analysed the different ways of regulatory handling of potential health risks and looked at reported incidents of negative health effects. In summary, we concluded that the regulatory burden for genetically modified crop plants is adequate since the new possibility in plant breeding to transfer genes between unrelated species is accompanied by new risks, especially in the case of potential allergens (Stirn and Beusmann, 2003). Except for Canada where plants produced with the help of mutagenesis are regulated similarly, the different regulatory treatment of genetically modified and conventionally bred plants is implemented worldwide.
Later on, the discussions around the safety assessment focused on single test systems to establish food safety: It was criticised that for regulatory approval only the isolated, newly expressed protein was used in toxicity tests instead of the whole genetically modified food. In the case of allergenic potential no predicative test exists and the safety assessment relies on the sum of test results covering single aspects of allergen characteristics. Further development of test systems was demanded (Stirn, 2007).
In the future, genetically modified plants will be commercialized with modified metabolic pathways to benefit human health (e.g. enhanced vitamin content, reduced allergen concentrations). It is expected that for these so-called “functional foods” it will become more difficult to establish food safety. To identify the gm plants with additional consumer benefits which are expected to be commercialized soon we first reviewed the scientific literature. Several traits have been described, ranging from expression of beneficial fatty acids to the enhancement of micronutrients and the elimination of allergens (Stirn and Lörz, 2006).
For a long period of time these gm plants have been and still are announced to be “just around the corner”. We analysed the regulatory status of gm plants with additional consumer benefits in the USA and the EU (field trials, applications for commercialisation) and the gm plants being in the R&D-pipeline of the life science industries. Currently, only a few applications for commercialisation have been submitted in Europe as well as in the USA (Stirn, 2006). () We are looking at the safety assessment of selected gm plants with additional consumer benefits as case studies to identify potential gaps in the safety assessment according to the concept of substantial equivalence. Depending on the respective gm plant, open questions remain:
References:
STIRN, SUSANNE (2007): Grundsätze der Abschätzung möglicher gesundheitlicher Wirkungen gentechnisch veränderter Organismen, Gutachten für die interdisziplinäre Arbeitsgruppe Gentechnologiebericht der Berlin-Brandenburgischen Akademie der Wissenschaften. PDF (German only). Expertise for the “Second Gene Technology Report” of the Berlin-Brandenburg Academy of Sciences and Humanities PDF
STIRN, SUSANNE (2006): Gentechnisch veränderte Pflanzen mit zusätzlichem Verbrauchernutzen - Warum ist eine Vermarktung weiterhin nicht in Sicht? BIOGUM-Forschungsbericht/BIOGUM-Research Paper, FG Landwirtschaft, Nr. 15, Hamburg, ISBN3-937792-19-8. PDF
STIRN, SUSANNE AND HORST LÖRZ (2006): Transgenic Plants for Food Use. In: Robert. A. Meyers (ed.) Genomics and Genetics: From Molecular Details to Analysis and Techniques. Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim ISBN: 978-3-527-31609-0, S. 905-937. table of content
STIRN, SUSANNE AND VOLKER BEUSMANN (2003): Vergleich der Sicherheitsabschätzung gentechnisch veränderter und konventionell gezüchteter Lebensmittel am Beispiel der Kartoffel. Deutsche Lebensmittel-Rundschau 10, 395-403. PDF
