RNA Pesticides — A Potential Revolution in Agriculture, But With Risks

For decades, agriculture has tried to find new ways to strike a balance between the necessity of protecting crops from pests and the environmental and ecosystem damage caused by pesticides.

Traditional chemical pesticides often end up damaging many other species beyond those they specifically target, leading to unintended damage to human and animal health.

This scattershot approach may finally have a solution as testing begins on a highly targeted strategy: RNA-based pesticides.

Will these new products finally stop the poisoning of fields with “all-in-one” traditional products? How effective are they?

Or can RNA be yet another genie out of the bottle with unintended consequences? Let’s try to answer these questions.

Key Takeaways

  • Agriculture grapples with the dual challenges of pest control and environmental harm caused by chemical pesticides.
  • RNA-based pesticides are suggested as a highly targeted alternative, with a potential solution against collateral damage.
  • But despite promising selective action and environmental safety, concerns exist regarding unforeseen consequences and large-scale deployment.
  • While proponents examine its potential, cautious evaluation is essential given the complex ecological implications.
  • The balance between risk and reward needs thorough scrutiny before widespread adoption.

Kill Or Be Killed – The Problem With Saving Crops From Pests

As humans keep increasing in number, protecting crops from pests such as insects (mostly aphids), bacteria, and fungi has become an indispensable need.

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In the 1940s, the development of DDT (dichloro-diphenyl-trichloroethane) forever changed the yield of crops, revolutionizing human nutrition. However, once its use became widespread enough, it started becoming clear how DDT was anything but harmless and that its extended use brought with it negative consequences.

Toxicological studies found it had a residual activity on humans and wildlife, causing serious health concerns that eventually led to its discontinuation.

Modern pesticides are less toxic than DDT but are still quite harmful. Their use must be controlled, and while it’s highly regulated, unintended (or even “acceptable”) consequences still cause damage.

From pests developing resistance, to other species being killed, or even unintended population booms putting an ecosystem out of balance — pesticides generally do not have the one-off effect they are created for.

And since ecosystems depend on pollinators, the damage caused by a pesticide often extends across different crops. Today, the fungus Botrytis cinerea has developed an incredible resistance to all fungicides and can now cause up to $100 billion of product loss each year.

A Brief History of RNA Pesticides

Although RNA-based technologies were put under the spotlight for their use during the COVID-19 pandemic, the use of RNA-interference (RNAi, also known as Post-Transcriptional Gene Silencing – PTGS) for various applications has been known for nearly two decades.

The science is now being put to the test: In 2017, Monsanto Co. obtained approval from the US Environmental Protection Agency (EPA) to experiment on corn.

However, it was only in 2019 that RNAi-based pesticides were officially introduced to the world, discussed in Paris, France, during the aptly named Conference on RNAi Based Pesticides, and supported by the Organization for Economic Co-operation and Development (OECD).

This conference included the presence of many experts from the world of industry, academia, and regulatory boards and led to the development of a document, updated in August 2023, known as Considerations for the Human Health Risk Assessment of Externally Applied dsRNABased Pesticides.

Today, newer production strategies substantially reduce the price of RNAi pesticides, making them commercially viable. Projects such as ViVe Beet and companies such as GreenLight Biosciences and RNAissance Ag successfully experiment with this technology that is now readily available at a much more affordable price.

How Does RNAi-Based Pesticides Technology Work?

The mechanism of action of RNAi-based pesticides depends on the production of specific sequences of double-stranded RNA (dsRNA). Once a pest absorbs this genetic message, targeted genes — ones that are necessary for the production of essential proteins — will be suppressed within the creature.

The final effect of this cascade of events is inhibiting some vital biological process of the pest, leading to its final demise.

The main advantage of RNA technologies is, in theory, that they are extremely selective for that specific biological organism, so the risk of affecting unintended targets is minimal.

Another advantage is that genetic pesticides based on RNAs do not pollute the environment, and if they do enter the environment, they are chemically unstable, so they degrade quickly.

In terms of effectiveness, RNA pesticides seem superior to traditional ones. First, they can be engineered to specifically target any kind of pest, from insects to fungi, bacteria, and even difficult-to-target viruses.

New, highly specific RNAi-based pesticides can be developed quickly, which means they can be used even when time is not on the cultivator’s side – such as when an unexpected infestation occurs.

They can even target an organism that has developed some degree of resistance simply by targeting another region of the same gene (or a different gene altogether).

So the question is, should RNA pesticides be “field-tested”?

A Brief Look At The Possible Risks of RNA Pesticides

Many studies confirmed that the risk of toxicity exerted by RNAi-based products is likely to be very low, regardless of how they are absorbed (e.g., inhalation, skin contact, or even ingestion).

However, caution is never enough regarding a technology we still know very little about — especially since it poses to be used on a very large scale.

The report ‘Gene-Silencing Pesticides‘ (PDF) by Friends of the Earth contains many criticisms of the new field, with a ‘Sorceror’s Apprentice’ conclusion that states: “It is difficult to overstate the hubris in assuming that we can safely release agents designed to induce genetic modifications in organisms in the environment without causing unintended consequences.

“Rather than continue on a pesticide treadmill in which farmers use new formulations of toxic pesticides to deal with resistant pests, ecological farming methods offer a true solution.”

One criticism that seems worth highlighting is that it’s not about the risks that we do know; it’s the ones that we don’t know.

We still have to face a very large knowledge gap that limits our ability to understand all the consequences of gene manipulation.

The number of potentially similar organisms that could be affected by the same RNA sequence may be enormous.

The Bottom Line

RNA pesticides are, by definition, a weapon to kill some organisms. No technology built to destroy something is devoid of risks. Downplaying them or outright ignoring them in favor of their enticing effectiveness is highly irresponsible, especially since the consequences could be disastrous on a global scale.

However, it’s not like the alternative we’re currently using is safe or clean.

It comes down to properly evaluating both the risks and the benefits of this new technology — and being aware of how consequences may not be visible for years or decades.

We cannot draw a conclusion about the power — in either direction — of this technology, but we offer it up for visibility.

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Claudio Buttice
Data Analyst

Dr. Claudio Butticè, Pharm.D., is a former Pharmacy Director who worked for several large public hospitals in Southern Italy, as well as for the humanitarian NGO Emergency. He is now an accomplished book author who has written on topics such as medicine, technology, world poverty, human rights, and science for publishers such as SAGE Publishing, Bloomsbury Publishing, and Mission Bell Media. His latest books are "Universal Health Care" (2019) and "What You Need to Know about Headaches" (2022).A data analyst and freelance journalist as well, many of his articles have been published in magazines such as Cracked, The Elephant, Digital…