Are genetically-modified organisms (GMOs) safe to consume?
I’m not an expert on the subject, by any stretch. But the answer must be more complex than just yes or no.
I’ve been presented with arguments on both sides, and I want to take some time today to research the evidence against Bacillus thuringiensis (Bt) in food.
I’ve chosen to formulate a response to this post on Facebook regarding pest resistant tomatoes using Bt technology, specifically regarding an article from Global Healing Center titled What is the Bt Toxin?
The text of the article is heavily slanted to provide an emotional pull toward one view. It begins and concludes by stating that Bt is aggressive, harmful, unfortunate, and toxic. But does the evidence support the claim?
What is Bacillus thuringiensis?
The article is mostly correct in its analysis of Bt. It is a bacteria that produces a particular protein which is toxic to insects.
But the article uses a simple scare-tactic to sway you toward hating Bacillus thuringiensis.
It correctly states that it is in the same family of bacteria as B. anthracis which causes anthrax, and B. cereus which causes food poisoning. They provide a link to a study that tells us this fact.
What they don’t care to mention is that the self-same study states clearly in the abstract that they demonstrate “widely different phenotypes and pathological effects.”
Clearly, being in the same family of bacteria has no bearing on what the effects of each particular bacteria does.
A simple fact, without which you might believe that Bt is as harmful as its family members. It is not.
What is Bt used for?
The article states correctly the methods and purposes of Bt use.
It can be sprayed on crops, or the piece of DNA responsible for creating the relevant protein can be modified into the DNA of the crops that are at risk of being destroyed by insects.
They toss in a completely unsubstantiated statement along with their statement of the facts.
They say that “neither method is positive for health or society.” But they fail to provide immediate evidence of this.
The article says that there is “a widely held belief that the safety of Bt has not been verified.”
They then provide a link to a single study from 1995 that suggests that we need more studies and more evidence before we make a decision on its efficacy and safety.
It is now 2016, a whole 21 years since that study, wherein there have been many more studies done.
To use that one study as evidence that we do not know enough would be fallacious and misleading.
Potential dangers of Bt
The article goes on to make more claims about the dangers. Here I’ll take a look at each one that has been given a source from a study.
It stays in your system
“Research has shown that the Bt toxin persists in the gastrointestinal tract of human-flora-associated rats weeks after exposure.”
This is definitely true, but here’s the article they use as their source: Persistence of Bacillus thuringiensis bioinsecticides in the gut of human-flora-associated rats.
The source study clearly indicates that “no other adverse effects were observed.”
So yes, it stays in your system. And no, it doesn’t have an adverse effect.
It is toxic to your lungs
The claim that “Bt has a toxic effect on the lungs and other organs” is backed up by a study, with scientists directly injecting high doses of Bt bacteria into the windpipe (trachea) of animals. Clearly, this is not how an average person interacts with Bt.
It can harm your eyes
One more claim is made, that Bt can “wreak havoc on the eyes” in rare cases.
The linked study doesn’t say in the abstract how that occurred, so I can’t say whether or not it was by high dosage of contact directly to the face, or through standard ingestion.
I’m also unclear on whether this was from the bacteria itself, or from the relevant pesticide protein. It’d be a jump to say that this is definitely from standard ingestion.
It is associated with B. cereus food poisoning
There’s another concern related to food poisoning.
But that study, too, does not actually say what the article writers were making it seem.
Because the bacteria that cause food poisoning and Bt are in the same family, they may be present at similar times.
But logic dictates that these are likely correlations, without causations.
Bt most likely does not cause the food poisoning.
This is one study that shows that B. cereus and Bt are sometimes co-present — meaning that when Bc is found, Bt might be there too.
But clearly, this does not equal evidence that Bc arises when Bt is present.
No such claim is made by the study.
Any such belief would be based on false information.
Insects can become resistant
Then there is one study that makes the claim that insects can become resistant to pesticides.
Assuming this is a given, what’s the outcome?
If we don’t use pesticides at all, there will be a large amount of pests.
If we do use them, there will be a small amount for a time.
If the insects become largely resistant, we will return to a situation with a large amount of pests.
And then, most likely, we would be able to locate another protein that causes harm to insects but doesn’t affect humans.
Summary of dangers
The article flatly fails to provide any substantial evidence of any sort that ties Bt to harmful effects caused by consumption of the bacteria on foods, or the protein within genetically-modified foods.
In fact, studies have been done, putting the protein in mammals at very high doses, and the protein does not cause adverse effects in those cases. Bt BRAD Chemistry and Human Helth Assessment, page IIB3.
Sure, we can question the validity of such studies. Who paid for them? What monetary advantage do they have to give this result?
So if you don’t trust the EPA (hey, I’m not saying I trust the EPA), then keep in mind that all other links thus far addressed were used as evidence against Bt in foods.
But the actual text of these studies seems to contradict the entire point being made by the article that wants us to distrust Bt foods.
If your best evidence itself is contrary to your own assertions, who should I believe?
The article under consideration falls flat on its face.
It makes several claims about Bt that are either unsubstantiated, or completely irrelevant to the topic.
Most of the scientific studies that are used to prove their point, prove exactly the opposite of their point.
Having a lot of questions about the safety of GMO foods and pesticides is perfectly fine and sane. We should ask hard questions of the growers of our foods.
But don’t take a solid stance against GMO and pesticides based on weak or false information.
The article clearly choses their words wisely when looking at studies, and leaves out very important facts like “but this doesn’t harm humans.”
It is an attempt to guide beliefs by saying scary things without providing the proper evidence for their claims.