Human Gut Bacteria Can Gather Up PFAS ‘Forever Chemicals'
Bacteria commonly found in the human gut could potentially be used to gather up PFAS and carry them out as waste, researchers suggest in a study published this week in Nature Microbiology.
'I think this research provides us a little glimmer of hope that it's not all doom and gloom' when it comes to the PFAS problem, says study co-author Kiran Patil, a molecular biologist at the University of Cambridge. 'Maybe our bacteria—that have been our companions for thousands of years—may already be helping us do something about it.'
On supporting science journalism
subscribing. By purchasing a subscription you are helping to ensure the future of impactful stories about the discoveries and ideas shaping our world today.
The team first tested how PFAS and other pollutants interacted with dozens of bacterial strains from the human gut and noticed that nine of them accumulated certain PFAS chemicals very effectively. When grown in laboratory conditions, these bacteria sopped up anywhere from 25 to 74 percent of the PFAS chemicals they were exposed to within 24 hours. The researchers suggest those particular strains could potentially bind to PFAS in the body and carry them out of the system.
Previous work had shown that bacteria from contaminated soils can bind to PFAS. But those bacteria were exposed to much higher levels of the chemicals and had a relatively low capacity to sequester them—'so we had no reason to believe that gut bacteria would be anything special,' Patil says.
Many researchers had assumed that PFAS molecules would cling to a bacterium's outer membrane rather than getting inside it, Patil says. Because the bacteria in the study were gathering more PFAS than could feasibly fit on their membrane, however, the team thought the chemicals must have actually entered the organisms. To confirm this, Patil and his colleagues used an imaging technique in which they rapidly froze the bacteria, then fired tiny beams of charged particles at them and analyzed what flew out. The researchers detected fluorine molecules—a telltale sign of PFAS—emerging from the bacteria.
To find out whether bacteria would still collect PFAS chemicals inside a larger organism, the team used mice raised to lack a microbiome of their own and colonized the animals' gut with several human microbiome bacteria that were shown to absorb PFAS. After exposing the mice to various levels of a PFAS chemical, the researchers measured the amount of PFAS in the animals' feces and found that mice with PFAS-collecting bacteria excreted more of the toxic chemicals than those without the microorganisms did.
This study shows just how deeply PFAS penetrate a body and its systems, says environmental epidemiologist Jesse Goodrich, who was not involved in the work. 'It is another piece in the puzzle that shows how PFAS can impact human health.'
Applying the latest findings to humans would require more research. The team is now planning a clinical trial to test whether probiotics containing such bacteria could potentially supplement the human microbiome and decrease PFAS in our own species' gut. But the researchers note that such a trial would have far more variable factors than a highly controlled study in mice with lab-designed microbiomes. 'There's a huge variation in how the composition of the microbiome is set up within humans,' says the new study's lead author Anna Lindell, a toxicologist at the University of Cambridge.
Further research could also observe the naturally occurring levels of these bacterial strains in people within the same community and measure the amount of PFAS in their bodies, Patil says. Such a study would help to clarify whether these bacteria lead to less PFAS in the human gut—or even in other parts of the body.
Supplementing the body's natural bacteria to manage PFAS absorption is 'interesting and has potential,' Goodrich says. 'But ultimately, the best way to protect health is to prevent exposure in the first place.'
Try Our AI Features
Explore what Daily8 AI can do for you:
Comments
No comments yet...
Related Articles
Scientific American
2 days ago
- Scientific American
Human Gut Bacteria Can Gather Up PFAS ‘Forever Chemicals'
Lurking in our nonstick pans, our rain jackets and even our drinking water are toxic compounds known as perfluoroalkyl and polyfluoroalkyl substances (PFAS), also called 'forever chemicals.' They can take hundreds of years to break down in the environment and are increasingly being detected in human blood and bodily tissues—where, research suggests, they can lead to several cancers and reproductive disorders, as well as thyroid disease and a weakened immune system. Scientists have been scrambling for ways to remove PFAS from our surroundings before they reach human bodies. But one team may now have found a way to tackle them afterward. Bacteria commonly found in the human gut could potentially be used to gather up PFAS and carry them out as waste, researchers suggest in a study published this week in Nature Microbiology. 'I think this research provides us a little glimmer of hope that it's not all doom and gloom' when it comes to the PFAS problem, says study co-author Kiran Patil, a molecular biologist at the University of Cambridge. 'Maybe our bacteria—that have been our companions for thousands of years—may already be helping us do something about it.' On supporting science journalism subscribing. By purchasing a subscription you are helping to ensure the future of impactful stories about the discoveries and ideas shaping our world today. The team first tested how PFAS and other pollutants interacted with dozens of bacterial strains from the human gut and noticed that nine of them accumulated certain PFAS chemicals very effectively. When grown in laboratory conditions, these bacteria sopped up anywhere from 25 to 74 percent of the PFAS chemicals they were exposed to within 24 hours. The researchers suggest those particular strains could potentially bind to PFAS in the body and carry them out of the system. Previous work had shown that bacteria from contaminated soils can bind to PFAS. But those bacteria were exposed to much higher levels of the chemicals and had a relatively low capacity to sequester them—'so we had no reason to believe that gut bacteria would be anything special,' Patil says. Many researchers had assumed that PFAS molecules would cling to a bacterium's outer membrane rather than getting inside it, Patil says. Because the bacteria in the study were gathering more PFAS than could feasibly fit on their membrane, however, the team thought the chemicals must have actually entered the organisms. To confirm this, Patil and his colleagues used an imaging technique in which they rapidly froze the bacteria, then fired tiny beams of charged particles at them and analyzed what flew out. The researchers detected fluorine molecules—a telltale sign of PFAS—emerging from the bacteria. To find out whether bacteria would still collect PFAS chemicals inside a larger organism, the team used mice raised to lack a microbiome of their own and colonized the animals' gut with several human microbiome bacteria that were shown to absorb PFAS. After exposing the mice to various levels of a PFAS chemical, the researchers measured the amount of PFAS in the animals' feces and found that mice with PFAS-collecting bacteria excreted more of the toxic chemicals than those without the microorganisms did. This study shows just how deeply PFAS penetrate a body and its systems, says environmental epidemiologist Jesse Goodrich, who was not involved in the work. 'It is another piece in the puzzle that shows how PFAS can impact human health.' Applying the latest findings to humans would require more research. The team is now planning a clinical trial to test whether probiotics containing such bacteria could potentially supplement the human microbiome and decrease PFAS in our own species' gut. But the researchers note that such a trial would have far more variable factors than a highly controlled study in mice with lab-designed microbiomes. 'There's a huge variation in how the composition of the microbiome is set up within humans,' says the new study's lead author Anna Lindell, a toxicologist at the University of Cambridge. Further research could also observe the naturally occurring levels of these bacterial strains in people within the same community and measure the amount of PFAS in their bodies, Patil says. Such a study would help to clarify whether these bacteria lead to less PFAS in the human gut—or even in other parts of the body. Supplementing the body's natural bacteria to manage PFAS absorption is 'interesting and has potential,' Goodrich says. 'But ultimately, the best way to protect health is to prevent exposure in the first place.'
Yahoo
2 days ago
- Yahoo
Our gut bacteria can absorb and remove toxic 'forever chemicals' — at least in lab mice
When you buy through links on our articles, Future and its syndication partners may earn a commission. Researchers have identified gut bacteria that can absorb toxic "forever chemicals" in lab mice, according to a new study, potentially offering up a way to control PFAS levels in humans. PFAS, or perfluoroalkyl and polyfluoroalkyl substances, are synthetic chemicals used in a variety of products, from non-stick cooking pans to cosmetics. These substances are often nicknamed "forever chemicals" because they have strong chemical bonds that don't easily break down in nature and, in some cases, stick around for thousands of years. As a result, these chemicals pose a major pollution concern, both in our environment and in our own bodies. Our drinking water and agricultural systems are already contaminated with PFAS to some degree, and as some of these chemicals can be absorbed through the skin and into our blood, there's no keeping them out of our bodies. Scientists are still untangling the health implications of PFAS, but exposure has been linked to various potential harms, including an increased risk of some cancers and disruptions to our immune system. However, our bodies may also have a way of protecting themselves from these chemicals. The new study, published Tuesday (July 1) in the journal Nature Microbiology, investigated how human gut bacteria interacted with PFAS and found that nine species could effectively fend off the chemicals, at least in lab mice. The bacteria absorbed a good chunk of common PFAS that the mice were exposed to, which was then excreted in the mice's feces. While there's a lot more work to be done, these findings suggest that we may be able to employ some bacterial species to control forever chemicals. "The reality is that PFAS are already in the environment and in our bodies, and we need to try and mitigate their impact on our health now," study co-author Indra Roux, a researcher in the Medical Research Council (MRC) Toxicology Unit at the University of Cambridge, said in a statement. "We haven't found a way to destroy PFAS, but our findings open the possibility of developing ways to get them out of our bodies where they do the most harm." Related: How worried should we be about PFAS, the 'forever chemicals'? PFAS resist water, oil and heat, making them useful in many different products. Today, there are thousands of different chemicals under the PFAS umbrella. While they are being phased out of some industries, like food packaging, many already exist in the environment and aren't going anywhere anytime soon. To explore how gut bacteria interact with PFAS, the researchers first identified nine bacterial species that could absorb these chemicals and then gave those species to lab mice. The mice were then exposed to PFAS, including the common perfluorooctanoic acid (PFOA) and perfluorononanoic acid (PFNA). The bacteria absorbed between 25% and 74% of PFNA and 23% to 58% of PFOA, according to the study. Accumulated PFAS didn't seem to affect the bacteria much. The PFAS aggregated (grouped together) in dense clusters within the bacteria, which appeared to minimize their impact on vital cell processes, according to the study. "We found that certain species of human gut bacteria have a remarkably high capacity to soak up PFAS from their environment at a range of concentrations, and store these in clumps inside their cells," senior study author Kiran Patil, an investigator within the University of Cambridge's MRC Toxicology Unit, said in the statement. "Due to aggregation of PFAS in these clumps, the bacteria themselves seem protected from the toxic effects." RELATED STORIES —PFAS 'forever chemicals' to officially be removed from food packaging, FDA says —Scientists find a simple way to destroy 'forever chemicals' — by beheading them —PFAS can absorb through the skin, potentially threatening our health, study finds The researchers noted in the study that their experiments involved giving mice a one-time dosage of PFAS, while humans — and other animals — typically experience low but chronic exposure to the chemicals. Lawrence Wackett, a professor of biochemistry at the University of Minnesota Twin Cities who wasn't involved in the study, told Live Science in an email that the research was "particularly interesting" in light of another study published June 13 in the journal PNAS, which found that human gut microbial enzymes can break down carbon–fluorine bonds — the strong bonds present in PFAS. "Taken together, there might be both sequestration and degradation of certain fluorinated compounds in the human gut," Wackett said.
Yahoo
2 days ago
- Yahoo
Gut Bacteria Found to Soak Up Toxic Forever Chemicals
Perfluoroalkyl and polyfluoroalkyl substances (PFAS) have the nickname 'forever chemicals' thanks to their persistence in the environment. While a handful of bacteria are known to mop up these insidious compounds, it's unclear whether any of our own microflora hide such a talent. A new study by an international team of researchers has shown how several species of human gut bacteria can absorb and store PFAS. Potentially, boosting these types of bacteria in our bodies could stop the chemicals from negatively impacting our health. "We found that certain species of human gut bacteria have a remarkably high capacity to soak up PFAS from their environment at a range of concentrations, and store these in clumps inside their cells," says Kiran Patil, a molecular biologist from the University of Cambridge in the UK. "Due to aggregation of PFAS in these clumps, the bacteria themselves seem protected from the toxic effects." Related: Through detailed lab tests, the researchers found a total of 38 different gut bacterial strains able to absorb forever chemicals at a variety of concentrations, with the fiber-degrading bacterium Bacteroides uniformis one of the best at the job. In experiments with Escherichia coli, the team also discovered certain mechanisms that could make bacteria more or less effective at taking on board PFAS – something that will be useful if this absorption can be bioengineered in the future. The researchers found that PFAS were effectively locked away in the bacteria that could handle the chemicals, the bacteria clustering together in a way that reduces their surface area and possibly protects the microorganisms from being harmed themselves. Further tests on mice with nine of these bacteria species implanted in their guts showed that the microbes were able to quickly absorb PFAS, which was excreted from the mice through their feces. As levels of forever chemicals increased, the microbes worked harder at soaking them up. "The reality is that PFAS are already in the environment and in our bodies, and we need to try and mitigate their impact on our health now," says molecular biologist Indra Roux from the University of Cambridge. "We haven't found a way to destroy PFAS, but our findings open the possibility of developing ways to get them out of our bodies where they do the most harm." PFAS are found in everything from cosmetics to drinking water to food packaging, and have become embedded in so many manufacturing processes that it would now be almost impossible to avoid them completely. What's less clear is the harm they might be doing to our bodies, though they've already been linked to a number of health issues – including kidney damage. The bacteria's ability to remove PFAS from human bodies remains to be seen. It is possible, the researchers say, that probiotic dietary supplements may be developed to boost the right mix of gut microbes and help safely clear out PFAS from our systems. "Given the scale of the problem of PFAS 'forever chemicals', particularly their effects on human health, it's concerning that so little is being done about removing these from our bodies," says Patil. The research has been published in Nature Microbiology. Gene Therapy Can Restore Hearing in Adults, First-of-Its-Kind Trial Shows Cheese May Actually Fuel Nightmares, Surprising Study Confirms New Weight-Loss Drugs Under Scrutiny Amid Pancreas Concerns
