Bt isn’t harmful to humans — Bt proteins can only exert toxicity if they are eaten and subsequently bind to specific gut receptors that are absent in most non-pest species, including humans.
Glyphosate isn’t harmful to humans — it operates by disrupting the shikimate pathway, and human beings don’t even have a shikimate pathway.
Synthetic fertilizer isn’t harmful to humans — plants need those macronutrients and can quickly use them in synthetic forms, and we need them to grow enough food to feed the world.
What’s wrong with the logic here? Clearly, each case relies on overly simplistic reasoning: there is no direct negative effect, therefore there is no negative effect.
The truth is more complex: there may not be a direct negative effect, but there are some, or many, indirect negative effects, and these indirect negative effects can compound into a large overall negative effect.
Take Bt. Yes, Bt proteins themselves are not toxic to humans. But as researcher Joe Lewis and farmer/researcher Alton Walker discuss in this month’s interview, having Bt traits in crops like cotton disrupts the natural balance of predator and prey insects. What this has meant in cotton is that while farmers no longer need to spray pesticides to guard against bollworm, they now need to spray the same amount of pesticide to protect the crop from stink bugs.
According to Lewis, “When you don’t have Bt, and you have feeding activity by bollworms in the field, that stimulates the plant to start producing some nasty chemicals, in addition to the odors that they produce to recruit beneficial insects. Those nasty chemicals help prevent the stink bug. It has a cross interaction. Not only does it slow down the boll worm — it prevents the stink bug from breaking in. But we are losing that attribute. Bt doesn’t reduce the amount of pesticides conventional farmers have to spray.”
So, while humans aren’t directly negatively affected by the Bt protein — a bacterial gene that is inserted into plants — we are directly affected by the pesticides that continue to be used because of Bt’s misbalancing effect on the environment. Cotton is just one example of a crop that incorporates Bt traits (and cotton is consumed by humans — cottonseed oil was used to make Crisco for years and is still a part of many ultraprocessed food products).
Now, there are obviously other factors involved in why farmers choose to use genetically modified seeds and inputs like herbicides and pesticides. While not ideal, it’s one thing to use them occasionally as a tool to protect a crop, and thus to protect the farm business. But this isn’t how these products are generally used in the real world. The real solution is to change our way of thinking — away from simplistic tools like pesticides and toward a holistic, ecologically focused mindset that seeks to keep the entire ecosystem in balance.
And that’s the view from the country.