Artificial chemicals, such as pesticides and polymers, are integrated into nearly every aspect of daily life and don’t halt entering our bodies through food, water, and general environmental exposure. While designed to interact only with their specific target, like insects or fungi, scientists wonder: could they still impact our health?
In a recent Nature Microbiology study, researchers from the University of Cambridge analyzed synthetic chemicals’ impact on our gut microbiome and found that 168 of the 1076 compounds they tested suppressed the growth of selected beneficial human gut bacteria. Besides hindering microbes from flourishing, some bacterial strains have even developed antibiotic resistance.
Scientists hope that their initial findings, in combination with their machine learning tool to predict the antibacterial activity of artificial chemicals, will inspire further research and inform safety assessments of novel chemicals on human health.
Read More: What to Do — and Not Do — to Keep Your Gut Microbiome Healthy
Synthetic Chemicals May Interact with Gut Microbes
Today’s agriculture and industry heavily rely on artificial chemicals to carry their productions, with a toll on the environment and our health that still needs to be determined. Pesticides pollution in particular alarms global food safety authorities as they contaminate our foods and waters, entering our bodies easily.
As soon as synthetic chemicals enter our guts, they will encounter our vast internal microbiome, which are crucial contributors to our overall health. Despite many chemicals observed to interact with non-target organisms, including soil bacteria, standard chemical safety testing does not include the human gut microbiome.
Developers state that novel chemicals are specifically designed to only interact with their target, such as insecticides specifically disrupting an insect's nervous system, growth, or metabolism. However, concerns remain regarding their broader toxicity range and indirect impact on humans by disrupting a balanced gut microbiome.
Chemicals Halt Bacterial Growth and Induce Antibiotic Resistance
Because it’s currently not feasible to measure the exact impact of single chemicals on specific gut bacteria in a living organism, the Cambridge team tested a range of common synthetic chemicals on 22 bacteria species that comprise a healthy microbiome in vitro.
They discovered that 168 of those chemicals halted bacterial growth, with fungicides and industrial chemicals showing the largest impact.
“We were surprised that some of these chemicals had such strong effects. For example, many industrial chemicals like flame retardants and plasticizers — that we are regularly in contact with — weren’t thought to affect living organisms at all, but they do,” said the study's first author, Indra Roux, researcher at the University of Cambridge’s MRC Toxicology Unit, in a press release. Surprisingly, most of the identified chemicals aren’t listed as antimicrobial.
Another concern was the development of antibiotic resistance. As a defense mechanism against the exposure of chemical pollutants, some bacteria mutated into strains showing resistance to ciprofloxacin, a common broad-spectrum antibiotic.
Wash Your Fruits and Vegetables
Based on the gathered data, the researchers were able to train a machine learning tool “to predict the effects of new chemicals, with the aim of moving to a future where new chemicals are safe by design,” explained senior study author Kiran Patil, professor at the University of Cambridge’s MRC Toxicology Unit, in the statement.
The research team hopes that future safety assessments for novel chemicals also take our gut microbiome into consideration, since their exposure through daily food and water intake is constant. To further back up their findings and see the direct influence on our health, studies on whole-body exposure by collecting real-world exposure data are the next step.
For now, avoiding exposure is key. In case of produce, we should stick to washing our fruits and vegetables before consuming them, they recommend, as well as avoiding pesticides in our own homes as much as we can.
This article is not offering medical advice and should be used for informational purposes only.
Read More: Things to Know Before Spraying Pesticides On Your Garden
Article Sources
Our writers at Discovermagazine.com use peer-reviewed studies and high-quality sources for our articles, and our editors review for scientific accuracy and editorial standards. Review the sources used below for this article:
- This article references information from a new study that was published in Nature Microbiology: Industrial and agricultural chemicals exhibit antimicrobial activity against human gut bacteria in vitro
