Inadequate safety assessment of GE foods

It is a scientifically well recognized fact that genetic engineering can cause the appearance of unexpected very harmful substances. Therefore a very careful procedure is necessary for establishing the safety of GE foods. However this is not the case.

In stead of careful testing, a procedure has been used that may let through harmful GE foods.

The only requirement for approval is that the GE food should be grossly similar to its natural counterpart. This is called the principle of "substantial equivalence" (SE). However, a GE food may not only be grossly similar, but almost completely identical with its natural counterpart and yet contain an unexpected and undiscovered harmful substance.

Consequently, foods approved on the basis of "substantial equivalence" are not safe to eat.

This includes all GE foods on the market in the world. They have all been approved on the basis of "substantial equivalence".

Therefore, it is our conclusion that every GE-food must be withdrawn from the market.


Scientifically invalid

The the principle of "substantial equivalence" for GE food approval is unscientific, being based on incorrect assumptions about the effects of genetic engineering.

The assumption is that if it is established that the genetically engineered organism is similar to its natural counterpart, "substantially equivalent", then there is no reason to believe that it is hazardous.

To decide if a GE food is substantially equivalent, only a limited set of characteristics (selected by the manufacturer) needs to be compared according to this principle. If this superficial testing procedure reveals no significant difference between the GE food and its natural counterpart, then no further food safety testing is required.

So it is assumed that GE foods are safe if they are "substantially equivalent". This assumption would have been valid only if genetic engineering had been a safe technology that never could give rise to unexpected substances. However the opposite is the case:

Molecular biological theory as well as experimental findings indicate that unexpected substances may be created in GE foods. This includes carcinogenic (cancer-generating), mutagenic (mutation-generating), poisonous and allergenic substances, see "Genetic Engineering Possesses Inherent Unpredictability" [EL] and "The safety of GE foods. Reasons to expect hazards and the risk for their appearance". [ML]  [Partly EL]. This is especially problematic as it may be very difficult to detect such hazardous substances. Some poisons are harmful even in very small concentrations.

Unexpected substances may appear however "equivalent" the GE variety is. This means that a GE food may be hazardous even if it is not just substantially equivalent but completely equivalent with the natural counterpart but for one unexpected harmful substance that runs a considerable risk of being undiscovered unless very rigorous food safety testing is done. This was the case in the Showa Denko disaster, see the box below.

Examples of failure of the present approval procedure

  • A dreadful example demonstrating that approval based on "substantial equivalence" is not only useless but also dangerous is the "Showa Denko" tryptophan disaster that killed 37 and permanently disabled 1.500 persons, see "An example of fatal substantial equivalence".

  • Recently, an analysis of Professor Gilles-Eric Seralini on research regarding the effects of GE Maize on mice pointed out that there were 67 significant changes which could indicate toxicity. The Maize was approved as human food on the basis of substantial equivalence. More.

  • Liver, pancreas and testicular changes were detected in mice eating genetically engineered RoundupReady soy of Monsanto, declared "substantially equivalent" and therefore approved as human food. It is widely used. See "Liver changes from GE food".

The approval procedure has been rejected by important bodies of scientists

During year 2000 critisism and rejections of the approval procedure based on "substantial equivalence" began to be expressed by important bodies of scientists. This includes a/o the US National Academy of Science; its Canadian counterpart, the Royal society and the The UK Medical Research Council. It has also recently been revealed that the US Food and Drug Administation (FDA), suppressed serious concerns about the safety of GE foods expressed by its own experts. Below just one example:

The Royal Society of Canada:
SE is not a scientific safety standard

"...substantial equivalence does not function as a scientific basis for the application of a safety standard, but rather as a decision procedure for facilitating the passage of new products, GE and non-GE, through the regulatory process, " -

The Royal Society of Canada (see footnote) (2001) Elements of Precaution: Recommendations for the Regulation of Food Biotechnology in Canada, Ottawa, p.182 (April 2001).


Footnote: In British Commonwealth countries, the Royal society is a national body of distinguished scientists and scholars that promote learning and research. In other countries, the corresponding body is called "The National Academy of Science".

The rejection of Substantial Equivalence by these distinguished bodies of scientists becomes even more understandable if you study the table below that demonstrates important differences between the procedure based on substantial equivalence and rigorous scientific assessment.

We have been critisizing this approval procedure since several years and feel greatly satisfied to find that important bodies of scientists now have joined us in rejecting it. It should now be a matter of short time before the GE food approval regulations will be changed accordingly. This should inevitably lead to the withdrawal of all GE foods on the market as they were all approved on the basis of this flawed principle.

For more about the criticism by scientific bodies, see "Scientists and scientist organizations rejecting the principle of Substantial Equivalence".


See also

  • "Our recommendation" [EL] (in the end of this document) - Presently marketed GE foods should be withdrawn from the market as they have not been tested properly. New regulatory procedures for establishing food safety need to be established that effectively prevent political interventions and exclude the influence from biased scientists and industrial lobbyists.
  • The approval of Monsanto's genetically engineered Roundup Ready Soy as a food. [ML]
    A case illustrating the inadequacy of the principle of Substantial Equivalence as appliced in practice.

Table comparing substantial equivalence with a scientifically valid food assessment procedure

Safety assessment based on substantial equivalence as applied in practice (on the basis of the recommendations of the United Nation's organ FAO), is compared below with the kind of assessment required from a rigorously scientific and impartial standpoint.

 Assessment based on
substantial equivalence

 Assessment based on
scientific knowledge

Based on the unsubstantiated assumption that genetic engineering is not different from breeding. If there is no obvious difference between the assessed product and it's natural counterpart, regarding its appearance, taste, or selected chemical and nutritional properties, it is assumed to be equivalent and then no thorough testing is necessary.

Based on the scientific fact that there is a considerable difference between GE and breeding. Because of the insertion of a foreign gene, unpredictable metabolic changes may occur that may generate unexpected hazardous substances that require thorough testing to be detected.

Food that is substantially equivalent with regard to selected characteristics need only be tested as follows:

No food can be excluded from rigorous testing on the basis of comparing selected characteristics or for any other excuse. The GE organism may be identical with its mutual counterpart but for one harmful substance. Therefore the following tests are always necessary:

1. Short term animal testing with assessment of the influence on growth rate and similar gross and superficial symptoms (not even this is explicitly required)

1. Short term animal testing with thorough laboratory analysis of the effects on the condition of the animal. For detection of immediate harmful effects.

2. No long term animal testing at all is required

2. Rigorous long term animal testing is necessary for detection of slow acting harmful substances

3. No human testing at all is required

3. Rigorous human testing over long periods of time, that is years is necessary, as animal testing is not a fully reliable means for detecting harmfulness to humans

 4. Biochemical allergen analysis is accepted for assessing allergenicity

 4. Human allergy testing, both short and long-term, is necessary for reliable assessment of allergenicity. Biochemical analyses are not reliable indicators of allergenicity, neither are animal tests.


For more details about scientifcally required testing, see the right table column in: The approval of Monsanto's genetically engineered Roundup Ready Soy as a food. [ML]


Conclusions from the comparison above

It is obvious from this table that GE food "safety assessment" based on substantial equivalence has no scientific basis. This principle neglects well established scientific facts of crucial importance for food safety assessment. These facts invalidate the principle completely. Its application carries with it a great risk that unexpected harmful substances will pass undetected. Foods assessed this way are consequently not safe to eat. This goes for all GE foods on the market as they have all been approved on the basis of this principle.


Why did this unreliable assessment method appear?

To be reliable, the testing demanded by food safety experts would have cost millions of dollar in each case. In addition, it would have delayed their approval for years as such testing takes long time. Billions of dollars had already been invested in the development GE foods and such demands and delays would have made the GE food projects unprofitable. So the Biothec firms were under pressure to find some way to get around these impediments.

The solution was "substantial equivalence" that was invented by legal advisors to facilitate rapid approval procedures for GE foods in USA without any demands on careful testing. It is thus a judicial non-scientific hoax. Unfortunately it was succesfully established globally. This was achieved through strong pressure from the United States Government that made it a national and even a presidential issue to promote its Biotech Multinationals so that they could lead and dominate the biotech sector. US FDA played a key role in officially declaring (1994) that these foods were as safe as natural ones (this they did in spite of warnings by their own experts, who however were silenced, see FDA scientists indirectly rejected the principle).

The European Union initially did not accept the foods on these premises, but then the US government threatened with trade war if the foods were not approved.

What we find especially inquieting is that the scientific experts of international and national food safety committees supported this approval procedure. This made it possible to get it accepted as an internationally established norm. Their approval of a non-scientific assessment method represent an unacceptable failure of the procedures for developing food safety regulations and indicates a serious dysfunction of the national and international scientific expert committees that endorsed it (most of these decisions were about 1994-1997).

This shows the danger of political and corporate intervention into judgements and decisions that should be made completely impartially by independent scientists. See also "Towards a pseudoscientfic world order?"

For more details, see "Why were genetically engineered foods approved in spite of insuffient safety data?"


Our recommendation

We recommend that foods that have been approved on the basis of the principle of Substantial Equivalence should be declared unsafe and be withdrawn from the market, see our Open letter to governments. If it takes time to implement this, mandatory labeling is necessary for all GE foods and food containing GE components in order to facilitate early discovery of unexpected harmful effects.

Regulations for securing the safety of food should only be based on impartial scientific considerations. This has obviously not been the case in regulations applying the principle of substantial equivalence.

Measures need to be introduced in the regulatory procedures that prevent political interventions and exclude the influence from biased scientists and industrial lobbyists (see: A suggested procedure to ensure impartial safety assessment). Without drastic improvements of the regulatory procedures, the health of the population of the Earth may be exposed to peril from insufficiently tested Novel foods that now are being developed and marketed.

Physicians and Scientists for Responsible Application
of Science and Technology


Published at Nov 3, 1998. Last updated Aug 3, 2006.


Scientists and scientist organizations rejecting the principle of Substantial Equivalence

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