Gut Microbiome Affected by Toxic Chemicals in Products, Environment, Food

Thanks to recent scientific and medical research studies, scientists, practitioners and the general public have begun to become aware of how gut microbiome impacts human health and well-being. The reason this is important:  The microbes that inhabit our bodies are influenced by what we eat, drink, breathe and absorb through our skin, and most of us are chronically exposed to natural and human-made environmental contaminants.  In this study, scientists reviewed the research linking dozens of chemicals present in our personal care products, home care products, general environment and our food to changes in the gut microbiome and associated health challenges.

Study overview

Researchers examined studies focusing on compounds used in manufacturing consumer goods, including the bisphenols found in plastic food packaging, and phthalates, which are used in everything from vinyl flooring to plastic films. It also describes the science associated with exposure to persistent organic pollutants and heavy metals. POPs include chemicals like PCBs; perfluorochemicals, which are used in nonstick cookware and food packaging; flame retardants known as polybrominated diphenyl ethers; and pesticides and herbicides.


BPA Phthlates chemical exposure obesity diabetes

We are regularly exposed to toxic chemicals that can affect our health


“Chemicals such as bisphenols, phthalates and some pesticides, persistent organic pollutants and heavy metals can alter hormone metabolism and are associated with adverse health outcomes.”

-Dr. Jodi Flaws, researcher, professor of comparative biosciences, University of Illinois

The negative health effects linked to these chemicals include reproductive and developmental defects, Type 2 diabetes, cardiovascular dysfunction, liver disease, obesity, thyroid disorders and poor immune function.  The present examination focused on how these toxic chemicals affects gut microbiome…


Environmental chemicals-bpa montage

BPA and BPS in Food / Drinks Packaging

Studies have found that exposure to bisphenols, which are detectable in the urine of more than 90% of adults in the United States, increases levels of Methanobrevibacter bacteria in the male gut. These microbes have been shown — in humans and in mice — to boost their host’s ability to extract more energy from food.

This raises a strong possibility that BPA-induced weight gain is caused at least partially by BPA-induced changes in the gut microbiome.


phthalate douche

Phthalates in Personal Care Products/ Home Care Products / Food Packaging

Phthalates are plasticizers and stabilizers that easily leach into foods. Eating phthalate-contaminated foods is the primary route of exposure in humans. Like bisphenols, phthalates are endocrine disruptors, meaning that they interfere with normal hormone-signaling in the body.

High phthalate exposure in human newborns is associated with changes in the gut microbiome and altered immune responses to vaccination. In mice, exposure to phthalates during puberty appears to inhibit the microbial synthesis of butyrate, a metabolite that is essential for intestinal health, immune regulation and neurological function.

food chemicals-PCBs IN FOOD


Persistent organic pollutants are oily organic chemicals that can persist in the environment for years or decades.

Studies have found that exposure to PCBs is associated with microbial shifts in the gut and increased gut permeability, intestinal inflammation and cognitive problems. Once used as coolants, PCBs were banned in the U.S. in 1978 but persist in the environment.

PFC food containers



PFCs in nonstick cookware, food packaging and stain-resistant clothing, furniture, carpets

Perfluorochemicals are used in nonstick cookware, food packaging and stain-resistant carpets. One study linked PFCs to changes in the gut microbiome and impaired lipid metabolism in female — but not male — fish and their offspring. The microbiome shifts persisted in the offspring, and the young fish suffered higher mortality than those whose mothers were not exposed to PFCs.

roundup weedkiller concentrate

Pesticide Chlorpyrifos and Herbicide Glyphosate [RoundUp Weed Killer]

Studies have found that exposure to glyphosate herbicides alters the bacterial makeup of the gut microbiome in cattle, rodents and honey bees. It increased anxious and depressive symptoms in mice and was associated with an increase in pathogenic bacteria in cattle. The pesticide chlorpyrifos affects microbial populations in male rodents and fish exposed during development and adulthood, and also causes inflammation and oxidative stress in the gut.

The Takeaway

“All of these data together suggest that exposure to many of these environmental chemicals during various stages of life can alter the gut microbiome in ways that influence health. The pathologies associated with altered microbiomes after exposure to environmental chemicals include immune dysfunction, altered carbohydrate and lipid metabolism, and neurological and behavioral impairments. We are also seeing that these effects highly depend on an individual’s sex and age.”

-Karen Chiu, researcher


Journal Reference: Wenyan Mei, Jodi A Flaws, Romana A Nowak, Genoa Warner, Karen Chiu. The Impact of Environmental Chemicals on the Gut Microbiome. Toxicological Sciences, 2020; DOI: 10.1093/toxsci/kfaa065










Posted by: AS/Dr. Scott