25
Aug
Antibiotics and Neonicotinoid Insecticides Linked to Gut Microbiome Disruption and Childhood Diabetes
(Beyond Pesticides, August 25, 2022) A study published in World Journal of Pediatrics finds an association between antibiotic and neonicotinoid (neonic) exposure and onset of pediatric (childhood) type 1 diabetes (T1D) through effects on the gut microbiome. Individuals with type 1 diabetes are at higher risk of other autoimmune disorders, including thyroid and celiac disease. Ample evidence demonstrates environmental contaminants like pesticides and antibiotics negatively affect human mouth and gut microbes.
Through the gut biome, pesticide exposure can enhance or exacerbate the adverse effects of additional environmental toxicants on the body. Moreover, studies find low levels of pesticide exposure during pregnancy or childhood cause adverse health effects from metabolic/immune disorders to mental and physical disabilities. Children are particularly vulnerable to the impacts of pesticide exposure as their developing bodies cannot adequately combat exposure effects. Although studies show how chemical exposures affect overall human health, more research is now questioning how these toxic chemicals influence gut health and subsequent occurrence of diseases. In children, gut microbiome disruption, or gut dysbiosis, has significant associations with type 1 diabetes development, and disruption of gut microbiota plays a role in type 2 diabetes development. Over 11 percent (>37 million) of individuals in the U.S. have diabetes, and cases are growing by millions annually. With increasing rates of type 1 and 2 diabetes cases among the global population, studies like these highlight the importance of evaluating how chemical contaminants deregulate normal bodily function through microbiome changes.
There is a lack of understanding on the real-world effects of neonic and antibiotic exposure on gut microbiome changes akin to the onset of T1D. However, studies suggest the structure of gut microbiota in children can differ depending on the level of chemical exposure, leading to disparities in T1D risk. The study researchers highlight, “[M]ost existing studies on the health risks caused by antibiotics and pesticides tend to focus on the effect of high levels of exposure over short periods because relationships between long-term low-dose exposure and health risks are ambiguous and difficult to study. As a result, the mechanisms associated with their adverse effects on health remain unclear.”
The researchers evaluated antibiotic and neonic concentrations in the urine of 51 children newly diagnosed with T1D, comparing chemical exposure levels to those of healthy control children (without T1D). Mass spectrometry measured urine for concentrations of 28 antibiotics and 12 neonics, grouping children based on the type of chemical exposures. Furthermore, researchers compared gut microbiota in fecal matter to urine samples to determine a correlation between differences in gut microbiota and T1D onset.
The study detects antibiotics in 72.5 percent of children with T1D and 61.2 percent of healthy children, while neonics are present in 70.6 percent of children with T1D and 52.2 percent of healthy children. A child’s exposure to one type of antibiotic or two or more types of neonics increases the T1D risk 2.6 and 3.9-fold, respectively. Co-exposure to antibiotics and neonics has an association with T1D, increasing the risk 4.9-fold. Although antibiotic and neonic exposure has no impact on gut microbiota richness (number of species) and diversity (type of species), children unexposed to both antibiotics and neonics have a higher abundance of Lachnospiraceae (the core taxa of gut microbiota) than children exposed to antibiotics and neonicotinoids, alone or together.
The gut, also known as the “second brain,” shares similar structural and chemical parallels with the brain. Microbiota (i.e., groups of microorganisms, including bacteria, archaea, viruses, and fungi) in the gut play a crucial role in lifelong digestion, detoxification, immune and central nervous system regulation, and other bodily functions. Through the gut biome, pesticide exposure can enhance or exacerbate the adverse effects of additional environmental toxicants on the body. Since the gut microbiome shapes metabolism, it can mediate some toxic effects of environmental chemicals. However, prolonged exposure to various environmental contaminants induces a change in gut microbes, influencing adverse health outcomes. Since the gut microbiome shapes metabolism, it can mediate some toxic effects of environmental chemicals. However, prolonged exposure to various environmental contaminants can induce critical chemical changes in the gut microbes, influencing adverse health outcomes.
The impacts of pesticides on the human gut microbiome represent another pesticide assault on human health as the biome harbors between 10 and 100 trillion symbiotic microbes. The human gastrointestinal tract and its digestive processes (the “gut”) mediate the function of several systems. Dysfunction of the gut microbiome is associated with a host of diseases, including cardiovascular disease, some cancers, multiple sclerosis, diabetes, asthma, Crohn’s disease, Parkinson’s disease, and inflammatory bowel disease, as well as allergies, autism, depression, obesity, and other disorders or syndromes.
Over the past 20 years, neonicotinoids replaced four major chemical classes of insecticides in the global market (organophosphates, carbamates, phenyl-pyrazoles, and pyrethroids). These systemic agricultural pesticides are highly toxic, resembling nicotine and affect the central nervous system of insects, resulting in paralysis and death, even at low doses. Like other pesticides, neonics readily contaminate water and food resources as traditional water waste treatments typically fail to remove the chemical from tap water, and the systemic nature of neonics allows the chemical to accumulate within the product rather than externally. According to the Centers for Disease Control and Prevention (CDC), nearly half the U.S. population encounters at least one type of neonic daily, with children ages three to five having the highest exposure risk. Health impacts of exposure to neonics can include neurotoxicity, reproductive anomalies, hepatic and renal damage, and an increase in gene expression linked to hormone-dependent breast cancer. Additionally, researchers identified the role some neonicotinoids pay in the production of an enzyme (aromatase) that stimulates excess estrogen production, a known event in hormone-dependent cancer development.
Antibiotic exposure can allow more resilient bacteria to flourish in the gut microbiome and outcompete other beneficial bacteria. For instance, glyphosate, patented as an antibiotic by manufacturer Bayer/Monsanto, kills bacterial species beneficial to humans and incorporated in probiotics, yet allows harmful bacteria to persist, leading to resistance. Glyphosate’s mode of action targets and inactivates an enzyme in the “shikimate [metabolic] pathway” in plants. Although this pathway is not present in animal cells, it exists among bacterial species. However, antibiotic exposure can still impact other metabolic pathways in animals. Antibiotic resistance can trigger longer-lasting infections, higher medical expenses, the need for more expensive or hazardous medications, and the inability to treat life-threatening illnesses.
This study is the first to analyze a relationship between long-term, low-dose, daily exposure to antibiotic and neonic on gut microbiota. Children with T1D are more likely to encounter high levels of antibiotic and neonicotinoid exposure, altering bacteria in the gut. Although exposure to high levels of these compounds does not alter microbiota richness (number of species) and diversity (types of species) in the study, exposure to antibiotics and neonicotinoids is associated with small but critical changes to gut microbiota, specifically by disturbing specific taxa. Studies demonstrate gut dysbiosis-related diabetes has associations with decreased short-chain fatty acids and epithelial barrier disruption, allowing toxicants to induce systemic inflammation and insulin resistance. Therefore, children exposed to antibiotics, neonics, or both have an increased risk of T1D due to the lower abundance of Lachnospiraceae, a bacterium producing the short fatty acid chain (butyrate).
The study concludes, “[C]hildren with exposure to antibiotics and neonicotinoids had small but critical changes in gut microbiota, characterize[ed} by a lower abundance of butyrate-producing genera, especially Lachnospiraceae. Similar changes were also observed in T1D children, which were thought to be associated with the increase of autoimmune level. These findings suggest that exposure to high levels of antibiotics and pesticides in daily life might increase the risk of autoimmune diseases, such as T1D. Future work should focus on relationships between antibiotics and neonicotinoids exposure and the onset of autoimmune diseases in children, as well as the underlying mechanisms.”
Current risk assessment methods for pesticides are insufficient as assessment procedures fail to account fully for the sublethal effects of pesticides. With the globe currently going through the Holocene Extinction, Earth’s 6th mass extinction, with one million species of plants and animals at risk over the last four decades, action is needed to mitigate our anthropogenic impact on essential ecosystem organisms.
Pesticides themselves can possess the ability to disrupt metabolic function, especially for chronically exposed individuals (e.g., farmworkers) or during critical windows of vulnerability and development (e.g., childhood, pregnancy). Health officials identify Type 1 diabetes as one of the most common chronic childhood diseases, increasing among children younger than five years old. Therefore, it is essential to mitigate preventable exposure to disease-inducing pesticides. For more information on the effects of pesticide exposure on autoimmune and metabolic health, see Beyond Pesticides’ Pesticide-Induced Diseases Database pages on diabetes, immune system disorders, endocrine disruption, and more.
Replacing dietary exposure to food grown in chemical-intensive agriculture with organic consistently reduces pesticide levels in one’s body. Preventive practices like organic can eliminate exposure to toxic autoimmune disrupting pesticides, like neonics. There is an indication that maintaining lower levels of conventional, synthetic pesticides is likely to reduce the risk of developing chronic diseases like type 2 diabetes. In addition to positive impacts on the human microbiome, organically grown food (i.e., milk, meat, strawberries, tomatoes, and a range of other foods) contain a much more diverse bacterial community than their chemically grown counterparts. Organic agriculture represents a safer, healthier approach to crop production that does not necessitate toxic pesticide use. Beyond Pesticides encourages farmers to embrace and consumers to support regenerative, organic practices. A complement to buying organic is contacting various organic farming organizations to learn more about what you can do. Additionally, learn more about the hazards posed to children’s health through Beyond Pesticide’s Pesticide and You Journal article, “Children and Pesticides Don’t Mix.”
All unattributed positions and opinions in this piece are those of Beyond Pesticides.
Source: World Journal of Pediatrics
That’s really helpful…
August 26th, 2022 at 1:09 am