Genetically engineered foods are not safe, have not been properly tested and pose a serious threat to human health and the environment, according to a new report by two genetic engineers.

In GMO Myths and Truths, the scientists refute the claims made by companies that produce genetically modified crops and organisms (GMOs).

"GM crops are promoted on the basis of ambitious claims - that they are safe to eat, environmentally beneficial, increase yields, reduce reliance on pesticides and can help solve world hunger,"
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But the research on them is incomplete, lack proper testing in humans or any long-term study, the report said. Regulatory agencies all over the world typically rely on information supplied by the for-profit companies producing GMO products, rather than any independent testing.

Furthermore, the authors said, GMO crops have increased the use of toxic herbicides and pesticides that have been linked to cancer, birth defects and other medical issues.

In the debate over genetically modified food, it often seems that one side is painted as pro-science (the GMO advocates), while the other side is portrayed as being scared of beneficial technology that could help us all.

The report might seem like just another anti-GMO screed--until you see that it’s written by genetic engineers.

What are these scientists worried about?

• Genetic engineering is not, as proponents claim, an extension of natural plant breeding. While natural breeding takes place only between related kinds of life, genetic engineering happens in a lab, where tissue cultured plant cells undergo a GM gene insertion process that couldn’t happen in nature. This is not in and of itself a bad thing.
• One of the problems, say the researchers, is that genetic engineering is imprecise and the results are unpredictable, with mutations changing the nutritional content of food, crop performance, and toxic effects, among other things. Every generation of GMO crops interacts with more organisms, creating more opportunities for unwanted side effects.
• GMO technology is becoming more precise, but the authors contend that accidents will always happen and, in any case, plant biotechnologists don’t really know much at all about crop genomes--so inserting genes at a supposedly safe area could still lead to all sorts of side effects.
• GMO crops can be toxic in three ways: The genetically modified gene itself (i.e. Bt toxin in insecticidal crops); mutagenic or gene regulatory effects created by the GMO transformation process; and toxic residues created by farming practices (i.e. from the Roundup herbicide used on GMO Roundup Ready crops).
• GMO food regulation varies widely by country. In the U.S., the FDA doesn’t have a required GMO food safety assessment process--just a voluntary program for review of GMO foods before they go on the market (not all commercialized GMO food crops have done this).
• Independent GMO crop risk research is hard to come by because, as the report explains, "independent research on GM crop risks is not supported financially--and because industry uses its patent-based control of GM crops to restrict independent research. Research that has been suppressed includes assessments of health and environmental safety and agronomic performance of GM crops." A 2010 licensing agreement between Monsanto and USDA scientists should make it easier to conduct research--but the report explains that it’s still restrictive.