Debunking Denialism

Defending science against the forces of irrationality.

Why Rachel Parent is Wrong About Genetically Modified Foods

Rachel Parent

Rachel Parent is a Canadian 15-year-old anti-GM activist who wants GM foods to be labelled. In an independently organized TEDx event at Toronto, she held a talk regurgitating almost all popular anti-GM claims in under 15 minutes. She claims to have been interested in GM crops since she was 12, yet the “research” she did involved reading anti-GM websites, not scientific papers. It is great that young women are getting increasingly interested in science and scientific research, but deceptive misinformation is a poor substitute for scientific integrity. In reality, all of her claims are either wrong or misleading: BT is safe for humans and have been used in organic farming, all plants contain their own “bug killers”, GM technology has been used to save the papaya and make rice prevent vitamin A deficiency, GM crops does increase total yield, is associated with less usage of dangerous pesticides, GM crops do not harm beneficial insects, farmers are not sued by accidental cross-pollination and GM crops are as safe as conventional crops. Even the paper she cites as evidence for GMOs causing allergies does not even mention GM crops. This post goes into detail in explaining why Parent is mistaken.

BT toxin is safe for humans and has been extensively in organic farming

BT toxin is a substance that is produced by bacteria and is only dangerous to a certain group of insect pests. This is because of its high specificity: it requires an alkaline stomach environment (humans and other mammals have acidic), a specific protease that cleaves the inactive precursor into the active toxin, a specific receptor on the gut surface that triggers the rupturing of the stomach lining.

It has been used extensively in both conventional and organic farming for many decades by spraying bacterial spores on the plants surface. However, with the help of recombinant DNA technology, scientists have been able to insert the gene that produces this toxin into the plant itself. It is a method that we know is safe and that we know work.

Plants cannot run, therefore they contain their own bug killers

Although it might seem odd at first that plants contain their own bug killers. However, this is actually very common. Most plants are stationary with roots into the ground and so they are not able to run away from their predators. Instead, they have evolved means of protecting themselves by using poisonous secondary metabolites. Among these are the solanine in conventional potatoes, spinasterol in spinach and coumarin in carrots. These can have neurotoxic effects, interfere with hormonal signaling and cross-links DNA. So far from being weird, plants making their own bug killers is the norm. These substances, like BT, occur in very small concentrations of course, so they are not dangerous to humans.

GM technology as been used to save papaya and to prevent deadly vitamin A deficiency

Parent focus exclusively on the two most common GM applications in agriculture: herbicide resistance and insect resistance. However, she does not bother to discuss other applications, such as virus-resistant papaya or rice that have more vitamin A.

The papaya ringspot virus (PRSV) almost exterminated papaya farming in Hawaii, which represented the vast majority of papaya production in the world. Researchers were able to genetically modify those papayas to make them resistant, and thus prevent the papaya production from collapsing. In other words, one of the reason that we still have papayas today is because of GM technology.

Vitamin A deficiency makes anywhere from a quarter of a million to half a million children go blind every year and half of them are dead within a year (WHO, 2014). With the help of genetic modification, it is possible to make rice produce a precursor of vitamin A. However, anti-GM activists and extreme government regulation has stifled the process of making this Golden Rice available to farmers (Potrykus, 2012).

Industrialization and monocropping due to Green Revolution, not GM crops

Parent complains about how food has become industrialized and grown as mono cultures. However, this is a result of the Green revolution, not GM crops. During the 1940s, 50s and 60s, large advances in conventional agriculture, such as stringent selection, chemical fertilizers and improved pesticides saved many millions from starvation.

There are hundreds of independent studies on GMOs

When scientists or scientific skeptics use accumulated scientific knowledge to disprove the claims made by anti-GM activists, these activists usually claim that all of these studies are just funded by Monsanto. However, this is neither true nor relevant. There are hundreds of independent studies on GMOs not founded by the industry and a lot of them can be found by searching the GENERA database.

What is the purpose of genetic modification?

Parent, after deploying common anti-GM tactics, raises the rhetorical question of what the purpose of GM crops actually are. The answer is that the purposes are many: reduced starvation, improved food security, increased yields, deceased food prices and combat human dietary deficiencies such as vitamin A deficiency, the prevention of cyanide damage from e.g. cassava, bioremediation of salty farm land, production of medications and so on.

GM crops show increase total yield

A recent meta analysis by Klümper and Qaim (2014) looked at almost 150 research papers investigating yield improvements for genetically modified soybean, cotton and maize. The results were clear: the average yield increase was 22%. This supports previous research that showed a 24-37% increased yield for GM cotton in India (Qaim, Matin Subramanian and Sadashivappa, 2009; Kathage and Qaim, 2012).

A common tactic by anti-GM activists is to ignore all of this research that shows that GM crops increases total yield by referring to an investigation by the Union for Concern Scientists. However, this study looked at intrinsic yield not total yield. Intrinsic yield, which roughly corresponds to the number of corns per cob, has not changed that much regardless of agricultural technology, but his is not the kind of yield that farmers are mostly interested in. They are interested in total yield, which as we have seen, has increased substantially.

GM crops contribute to decrease in dangerous pesticide usage

The Klümper and Qaim (2014) meta analysis shows that average overall pesticide use has decreased by 37%. This is primarily driven by the fact that dangerous pesticides has been replaced by plants that produce their own BT and dangerous herbicides has been replaced by the less harmful herbicide glyphosate. Now, the usage of glyphosate has indeed increased, but this is coupled to a decrease in more harmful herbicides. So it is not just about amount. Furthermore, the patent for glyphosate owned by Monsanto expired in 2000, so independent companies have been able to produce it for almost to 15 years and so the added competition has deceases prices for this herbicide.

Superweeds are a problem for all forms of agriculture and there are GM solutions

All herbicide use leads to resistance. It is the inevitable consequence of evolution. When resistance to herbicide occurs in conventional agriculture, farmers just switch herbicide. This is not a problem specific for GM crops. Furthermore, having herbicide resistance is only useful when growing on farm land. It offers no benefit for wild species outside farm land.

For insect resistance, it is possible to mitigate this different ways, such as pyramiding of resistance genes and insect refuges. Pyramiding is done by including several genes for BT that produce a slightly different version of the toxin. So even if a certain insect pest is resistant to one of them, the other one will kill it. Insect refuges consists of sections of non-GM crops that are vulnerable to the insect pest in question. This will keep alive the insects that are homozygous for susceptible alleles, and so insects offspring that are homozygous for the resistance allele are less likely to arise.

GM technology for resistance to insects pests do not harm beneficial insects

Parents claims that “weed killers” has killed off almost all milkweed, a central food source for the larvae of Monarch butterflies. However, this is a weak argument for several reasons. First, this has to do with herbicide use and not GM crops. Second, herbicides are sprayed on the farm land, not all over the countryside, so impact should be limited. Third, research has shown that the impact of GM crops on Monarch butterflies is deemed negligible.

Colony collapse disorder (CCD) not related to GM crops

There has been report of extensive bee death around the world in recent years. However, this has little geographical overlap between GM crops and a large number of studies has been done that shows that the evidence favors a rejection of a causal connection between GM crops and bee death (Lemaux, 2009). A meta analysis by Duan, Marvier, Dively and Huang (2008) looked at 25 studies investigating a potential relationship between GM crops and bee deaths and concluded that there was no causal connection.

Farmers are not sued for accidental cross-pollination

It is very easy to tell if GM crops growing in a farm has gotten there by accident or intentionally. If it is accidental, you would expect a small proportion (a few %) of plants to have the GM trait and most of them should be hybrids between GM plants from a nearby farm and the conventional plants grown on the farmers grounds. If it is intentional, the vast majority of plants should have the GM trait and they should be pure GM crops and not hybrids.

As a result, companies making GM crops do not sue people for accidental cross-pollination. The alleged example that anti-GM activists usually trot out is that of Monsanto Canada Inc. v. Schmeiser. However, this was not about accidental cross-pollination, but rather about intentional planting of patented GM crops. Here is how McHughen and Wager (2010) explains it:

The fear about a company claiming ownership of a farmer’s crop based on the inadvertent presence of GM pollen grain or seed is also widespread and equally unfounded. The usual cited source for such fears is the 2001 Monsanto versus Schmeiser litigation, in which the company sued Mr Percy Schmeiser, a Canadian farmer, for growing their Roundup Ready canola without an appropriate license. As his defense, Mr Schmeiser claims Monsanto’s Roundup Ready canola turned up on his farm due to either cross-pollination from ‘. . .wind or insects, seed blown from passing trucks, or dropping from farm equipment, or swaths blown from neighbours’ fields’. In any case, Mr Schmeiser claims he was entirely innocent of the charges and in fact Monsanto’s seeds have ‘trespassed’ and contaminated his own canola. When the trial judge ultimately ruled in favor of Monsanto, word spread that Mr Schmeiser lost the case even though he was the innocent and wronged party. The court record shows, however, that it was not just a few seeds from a passing truck, but that Mr Schmeiser was growing a crop of 95–98% pure Roundup Ready plants, a commercial level of purity far higher than one would expect from inadvertent or accidental presence. The judge could not account for how a few wayward seeds or pollen grains could come to dominate hundreds of acres without Mr Schmeiser’s active participation, saying ‘. . .none of the suggested sources could reasonably explain the concentration or extent of Roundup Ready canola of a commercial quality evident from the results of tests on Schmeiser’s crop.

Parent makes a comparison with a neighbor spray painting his or her house and some of it gets onto your house by mistake. Should the neighbor force you to pay for it? Of course not, but if you sneaked into the neighbors garage and stole the paint and spray painted your own house, then you should have to pay for it.

There are also other things that are important to keep in mind, such as the fact that pollen does not spread that far, a lot of GM crops are obligate self-fertilizers and genetic modifications in the chloroplast does not spread via pollen (only via the mother plant).

It is also worth noting that Parent, like many anti-GM activists, use the emotionally manipulative phrase “contamination” to refer to accidental cross-pollination from GM crops.

Pediatrics paper on allergies do not even mention GMOs

Parent claims:

Another study showed that GMOs were actually related to allergies. The study was done by the Journal of Pediatrics. They showed food allergies in 1 in 12 children. Is there a connection?

Although few study details are mentioned, it is possible to find the original paper. By performing a Google search for the 1 in 12 figure, child allergies and GMOs, the GMO Awareness website was found. On this website, the journal is indeed called “Journal of Pediatrics”. However, it links to an Today Health story about it, where the lead author and journal are specified. It turns out that the original paper is by Gupta and colleagues (2011) and the journal is Pediatrics, not the Journal of Pediatrics.

Guess what is so interesting about this research paper? It does not even mention GMOs. In other words, Parent claims that this research shows that GMOs are related to allergies, when, in fact, the paper does not even mention GMOs or GM crops. Although Parent probably did not do this intentionally and probably just bought into the GMO Awareness website, it shows to what lengths anti-GM activists go to obfuscate and provide misinformation about GM crops.

Other countries have banned GMOs. So what? Some have also banned same-sex consensual love

Parent attempts to incite doubts about GMOs by pointing out that other countries require labeling or has banned it. However, this is a thinly yield application of the appeal to popularity fallacy. Just because a certain move is popular does not mean it is rational. For instance, being gay is punishable by imprisonment in over 70 countries and it is given the death penalty in at least five other countries. Yet no serious person would argue that this means that the U. S. should enact these laws. Instead, laws should be based on rational arguments and empirical evidence.

Rats genetically prone to cancer as they grow old gets cancer as they grown old

A study carried out by Séralini and colleagues claim to have shown that GM corn gives rats cancer. However, this has several overt methodological flaws: (1) the rates strain spontaneously develops cancer as they grow old and researchers kept them alive for a very long time, (2) there was little control for confounders, (3) there was no dose-response, (4) they used inappropriate statistical treatments and several other issues. Similar problems can be found in most papers by anti-GM activists.

GM crops probably safer than conventional crops

Parent makes the popular claim that “we are lab rats!”, but in reality, GM crops are probably safer than conventional. Here is a popular table on GM crops that is often used here on Debunking Denialism.

Traditional plant breeding Production of GM crops
What is the size of the genetic changes? Genetic recombination causes thousands of large genetic changes. Adding or modifying one or a few genes qualifies as small genetic changes.
How precisely are the changes done? Very low precision because all breeders have to look at is the phenotype. Extremely high precision because scientists can use biotech techniques.
How well-known are the genetic changes? Unknown since you are only looking at the phenotype. Highly characterized, both by virtue of the techniques involved and because of regulation requirements.
How long does it take? Decades, unless you mutate seeds with chemicals or radiation (which still qualifies as traditional plant breeding by regulators). Very fast.
When can they be released? Right when they are made. No government regulation. After 10+ years of intense toxicological and ecological testing.

In other words, GM crops involve fewer changes, more precise changes, more well-known changes and more tested changes.

Five reasons why GMO labeling is a bad idea

Scientific American ran an article a while back on why GMO labeling is a bad idea: it increases misconceptions about GM foods, it limits consumer options, increases consumer food costs, gives farmers more administrative work and it stigmatizes important biotechnological solutions.

The reason why food stuff that contains salt, nuts or calories are labeled is because they have important health consequences for consumers: it help people avoid unhealthy foods that increase obesity, greatly reduces the risk for people with fatal allergies to nuts and people with heart disease who need to limit their salt intake. However, GMOs are not things, but rather methods. The difference between GM corn and conventional corn is not the content, but the method used to produce them. To be true, GM corns contain resistance genes, but those are just stretches of nucleotides, just like any other piece of DNA.

Parent attack the integrity of researchers

After a long tirade of falsehoods about genetically modified crops, Parent makes the following, astounding statement:

To quote Dr. David Suzuki: “Any politician or scientist that tells you these GMO products are safe is either very stupid, or lying.

Despite her own admission that she “is not a scientist” and “do not hold a university degree”, she thinks she is qualified to not only make categorical pronouncements on GM crops without having read or understood the research, but to also to call scientists are “very stupid” or “lying”.

Clearly, there is room for considerable intellectual improvement on her part.

References and further reading

Qaim, M., et al. (2009). Commercialized GM crops and yield. Nat Biotech 27(9): 803-804.

Klümper, W. and M. Qaim (2014). A Meta-Analysis of the Impacts of Genetically Modified Crops. PLoS ONE 9(11): e111629.

Kathage, J., & Qaim, M. (2012). Economic impacts and impact dynamics of Bt (Bacillus thuringiensis) cotton in India. Proceedings of the National Academy of Sciences, 109(29), 11652-11656.

Lemaux, P. G. (2009). Genetically Engineered Plants and Foods: A Scientist’s Analysis of the Issues (Part II). Annual Review of Plant Biology, 60(1), 511-559.

Duan, J. J., Marvier, M., Huesing, J., Dively, G., & Huang, Z. Y. (2008). A Meta-Analysis of Effects of Bt Crops on Honey Bees (Hymenoptera: Apidae). PLoS ONE, 3(1), e1415.

McHughen, A., & Wager, R. (2010). Popular misconceptions: agricultural biotechnology. New Biotechnology, 27(6), 724-728.

Gupta, R. S., Springston, E. E., Warrier, M. R., Smith, B., Kumar, R., Pongracic, J., & Holl, J. L. (2011). The Prevalence, Severity, and Distribution of Childhood Food Allergy in the United States. Pediatrics.

Potrykus, Ingo. (2010). Regulation must be revolutionized. Nature, 466(7306), 561-561.

WHO. (2013). Micronutrient deficiencies: Vitamin A deficiency. Accessed: 2014-12-20.

7 responses to “Why Rachel Parent is Wrong About Genetically Modified Foods

  1. Jose M. S. December 20, 2014 at 22:24

    Very interesting information. I’m glad I found this because I like to know, as much as someone that’s not an expert can know, what are the arguments in favor and against GM. However, I do have a question (not without a dose of criticisms): how is this blog entry different to some other attempts to disqualify the opposite opinion by criticizing an obviously poor and misleading “investigation” by an individual, as if it were the hole contrary opinion?

  2. guardian12345 December 21, 2014 at 09:09

    Most 15 year olds don’t know every much – why should she be any different?

  3. john robbins February 18, 2015 at 02:28

    Why doesn’t the industry voluntary label foods that are been genetically modified for consumers to choose. What are they afraid of.

    • Emil Karlsson February 18, 2015 at 20:14

      There are at least five reasons why GMO labeling is a bad idea:

      – Increase misconceptions about the health effects of GM foods
      – Limit consumer options
      – Increased food cost for the consumer
      – More administrative work for farmers
      – Increase stigma against beneficial technology

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