(1) the food crop that has been modified,

(2) the potential for any introduced DNA to encode harmful substances,

3) the safety of proteins encoded by Tran’s genes, and

(4) proof that known plant toxicants and important nutrients are within acceptable levels in the new variety.

There is some chance that proteins encoded by transgenes may cause allergies in some individuals; this is particularly so for proteins derived from such foods as milk, eggs, wheat, fish, tree nuts and legumes. There are some instances where a transgenic variety had to be withdrawn due to severe allergic reactions in some people, e.g., a soybean transgenic variety in Mexico.

4. Relevant toxicological data on the host organism.

Japan has decided to 'label' those GM foods that are found to be 'safe'.

Similarly, European Union has adopted legislation requiring mandatory labelling of all GM food. In contrast, U.S. Food and Drug Administration (FDA) requires the food to be labelled as genetically modified only if the changes introduced through genetic engineering have an impact on the safety or nutrition of the food itself.

Labelling is considered desirable because it gives the consumer the choice of deciding if he wishes to have GM food, but companies fear that labelling may frighten the consumers.