17
Mar
Genetically Modified Microorganisms Threaten Human and Soil Health; Full Extent of Hazards Not Regulated
(Beyond Pesticides, March 17, 2026) An article in Microorganisms by researchers from the U.S., Israel, and Australia analyzes the adverse health and environmental effects of genetic engineering and genetically modified organisms (GMOs), specifically genetically modified microorganisms (GMMs). As the authors state, the prevalence of genetic engineering has “accelerated the creation and large-scale environmental release†of GMMs, which “present unique, long-term risks to human and environmental health.†One of the authors, André Leu, DSc, spoke at the first session of Beyond Pesticides’ National Forum Series: Forging a Future with Nature in 2023. (See recording here.)
This review provides risk scenarios of GMMs, showing the threat to ecological systems, particularly within the soil, and human health. As GMMs are “biologically active, self-replicating entities capable of rapid mutation and global dispersal†they present greater risks, and current regulatory frameworks do not adequately assess their potential harm. Genetically altering microorganisms, the most complex and diverse systems in biology, and creating new gene combinations with unknown implications, “has the potential to disrupt the functions, diversity, interactions, and impacts of microbes and microbiomes,†the researchers note. They continue: “This puts human and environmental health at risk. Worst-case scenarios include the promotion of diseases, risks to species survival, and damaged or collapsed ecosystems.â€
This is not a theoretical issue. As the authors point out, currently there are two prominent companies that have publicly announced the use of GMMs on large amounts of agricultural land. Pivot Bio has used their product, Proven®, and released “GM bacteria on nearly 5 million acres, with as many as 5 trillion microbes per acre†to continually fix nitrogen, while Bayer has “released a seed treatment called Poncho®VOTiVO® 2.0 (now sold by BASF) that contains GM Bacillus thuringiensis.â€
Importance and Background
Currently, consistent and extensive regulations for GMOs and GMMs are deficient, with the regulatory processes for assessing organisms that have had their genetic material (DNA) intentionally changed varying around the world. “Pre-release safety testing, assessments for human and environmental impact, and monitoring frameworks are lacking,†the authors say. They continue: “In the US, GMMs for commercial use are primarily regulated by the Environmental Protection Agency (EPA) as toxic substances, which is ill-suited for biological organisms. In addition, most other GMMs (not for commercial use) are unregulated and untracked.†(See more below on regulatory deficiencies.)
Microorganisms play an important role within ecosystems. Types of microorganisms include bacteria, archaea, fungi, viruses, bacteriophages, and protists, all of which can live as a collection in a microbiome. These systems require balance to adequately promote crucial life functions, whether that is soil microbiomes supporting healthy plants and food crops or the human gut microbiome supporting immunity, metabolism, detoxification, and resistance to infection.
“[N]atural microbiomes have proven critical to human and environmental health, and GMMs carry a high level of unpredictability with the potential to produce long-term, significant ecological threats,†the researchers share. They continue: “The use of GMMs in agriculture, including biological control agents for plant disease and bioremediation for soil, is expanding rapidly. The global market value in 2021 was $10.25 billion; it was predicted to nearly triple to $29.31 billion by 2029. Although most applications use naturally occurring microbes, the use of GMMs in agriculture is expected to increase dramatically.†Given the questions regarding an adequate regulatory framework, this expansion exacerbates the potential threat to human and soil health, as well as all wildlife.
Health and Environmental Implications
The unpredictability of genetic engineering presents risks that are not adequately addressed prior to the release of GMMs or GMOs. As a result, the consequences of allowing these organisms to enter the environment could be “widespread, long-term, and difficult or impossible to remediate.†The impacts could range from antibiotic resistance, cancer, and developmental delays to fully altered ecosystems.
As the review indicates, there are “at least five unique characteristics of microbes that make the regulation of GMMs more difficult—and potentially more impactful—than genetically modified plants and animals.†This includes:
- “Rapid replication. Unlike plants and animals that may require growing seasons and gestation periods to pass down traits to offspring, microbes under ideal conditions can double their numbers in as little as 20 minutes.
- Challenges with containment. Microbes are not easily contained. They can travel to distant and unexpected ecosystems and hosts and interact with a wide range of other microbes and organisms.
- Gene transfer. Microbes might readily transfer their genes to other microbes (known as horizontal gene transfer), or receive genes transferred from GM or non-GM microbes. If they confer advantages, the transferred genes may continue to be passed on from mother to daughter cells, exponentially increasing their count.
- Microbiomes are life-critical. Microbial communities are critical to the health and function of humans, animals, plants, and ecosystems around the planet.
- Unknown complexities. Science has only identified perhaps one percent of the estimated one trillion microbes on the planet. Furthermore, we have only begun to map the complex relationships within and between microbiomes, hosts, and ecosystems.â€
Gut Microbiome
The gut microbiome is critical to health, allowing for the “resilience and survivability of mammals over evolutionary history†through roles in nutrient absorption, immune function, transient and chronic inflammation, intestinal barrier integrity, metabolism, mental health, and more. GMMs can cause imbalances in the gut microbiome, promoting disease within the gastrointestinal system.
Infant Health
As addressed on Beyond Pesticides’ resources page for children’s health, early life is a critical time in which “windows of vulnerability†occur, with critical implications for long-term health, including preconception. A child’s microbiome starts with the mother, as microbial information is passed down. “The first three years of life are key in terms of the development of the host-microbe interactions, which directly impact the development of the baby’s immune system, gut health, and neurological development,†the authors of the current review say.
The gut microbiome within infants is even more crucial, as it “protects against pathogenic infections, promotes gastrointestinal development, and coincides with healthy neurological development. The infant microbiome helps build an informed and precise immune system—one that attacks infections, but does not attack harmless substances, as in the case of food allergies, or self-tissues, in the case of autoimmunity.†GMMs, however, can disrupt these systems and cause long-term health implications.
Oral Health
Within the human body, the oral microbiome is the second-most biodiverse microbial population, housing at least 770 species. The review states: “When balanced, the oral microbiome prevents disease, resists pathogenic infections, provides multi-layer immune defenses, and reduces inflammation. Friendly oral bacteria contribute up to 25% of a person’s total daily needs of the critical blood-pressure-lowering chemical, nitric oxide. On the other hand, an imbalanced oral microbiome increases the risk of heart attack by nearly 50%. It not only promotes cavities, gum disease, and heart disease, but an imbalanced oral microbiome has also been implicated in brain inflammation, lung infections, diabetes, head and neck cancers, preterm birth, and inflammatory joint disease.â€
Soil Health
The microbes in the soil are important for soil formation as they perform crucial soil processes and break down organic matter, weather minerals, fix nitrogen, and contribute to soil structure. “However, introducing the unpredictable element of genetically modified microbes to enhance certain capacities, such as nitrogen fixation, into ecosystems already under considerable stress introduces exceptionally high risks,†the researchers point out. “Nevertheless, GMO microbes have been, and are currently released at a large scale (millions of acres) into many parts of the world without rigorous risk assessments on how they might impact all the above processes, long-term or short-term.†Risks include heightened pathogenicity (causing disease), additional emergence of pests or weeds, and resistance.
“There is an even greater risk in unleashing genetically modified microbes into soil ecosystems because microbes can adapt and evolve continuously through processes such as horizontal gene transfer,†the authors note. “Through this mechanism, a modified microbial gene from a GMM could be transferred to a native soil microbe, altering its genome and its ecological niche.â€
GMOs and GMMs in Agriculture
One of the largest concerns related to genetic engineering is resistance, which is not merely a hypothetical threat. Genetically modified crops with herbicide resistance have led to herbicide-resistant “super weeds†developing naturally as a response. While attempting to create crops that can be sprayed with high amounts of herbicides like glyphosate, “super weeds†also emerged with this resistance. This is due to the natural process of genetic selection, an evolutionary process where certain traits are advantageous and become more common than others.
“Depending on the type of GM microbes and the selection pressure put on the system to select for them, it is likely that the selection of super microbes will happen at a much faster rate than what we observed in super weed plants, which could lead to super soil microbes,†the researchers say. They continue: “Moreover, GMMs that harm soil biodiversity (by killing beneficial microbes) would be a significant threat because they would make the soil microbiome susceptible to invasion and disturbance. The question we, as a society, should be addressing is how we can support and stimulate the natural, incredible diversity of beneficial soil microbes instead of modifying them or stamping them out.â€
Insufficient Regulations
Genetic engineering, such as through the CRISPR-Cas9 technology, has allowed for the removal, addition, and/or alteration of DNA sequences that can then turn genes on or off within organisms. The review highlights: “Numerous scientific and popular articles envision CRISPR’s revolutionary role in solving a long list of human and societal ills. Increasing evidence, however, demonstrates that the process causes significant unpredictable changes in the genome, including additions, deletions, chromosomal shattering, and widespread mutations that do not occur naturally.â€
As this technology continues to advance, regulatory assessments are not advancing with it. “Rather than increasing regulatory requirements, numerous countries, including the U.S., Canada, UK, Japan, Australia, India, and others, have deregulated plant, animal, and/or microorganisms altered by gene- editing technology,†the authors write.
Currently within the U.S., there is no federal legislation that recognizes GMMs as a category, as well as no requirements for GMMs to undergo separate evaluations for potential environmental impacts. The responsibility of GMO regulation is divided among the Food and Drug Administration (FDA), the United States Department of Agriculture (USDA), and EPA, with “policies created prior to genetic engineering technology [that] are criticized as inadequate.â€
As the researchers note, “Most GMMs for commercial use fall under the purview of the EPA, which improperly regulates them as toxic controlled substances (industrial chemicals).†Under the Toxic Substances Control Act (TSCA), EPA only requires a 90-day notice from manufacturers using GMMs. “Regulating GMMs using methods designed for toxic chemicals is inappropriate and ignores the fact that these are biologically active organisms and critical to health and environment,†the authors state. Additionally, “Because EPA only regulates GMMs created for commercial use, most other GMMs, including those produced by formal and informal research, students, and home hobbyists, are unregulated and untracked.â€
For additional coverage from Beyond Pesticides on the role of genetic engineering (GE) in agriculture, see Consumer Choice and the Spread of Genetically Engineered Food, Court Nixes Scanning for Mandated Food Label Info, Allows GE Ingredients To Be Called “Bioengineeredâ€, and Government Report Pushes Genetically Engineered Crops, Despite Failure and Effective Alternatives.
Take Action
GMMs and GMOs in agriculture are not progress. They are part of the same failed, chemical-intensive farming system that already threatens pollinators like bees, pollutes water, and traps farmers on a costly chemical treadmill. We do not need genetically modified crops. What we do need is certified organic farming and traditional plant breeding—approaches that protect people and the planet by transitioning us away from toxic chemicals. Together, we can protect our food, support farmers and farmworkers, and build a healthier, more just food system for all. Take two actions: 1. Petition—Tell Food Companies to Reject GMO Wheat! and 2. Tell Congress to instruct USDA to prohibit HB4 wheat and instruct EPA to prohibit the use of glufosinate herbicides on wheat.
All unattributed positions and opinions in this piece are those of Beyond Pesticides.
Source:
Lerner, A. et al. (2026) Genetically Modified Microorganisms: Risks and Regulatory Considerations for Human and Environmental Health, Microorganisms. Available at: https://www.mdpi.com/2076-2607/14/2/467.
