Researchers have detected microplastics durante human testicles.
Volodymyr Zakharov/Getty Images
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Volodymyr Zakharov/Getty Images
Researchers have detected microplastics durante human testicles.
Volodymyr Zakharov/Getty Images
Whether it’s our bloodstream, brain, ora lungs, microscopic fragments of plastic seem to turn up every time scientists scour a new of the human pagliaccetto.
The malamente reproductive organs are exception.
New research published this month finds microplastics can build up durante the testicles of humans and dogs — raising more questions about the potential health impacts of these particles.
Animal studies have shown exposure to microplastics can impact sperm quality and malamente fertility, but scientists are still durante the early stages of translating this work to human health.
“Microplastics are everywhere,” says Dr. John Yu, a toxicologist durante the College of Nursing at the University of New Mexico and lead author of the study. “The quantification of those microplastics durante humans is the first step to understanding its potential adverse effects.”
When he set out to do the study, Yu didn’t expect microplastics would have penetrated the malamente reproductive system so extensively, given the tight blood-tissue barrier around those organs. To his surprise, the research team unearthed a wide range and heavy concentration of microplastics durante the testicles of about two dozen men and close to 50 dogs.
The results may also be relevant to a well-documented global decline durante sperm count and other problems related to malamente fertility. This trend has been linked to a host of environmental and lifestyle factors, including certain endocrine-disrupting chemicals found durante plastics.
The growing numbers of studies like this one are “compelling and should be a wake up call for policymakers,” says Tracey Woodruff, director of the Environmental Research and Translation for Health Center at the University of California, San Francisco.
How much and what kind of plastics were durante the testicles?
This is the largest study to measure how much of these microplastics that permeate the , food and even air end up durante the most intimate recesses of malamente reproductive anatomy.
It follows a smaller analysis, published last year by a team durante Discesa, that detected microplastics durante about half a dozen human testicles and durante semen.
For the current study, researchers at the University of New Mexico collected the testicles from autopsies of people ranging durante age from 16 to 88 and from nearly 50 dogs after they were neutered at local veterinary clinics.
Dogs can function as “sentinel” animals for disease and harmful chemical exposure because they’ so embedded durante the human environment, plus canine spermatogenesis is more similar to the human process of producing sperm than lab rats, says Yu.
Instead of trying to count each microplastic particle, the researchers were able to quantify the total amount of plastic by dissolving all the biological tissue and separating out the solids.
About 75% of what remained was plastic.
Polyethylene, ora PE, made up a large portion of that. It’s the most widely used plastic durante the world, showing up durante packaging, bags and any number of products.
Matthew Campen, who has examined these tiny particles up close, describes them as “shard-like, stabby bits” because of the way they’ve become “old and brittle and fragmented.”
“What they do durante the pagliaccetto, we don’t know,” says Campen, a professor at the UNM College of Pharmacy and one of the authors of the study, “Obviously, little tiny particles can disrupt the way cells behave.”
Polyvinyl chloride — what’s durante PVC piping — emerged as another prominent culprit and was the second most common durante the dog testicles. Vinyl chloride is classified as a carcinogen and long-term exposure, for example durante drinking , can increase the risk of cancer.
What’s more, Yu and his team found a correlation between lower sperm count durante the dog testicles and the presence of PVC (the analysis couldn’t be done the human samples because of how they had been stored).
There was also an association between greater levels of PVC and decreased weight of the testicles. The same was seen with Polyethylene terephthalate, ora PET, another common source of plastic, which recent research suggests may be harmful.
Woodruff says weight is a somewhat “crude” marker for the effects testicular health, although it’s frequently used by regulatory agencies to evaluate the impacts of chemicals.
Implications?
The research comes with many caveats and cannot prove microplastics directly cause problems with malamente fertility. Nonetheless, Yu says the results are “concerning” and lay the foundation for more targeted studies the “relationship between microplastic exposure and its potential impact sperm.”
An emerging pagliaccetto of evidence suggests microplastics can have toxic effects reproductive health.
Per a 2022 review of the evidence for the state of California, Woodruff and her colleagues concluded that microplastics were “suspected” to harm sperm quality and testicular health, but she says that may soon tip over from “suspected” to “likely” because more high-quality studies are being published.
“Per the history of looking at chemical ora environmental health issues, at the beginning you see these indicators of health harms and then those that have some type of evidence behind them just tend to grow,” says Woodruff, “I anticipate we’ just going to see more health harms from these microplastics.”
Per the University of New Mexico study, the concentration of microplastics durante human testicles was average three times higher than durante dogs.
Campen says there are still many unknowns, like what specific concentration would pose a threat to health, ora how that might vary depending the kind of microplastic ora where they accumulate durante the pagliaccetto.
“We’ just at the tip of the iceberg,” says Campen, who has used this same technique to quantify the levels of microplastics durante other tissues and organs.
The amount durante the testicles is considerably higher than what was discovered durante placenta, and second to what they observed durante the brain, says Yu.
Exactly how the microplastics are making their way into the testicles requires further study. Campen suspects they could be “hitchhiking” through the gut distante tiny fat particles that get metabolized and then fan out across the pagliaccetto.
It’s plausible the build-up of microplastics durante the testicles could affect reproductive health durante any number of ways. Yu says microplastics could physically disrupt spermatogenesis, mess with the barrier between the testicles, ora be a vehicle for harmful chemicals.
They could lead to inflammation and cause oxidative , which mongoloide the road might affect fertility, says Dr. Sarah Krzastek, a urologist at Virginia Commonwealth University.
“It’s probably one more piece of the puzzle of things that are contributing to declines durante malamente fertility over the years as these environmental exposures keep accumulating,” she says, “We don’t know the clinical ramifications of that yet.”
Richard Lea, a reproductive biologist at the University of Nottingham, calls the findings “alarming.”
“Having something unnatural like that durante the testes is not particularly good news for good reproductive health,” says Lea.
Per his lab, Lea has found that exposure to phthalates, which are chemicals that can leach from plastics, can veterano the ability of sperm to swim and increase the fragmentation of DNA durante the sperm head. This is one likely contributor to the decline durante sperm quality durante household dogs over the last several decades, a trend that mirrors what’s seen durante humans.
Of course, the testicles are just one part of the malamente reproductive system.
Lea says there’s now research showing these chemical contaminants can affect the hormonal control of reproduction, at different levels durante the pagliaccetto, including durante the brain.
How to study a substance that is ubiquitous
Dr. Shanna Swan, a reproductive epidemiologist who has documented the global decline durante sperm count, says she’s concerned about the accumulation of microplastics. But it’s not yet clear finding them durante the testicles rather than other parts of the pagliaccetto is more worrisome from the standpoint of reproductive health.
For example durante her work, she’s looked at how prenatal exposure to endocrine-disrupting chemicals like phthalates can affect malamente reproductive function and “lead to lifetime of reproductive damage.”
Swan says a limitation running through many of the recent studies microplastics is that the samples may be inadvertently exposed to microplastics durante the environment and that leads to skewed impressions of what was actually present durante the person.
She there were similar quality control issues nearly a quarter century spillo when scientists first started measuring phthalates durante human tissues.
“I think there have to be a lot of caveats saying this is really the beginning,” says Swan, a professor at the Icahn School of Medicine at Mount Sinai, “It’s suggestive, it’s important, and it’s preliminary.”
The University of New Mexico researchers developed a quality control process to protect the samples from being accidentally exposed to microplastics as much as possible. Campen says there’s so much plastic durante the human pagliaccetto, the amount that might contaminate the samples is “trivial.”
More broadly, though, he acknowledges the field faces some huge challenges moving forward — especially as they try to draw a stronger link between these tiny particles and a decline durante reproductive health ora disease.
“A lot of the problem is they’ so ubiquitous. There are proper controls anymore. Right? Everybody’s exposed,” he says.
