By Artemis Dona and Ioannis S. Arvanitoyannis
Critical Reviews in Food Science and Nutrition, 49:164-175 (2009)
As genetically modified (GM) foods are starting to intrude in our diet concerns have been expressed regarding GM food safety. These concerns as well as the limitations of the procedures followed in the evaluation of their safety are presented. Animal toxicity studies with certain GM foods have shown that they may toxically affect several organs and systems. The review of these studies should not be conducted separately for each GM food, but according to the effects exerted on certain organs it may help us create a better picture of the possible health effects on human beings. The results of most studies with GM foods indicate that they may cause some common toxic effects such as hepatic, pancreatic, renal, or reproductive effects and may alter the hematological, biochemical, and immunologic parameters. However, many years of research with animals and clinical trials are required for this assessment. The use of recombinant GH or its expression in animals should be re-examined since it has been shown that it increases IGF-1 which may promote cancer.
Introduction
Nearly fifteen years have passed after the introduction of genetic modifications (GM) in food and new GM food are added in the existing list of foods. Who could imagine that there would come a day when the pig would be as "fat -free healthy food" as a fish or that the ice cream our children eat would contain a protein from the fish? Are GM safe to human health? Studies concerning their safety are still few when one considers the toxicity studies that must accompany the application of any novel drug for approval by the corresponding drug administration. The results from most toxicity studies available in literature are reviewed and the significance of these findings is discussed. In the absence of adequate safety studies, the lack of evidence that GM food is unsafe cannot be interpreted as proof that it is safe. Furthermore, if they are not considered safe for human consumption why should they be approved for animals? Humans can inadvertently consume foods that contain GM products fed to animals, i.e., crops modified for enhanced productivity in animals. This was the case when traces of a StarLink GM crop, restricted for use only in feed, were found in taco shells already in the market. One has to wonder what will happen if we start consuming food crops contaminated with GM crops containing genes for the production of drugs and industrial chemicals that have never been assessed for their toxicity? (Margulis, 2006). The debate over its safety continues. One should not forget that every single GM food through the food chain will eventually reach the consumer. Issues such as the concern of the public for possible hazards due to the consumption of a GM food have already been discussed, but there is always something to add. However, prior to discussing these issues one must take into account in brief the regulation of testing for GM food safety.