Since the first commercial growing began in 1996, the global area of genetically modified (GM) crops is reported to have increased 100-fold. However, nearly 90 % are confined to 5 countries, with top grower the US accounting for more than 40 %. GM crops have been largely excluded from Europe and most developing countries because opposition has been growing simultaneously as widespread agronomical failures of the GM crops as well the health and environmental impacts are coming to light.
GM remains limited to three major crops – soybean, maize and cotton – and two traits: herbicide (mainly glyphosate) tolerance (HT) at nearly 60 % and insect resistance with toxins from the soil bacterium Bacillus thuringiensis (Bt) at 15 %, with the remaining stacked traits (HT and one or more Bt) at 25%.
The failures and hazards of glyphosate and glyphosate tolerant crops and Bt crops are reviewed respectively in Chapter 1 and Chapter 2. Chapter 3 reviews the range of hazards resulting from the uncontrollable, unpredictable process of genetic modification itself in the light of advances in molecular genetics within the past decade, which tells us why the technology cannot be safety applied to grow our crops or produce our food.
Glyphosate and glyphosate tolerant crops
Glyphosate use has gone up sharply worldwide since the introduction of glyphosate-tolerant GM crops. Herbicide use per acre has doubled in the US within the past five years compared with the first five years of commercial GM crops cultivation, the increase almost entirely due to glyphosate herbicides. Glyphosate has contaminated land, water, air, and our food supply. Damning evidence of its serious harm to health and the environment has been piling up, but the maximum permitted levels are set to rise by 100-150 times in the European Union with further hikes of already unacceptably high levels in the US if Monsanto gets its way.
- Scientific evidence accumulated over three decades documents miscarriages, birth defects, carcinogenesis, endocrine disruption, DNA damage, general toxicity to cells, neurotoxicity, and toxicity to liver and kidney at glyphosate levels well below recommended agricultural use.
- The major adjuvant POEA in glyphosate Roundup formulations is by far the most cytotoxic for human cells, ahead of glyphosate and its metabolite. It also amplifies the toxic effects of glyphosate.
- A recent review blames glyphosate for practically all modern diseases as its general chelating action affects numerous biological functions that require metal cofactors. It is the most pervasive environmental chemical pollutant that also inhibits enzymes involved in detoxification of xenobiotics, thereby increasing their toxicity. In addition, it kills beneficial gut bacteria that prevent pathogens from colonizing the gut and promotes the growth of the pathogenic bacteria, leading to autism and other diseases.
- Rats fed Roundup contaminated and Roundup tolerant maize beyond the required 90 days showed a startling range of health impacts. Females were 2 to 3 times as likely to die as controls and much more likely to develop mammary tumours. In males, liver congestions and necrosis were 2.5 to 5.5 times as frequent as controls, while kidney diseases were 1.3-2.3 times controls. Males also develop kidney or skin tumours 4 times as often as the controls and up to 600 days earlier. The harmful effects were found in animals fed the GM maize that was not sprayed with Roundup, as well as those that were, indicating that the GM maize has its own toxicities apart from the herbicide.
- Livestock illnesses from glyphosate tolerant GM feed including reproductive problems, diarrhoea, bloating, spontaneous abortions, reduced live births, inflamed digestive systems and nutrient deficiencies. Evidence has also emerged of chronic botulism in cattle and farmers as the result of glyphosate use.
- Glyphosate is lethal to frogs and Roundup is worse; it increases toxic blooms, and accelerates the deterioration of water quality. It use also coincides with the demise of monarch butterflies.
- Glyphosate poisons crops and soils by killing beneficial microorganisms and encouraging pathogens to flourish. Forty crop diseases are now linked to glyphosate use and the number is increasing.
- Glyphosate-resistant weeds cover 120 million ha globally (61.8 m acres in the US) and continue to spread; it is a major factor accounting for the enormous increase in pesticide use since herbicide tolerant GM crops were introduced.
- Contamination of ground water supplies, rain, and air has been documented in Spain and the US. Berlin city residents were found to have glyphosate concentrations above permitted EU drinking water levels.
Bt crops were sold on the premise that they would increase yields and reduce pesticide use; instead they have resulted in too many crop failures, and the introduction of Bt cotton is now acknowledged to be responsible for the escalation in farm suicides in India.
- Bt crops’ claim to reduce pesticide use is based on excluding the Bt produced in the crops in total ‘pesticides applied’; but the Bt toxins leach from the plants and persist in soil and water, with negative impacts on health and the ecosystem comparable to conventional pesticides.
- Fungicide use and insecticide treatment of corn and soybean have gone up dramatically since the introduction of Bt crops.
- The breakdown of Bt traits due to target pest resistance and secondary pests has resulted in increasing use of conventional pesticides; and pesticide companies are reporting 5 to 50% increase in sales for 2012 and the first quarter of 2013.
- Contrary to industry’s claim that Bt is harmless to non-target species, independent studies showed that Bt toxins elicit immune response in mammals in some cases comparable to that due to cholera toxin. This is consistent with farm workers’ reports of allergic symptoms affecting the eyes, skin and respiratory tract.
- A new study found Bt proteins toxic to developing red blood cells as well as bone marrow cells in mice.
- Toxicity to human kidney cells has been observed in vitro, consistent with in vivo experiments in lab animals showing toxicity to heart, kidney and liver.
- Bt crops fail to control target pests due to insufficient expression of Bt toxins, thereby promoting the evolution of resistance.
- Bt crops promote the emergence of secondary pests when target pests are killed. Primary and secondary pests are already huge problems in the US, India and China, and are now hitting multiple crops in Brazil since Bt maize was introduced.
- Stacked varieties containing multiple Bt toxins are predicted to hasten the evolution of multiple toxin resistance, as resistance to one toxin appears to accelerate the acquisition of resistance to further toxins.
- Bt toxins harm non-target species including water fleas, lacewings, monarch butterflies, peacock butterflies and bees, which are showing worrying signs of population decline across the world.
- Bt toxins leach into the soil via the root of Bt crops where they can persist for 180 days; this has been linked to the emergence of new plant diseases and reduced crop yields.
- Bt toxins also persist in aquatic environments, contaminating streams and water columns and harming important aquatic organisms such as the caddisfly.
New genetics and hazards of genetic modification
The rationale and impetus for genetic engineering and genetic modification was the ‘central dogma’ of molecular biology that assumed DNA carries all the instructions for making an organism. This is contrary to the reality of the fluid and responsive genome that already has come to light since the early 1980s. Instead of linear causal chains leading from DNA to RNA to protein and downstream biological functions, complex feed-forward and feed-back cycles interconnect organism and environment at all levels, marking and changing RNA and DNA down the generations. In order to survive, the organism needs to engage in natural genetic modification in real time, an exquisitely precise molecular dance of life with RNA and DNA responding to and participating fully in ‘downstream’ biological functions. That is why organisms and ecosystems are particularly vulnerable to the crude, artificial genetically modified RNA and DNA created by human genetic engineers. It is also why genetic modification can probably never be safe.
1. Genetic modification done by human genetic engineers is anything but precise; it is uncontrollable and unpredictable, introducing many collateral damage to the host genome as well as new transcripts, proteins and metabolites that could be harmful.
2. GM feed with very different transgenes have been shown to be harmful to a wide range of species, by farmers in the field and independent scientists working in the lab, indicating that genetic modification itself is unsafe.
3. Genetic modification done by human genetic engineers is different from natural genetic modification done by organisms themselves for the following reasons: it relies on making unnatural GM constructs designed to cross species barriers and jump into genomes; it combines and transfers genes between species that would never have exchanged genes in nature; GM constructs tend to be unstable and hence more prone to further horizontal gene transfer after it has integrated into the genome.
4. Horizontal gene transfer and recombination is a major route for creating new viruses and bacteria that cause diseases and spreading drug and antibiotic resistance. Transgenic DNA is especially dangerous because the GM constructs are already combinations of sequences from diverse bacteria and viruses that cause diseases, and contain antibiotic resistance marker genes.
5. There is experimental evidence that transgenes are much more likely to spread and to transfer horizontally.
6. The instability of the GM construct is reflected in the instability of transgenic varieties due to both transgene silencing and the loss of transgenes, for which abundant evidence exists. Transgenic instability makes a mockery of ‘event-specific’ characterization and risk assessment, because any change in transgene expression, or worse, rearrangement or movement of the transgenic DNA insert(s) would create another transgenic plant different from the one that was characterized and risk assessed. And it matters little how thoroughly the original characterization and risk assessment may have been done. Unstable transgenic lines are illegal, they should not be growing commercially, and they are not eligible for patent protection.
7. There is abundant evidence for horizontal transfer of transgenic DNA from plant to bacteria in the lab and it is well known that transgenic DNA can persist in debris and residue in the soil long after the crops have been cultivated. At least 87 species (2 % of all known species) of bacteria can take up foreign DNA and integrate it into their genome; the frequency of that happening being greatly increased when a short homologous anchor sequence is present.
8. The frequency at which transgenic DNA transfers horizontal has been routinely underestimated because the overwhelming majority of natural bacteria cannot be cultured. Using direct detection methods without the need to culture, substantial gene transfers were observed on the surface of intact leaves as well as on rotting damaged leaves.
9. In the only monitoring experiment carried out with appropriate molecular probes so far, China has detected the spread of a GM antibiotic resistance gene to bacteria in all of its major rivers; suggesting that horizontal gene transfer has contributed to the recent rise in antibiotic resistance in animals and humans in the country.
10. GM DNA has been found to survive digestion in the gut of mice, the rumen of sheep and duodenum of cattle and to enter the blood stream.
11. In the only feeding trial carried out on humans, the complete 2 266 bp of the epsps transgene in Roundup Ready soybean flour was recovered from the colostomy bag in 6 out of 7 ileostomy subjects. In 3 out of 7 subjects, bacteria cultured from the contents of the colostomy bag were positive for the GM soya transgene, showing that horizontal transfer of the transgene had occurred; but no bacteria were positive for any natural soybean genes.
12. The gastrointestinal tract of mammals is a hotspot for horizontal gene transfer between bacteria, transfer beginning in the mouth.
13. Evidence is emerging that genomes of higher plants and animals may be even softer targets for horizontal gene transfer than genomes of bacteria.
14. The CaMV 35S promoter, most widely used in commercial GM crops, is known to have a fragmentation hotspot, which makes it prone to horizontal gene transfer; in addition. it is promiscuously active in bacteria, fungi, as well as human cells. Recent evidence also suggests that the promoter may enhance multiplication of disease-associated viruses including HIV and cytomegalovirus through the induction of proteins required for transcription of the viruses. It also overlaps with a viral gene that interferes with gene silencing, an essential function in plants and animals that protects them against viruses.
15. The Agrobacterium vector, most widely used for creating GM plants is now known to transfer genes also to fungi and human cells, and to share genetic signals for gene transfer with common bacteria in the environment. In addition, the Agrobacterium bacteria as well as it gene transfer vector tend to remain in the GM crops created, thereby constituting a ready route for horizontal gene transfer to all organisms interacting with the GM crops, or come into contact with the soil on which GM crops are growing or have been grown.
16. In 2008, Agrobacterium was linked to the outbreak of Morgellons disease. The Centers for Disease Control in the US launched an investigation, which concluded in 2012, with the finding: “no common underlying medical condition or infection source was identified”. But they had failed to investigate the involvement of Agrobacterium.
17. New GM crops that produce double-stranded RNA (dsRNA) for specific gene-silencing are hazardous because many off-target effects in the RNA interference process are now known, and cannot be controlled. Furthermore, small dsRNA in food plants were found to survive digestion in the human gut and to enter the bloodstream where they are transported to different tissues and cells to silence genes.
18. Evidence accumulated over the past 50 years have revealed nucleic acids (both DNA and RNA) circulating in the bloodstream of humans and other animals that are actively secreted by cells for intercommunication. The nucleic acids are taken up by target cells to silence genes in the case of double-stranded microRNA (miRNA), and may be integrated into the cells’ genome, in the case of DNA. The profile of the circulating nucleic acids change according to states of health and disease. Cancer cells use the system to spread cancer around the body. This nucleic acid intercom leaves the body very vulnerable to genetically modified nucleic acids that can take over the system to do considerable harm.
The serious harm to health and the ecological and agronomical impacts of glyphosate and glyphosate tolerant crops are the most thoroughly researched, and for which there is little remaining doubt. The same kind of evidence has now emerged for Bt crops and Bt toxins. Evidence that genetic modification per se is harmful is also convincing, and can be attributed to the uncontrollable process of genetic modification itself as well as the dangers from the horizontal transfer of the GM constructs, which can spread antibiotic resistance, create new pathogens and trigger ‘insertion carcinogenesis’, as well as taking over the body’s natural nucleic acid intercom to do harm.
There is a compelling case for banning all environmental releases of GMOs now, and with that the glyphosate herbicides. Action can be taken locally in communities, villages, towns, municipalities, regions, as well as nationally and globally. It must be done now; for time is running out. We need to shift comprehensively to non-GM sustainable ecological farming in order to feed ourselves under climate change. We the people need to reclaim our food and seed sovereignty from the corporate empire before they destroy our food and farming irreversibly.
Originally published at Institute of Science in Society.