products may be assessed in the same way as conventionally bred products. Further, the relative precision of biotech methods should allow assessment to be focused on the most likely problem areas. The concept of substantial equivalence is then described as a comparison between a GM food and a similar conventional food, taking into account food processing, and how the food is normally consumed, including quantity, dietary patterns, and the characteristics of the consumer population. Assessment process Substantial equivalence is the starting point for GM food safety assessment. It can be applied at different points in the food chain, from unprocessed harvested crop to final ingredient or product, depending on the nature of the product and its intended use. For a GM plant, the overall evaluation process may be viewed in four phases: Substantial equivalence analysisConsidering introduced genes, newly expressed proteins, and new secondary metabolites Toxicological and nutritional analysis of detected differencesGene transfer, allergenicity, degradation characteristics, bioavailability, toxicity, and estimated intake levels Toxicological and nutritional evaluationIf necessary, additional toxicity testing, possibly including whole foods (return to Phase 2). Final safety assessment of GM plant Technological developments There has been discussion about applying new biochemical concepts and methods in evaluating substantial equivalence, such as metabolic profiling and protein profiling. These concepts refer, respectively, to the complete measured biochemical spectrum (total fingerprint) of compounds (metabolites) or of proteins present in a food or crop. The goal would be to compare overall the biochemical profile of a new food to an existing food to see if the new food's profile falls within the range of natural variation already exhibited by the profile of existing foods or crops. However, these techniques are not considered sufficiently evaluated, and standards have not yet been developed, to apply them. Adoption Approaches to GM food regulation vary by country, while substantial equivalence is generally the underlying principle of GM food safety assessment. This is the case for national and international agencies that include the Canadian Food Inspection Agency (CFIA), Japan's Ministry of Health, Labour and Welfare (MHLW), the US Food and Drug Administration (FDA), and the United Nations' Food and Agriculture Organization (FAO) and World Health Organization. In 1997, the European Union established a novel food assessment procedure whereby, once the producer has confirmed substantial equivalence with an existing food, government notification, with accompanying scientific evidence, is the only requirement for commercial release, however, foods containing genetically modified organisms