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[SANET-MG] gm crops for health? part 5



part 5
gm crops for health?

Yield or nutrition – a false dichotomy
The pressure to use genetics to boost crop yield, first with the green revolution, and then with genetic modification, may have resulted in a crisis in nutrition. Too many of the crops have become depleted in mineral nutrients, vitamins and essential building blocks [102], particularly as soils become depleted and exhausted. Healthy soils are needed for the production of healthy crops [59]. But maximising yield does not necessarily sacrifice nutrition if the land is properly managed for maximum internal organic input. This can be achieved by turning otherwise polluting livestock and crops wastes into food and energy resources [37], thereby mitigating climate change and solving the global energy crisis while providing food security for all. Genetic modification fails to address climate change and the depletion of energy, water, soil nutrients, and other agricultural resources that already threaten food security, and is a diversion of time and resources that the world can ill afford.

Comments for Codex Alimentarius

Foods enhanced in single nutrients do not constitute health foods and must be labelled Much effort is being devoted to improving the nutritional quality of crops intended for food through genetic modification to enhance production of single nutrients, minerals or vitamins. We question this approach as a whole. Nutrition depends on a balance of macro and micronutrients as well as cofactors and vitamins, which is best achieved by adopting organic agricultural practices. Furthermore, overdose of any single nutritional factor is likely to be toxic; and hence these genetically modified ‘health-enhancing’ food crops may well turn out to be serious public health hazards. Codex’s consultation document [103] states: “Working Group members recognized that safe upper intake levels should be determined for nutrients and related substances to prevent excessive intake by vulnerable populations. It was also recognized that there is a need to determine the safety of nutrients and related substances when upper limits have not been determined and to also consider the history of safe use of the nutrient when appropriate. However, it was also recognized that the issue was generic in nature.” It is already clear that many of the nutrients being genetically manipulated have upper limits of toxicity, particularly iron and selenium among minerals, vitamin A and possible vitamin E. It would be misleading and indeed dangerous to market foods enhanced in single nutritional factors as ‘health’ foods. And it is imperative to label such products clearly in order to avoid toxic overdose.

The safety of synthetic genes
Codex has not addressed the safety of synthetic genes that are being used, some of which produce proteins that are completely new to our food chain. Extreme examples are the synthetic storage protein genes to enhance amino acid content, and synthetic peptides for controlling pathogens. By definition, the products of synthetic genes are not “substantially equivalent” as they have no natural counterparts. Apart from the completely synthetic genes, many genes are synthetic approximations of natural genes or hybrid genes made of synthetic approximations of two or more genes. These too, constitute novel proteins in our food chain. All transgenic proteins should be comprehensively tested for toxicity and immunogenicity, bearing in mind that gene transfer even between closely related species involves changes in glycosylation patterns that may transform a normally harmless protein into a potent immunogen.

The safety of metabolic engineering
It is stated in the Codex consultation document [103] that, “foods derived from rDNA plants that have undergone modification to intentionally alter nutritional quality or functionality should be subjected to additional nutritional assessment - beyond that conducted when modifications are for other purposes - to assess the consequences of the changes and whether the nutrient intakes are likely to be altered by the introduction of such foods into the food supply.” Many of the genetic modifications involve massive alterations, such as the replacement of one or more metabolic pathways. Such changes increase the probability of creating unintended toxic by-products, and call for comprehensive comparisons of metabolic- transcriptional- and protein-profiles between GM varieties and the non-GM controls, as well as extensive safety trials.

RNA interference already shown to cause massive fatalities in mice
RNAi is being used increasingly to up or down regulate genes and pathways. The need for adequately testing such constructs is clear; the massive deaths of mice subjected to RNAi ‘gene therapy’ should serve as a warning. RNA interference is currently not included as genetic modification, and requires special attention.
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Safety tests should not be done on children in developing nations
The Codex consultation document [103] states: “…additional safety and nutritional considerations for the assessment of foods derived from rDNA plants modified for nutritional or health benefits include such aspects as bioavailability and physiological function of the intended modification. Particular focus will be given to staple crops of interest to populations in developing countries.” Safety and nutritional testing of all of the modifications described in the accompanying literature is clearly essential for all the areas of the world. But we emphasize that the initial testing of the modified crops should not be done on children of developing countries under the guise of providing medical care, as has been the case with GM rice producing proteins found in milk [104] (FDA in Third World Drug Trial Scandals), and those undertaking such unethical tests should be prosecuted.

GM probiotics should be banned
The genetic modification of probiotic bacteria should be banned until and unless extensive studies and safety tests have been carried out. These bacteria have co-evolved with their animal and human hosts for millions and billions of years, with an intricate network of relationships that is only just beginning to be understood, and if thrown out of balance, could result in serious disease. Genetically modifying these bacteria runs the risk of creating pathogens that are preadapted to invade the gastrointestinal tracts of their hosts, where horizontal gene transfer and recombination are rife.

The concept of “substantial equivalence” has no place in scientific risk assessment Finally, the concept “substantial equivalence” has no validity in risk assessment of GM food and food products, least of all in the area of metabolic engineering (see our comments for Genetically modified food animals [105] and should be rejected by Codex Alimentarius.

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