We endorse that stance, and are opposed to GM foods for two primary reasons: the weakness of the U.S. regulatory structure for approval of GM foods, and the scientific uncertainties surrounding their long-term safety and sustainability.
Traces of herbicides used with GM crops were found in pregnant women and fetuses.
The study also found traces of a natural pesticide (Bt) generated inside certain GM crops
The same natural pesticide (Bt) is sprayed on some organic and non-GM conventional crops, but little if any gets inside people that way.
- The synthetic, GM-related herbicides likely pose a much greater risk than the natural pesticide (Bt) ever could.
A recent report from Canada raises new questions about the adequacy of regulations governing GM food crops.
The study tested blood from pregnant women and fetuses and found traces of synthetic and natural pesticides associated with GM food crops.
The finding of synthetic pesticide traces, while deplorable, was not remarkable, as such chemicals are commonly found in mothers and infants.
Ironically, the detection of likely harmless traces of a natural pesticide generated inside certain GM food crops raises more concern … because it reveals the inadequacy of the regulations governing approval of GM foods.
Let's examine the study, and whether its findings should worry mothers … or any other people.
Canadian doctors find pesticide from GM crops in women and fetuses
Earlier this year, doctors at the University of Sherbrooke Hospital Centre in Quebec set out to see whether pregnant women and their fetuses were carrying synthetic herbicides and a natural pesticide associated with some GM crops (Aris A, Leblanc S 2011).
They were looking for residues of two very different kinds of pest control agent:
Two synthetic herbicides used primarily to protect certain patented GM food crops.
A “biocide” (natural insecticide) generated inside some GM food crops by added genes from a bacterium.
The synthetic herbicides (weed killers) in question are glyphosate (e.g., Monsanto's “Roundup”) and gluphosinate (e.g., Bayer Corp's “Liberty”), which are used on crops genetically modified to resist them, allowing farmers to apply them freely.
High exposures to glyphosate harm human placental and embryonic cells, and in rats, damage fetal skeletons and the reproductive system of males..
And in mice, high doses of gluphosinate appear to raise the risk of congenital malformations, retard the growth of embryos, and increase their rates of death.
The natural biocide they looked for was a protein toxic to certain insect pests. This protein is produced naturally by a bacterium known as Bacillus thuringiensis (“Bt”), whose relevant genes are added to the genetic code of some food crops.
For more than 50 years, organic and conventional farmers have used Bt spores or the crystalline “CRY” proteins produced by Bt microbes, as natural alternatives to chemical pesticides.
The Bt microbe – which occurs naturally in soils, beaches, tundra, and other ground materials worldwide – produces crystalline “CRY” proteins that kill very specific, crop-eating or crop-damaging insects.
There are many different strains of Bt, and each one produces a different CRY protein that is toxic to a specific pest insect …and sometimes to certain close relatives.
Results demand more study
The Canadian doctors took blood samples from 30 pregnant women and from 39 non-pregnant women.
Blood tests found traces of the two synthetic herbicides used with GM crops – glyphosate and gluphosinate – or a breakdown product of gluphosinate (3-MPPA) in the pregnant and non-pregnant women alike.
Fortunately, the levels of gluphosinate found in this study (53.6ng/ml) were much lower than the doses that produced harm in mouse tests (10ug/ml).
Traces of Bt CRY protein were detected in pregnant and non-pregnant women and in umbilical cords.
Specifically, traces of Bt CRY protein were found in the blood of 27 out of 39 non-pregnant women (69 percent).
In the pregnant group, Bt CRY protein was found in the blood of 28 out of 30 women (93 percent).
And Bt CRY protein was found in 24 out of 30 umbilical cords (80 percent). Thus, Bt CRY protein crossed the umbilical barrier.
It's presumed that the synthetic herbicides and the Bt CRY protein both came from eating GM crops and from meat, milk, and eggs from livestock fed GM crops.
As the Canadian team wrote, “This is the first study to highlight the presence of pesticides associated with genetically modified foods in maternal, fetal and non-pregnant women's blood.” (Aris A, Leblanc S 2011)
Calling for action, the team said: “Given the potential toxicity of these environmental pollutants and the fragility of the fetus, more studies are needed.” (Aris A, Leblanc S 2011)
Synthetic vs. natural pesticides: The risk divide seems wide
We couldn't agree more about the potential toxicity of the synthetic herbicides … because of existing animal evidence and because modern mothers already pass, unwillingly, a variety of synthetic toxins to fetuses and nursing infants.
In contrast, the available evidence from studies in humans and other mammals suggests that risks to fetuses from umbilical traces of Bt CRY protein are likely to be far lower … though that hypothesis is nearly impossible to test in an ethical way.
Most Bt biocides contain either the CRY proteins or spores that will produce live Bt bacteria inside the pest. When consumed by a susceptible insect, Bt's CRY proteins kill it quickly by creating holes in the lining of its gut cells, while ingested Bt spores will germinate inside a target insect and cause death within a few days.
The U.S. EPA says that placing Bt on food crops is safe for people, animals, and the environment, and the agency has exempted it from special restrictions or review requirements.
Beneficial insects are rarely harmed by Bt. For example, a headline-making study, which seemed to show that Bt produced inside certain GM crops was harming Monarch butterflies, has been convincingly refuted.
Bt's high degree of specificity – and the fact that it produces less resistance in pests – makes this natural “biocide” a highly attractive alternative to broadly poisonous synthetic pesticides.
Are GM crops safe? It's a question requiring rigorous, ongoing regulation
To date, there is little or no evidence that currently approved GM foods have harmed any of the billions of humans or animals that have been eating them for decades.
But every GM food is different, and we cannot predict the safety of future ones based on the past record.
However, even conventionally hybridized crops raise concerns unknown to most consumers.
Many of the commercial seeds planted by organic and conventional farmers were the result of a standard process that uses radiation or toxic chemicals to induce thousands of random gene mutations.
Randomly mutated test seeds are planted to identify the ones that produce plants with commercially advantageous changes.
Compared with gene splicing, this approach is far less precise … and just as likely to produce “hidden” mutations that are undesirable from a health/nutrition standpoint.
Of course, Mother Nature also induces random gene mutations in food crops, via cosmic rays, ground radiation, and exposure to natural chemicals … which doesn't make the results of that wholly natural process inherently safer to consumers.
Putting those issues aside, U.S. regulations concerning GM crops are weak and biased toward bio-tech agribusinesses … both when it comes to scientific reviews of proposed new GM crops (or animals), and to post-approval monitoring of GM crops' human and environmental health impacts.
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