‘Substantial Equivalence’ is an assessment concept created as an answer to the American system of ‘GRAS’.  While products of new technologies normally undergo rigorous testing procedures in the USA, the biotech industry there sought to market GM foods without subjecting them to regulatory delays and restrictions. The US government declined to set any statutory safety assessment of GM foods, until 2000, when it stipulated that biotech companies need to consult with the FDA (Food and Drug Administration) before marketing GM foods. (See U.S. Department of Health & Human Services, Press Release, May the 3^rd 2000: ‘FDA to Strengthen Pre-Market Review of Bioengineered Foods’.)  In 1992 the FDA produced a policy document which stated that GM foods should undergo the same pre-market safety testing as ‘food additives’. (See: Department of Health & Human Services, FDA, ‘Statement of Policy: Foods Derived From New Plant Varieties’, in Federal Register, Vol. 54 (1992), No. 104, pp. 22984-23001.) But under US law only NEW food additives needed to be tested – additives already in use were considered GRAS  (Generally Recognised As Safe). In effect, the FDA decided that GM foods were ‘nothing new’ because they ‘assumed’ that genetic modification could not introduce ‘unfamiliar substances’ into food, and that therefore GM foods could be ‘Generally Recognised As Safe’ (or GRAS).

‘Substantial Equivalence’ is a concept created by four international bodies as a compromise to the American GRAS evaluation. The World Health Organisation (WHO), the United Nations Food and Agriculture Organisation (FAO) the Organisation for Economic Cooperation and Development (OECD), and the International Food Biotechnology Council (IFBC) cooperated in an attempt to examine possible assessment systems for GM foods, but they encountered problems. It was recognised that standard procedures for testing the safety of single chemicals could not be applied to food (which is a complex mixture of different compounds) and admitted that few attempts to assess the safety of conventional foods (against which GM foods would be assessed) had been made. Scientists at the WHO and OECD concluded that adequate testing procedures for GM foods were not available, but given that America was marketing GM foods globally, the need to put some assessment procedure in place was critical.  They formulated a compromise called the concept of ‘Substantial Equivalence’.