Scientists have discovered that the concentration of microplastics in human testicles is nearly three times higher than in those of dogs.
Additionally, new research reveals that 24 brain samples collected in early 2024 contained microplastics, making up approximately 0.5% of the sample’s weight. This information comes from a study reported by The Guardian.
Call for Stricter Measures
With mounting evidence showing that microplastics are accumulating in critical human organs, researchers are urging for stronger regulations to curb the increasing pollution caused by plastic waste.
Microplastics, defined by the U.S. National Oceanic and Atmospheric Administration (NOAA) as tiny plastic particles ranging from one nanometer to five millimeters, pose potential harm to marine life and ecosystems. These particles can originate from the breakdown of larger plastic debris into smaller pieces over time.
The vast amount of plastic waste in the environment has led to the widespread presence of microplastics, found everywhere from the peak of Mount Everest to the depths of the Mariana Trench.
Detected in Lungs, Placenta, Liver, and More
Recent research has uncovered the presence of microscopic plastic particles in various parts of the human body, including the lungs, placenta, testicles, liver, kidneys, joints, blood, and bone marrow.
One of the most alarming findings comes from a recent study conducted by the U.S. National Institutes of Health (NIH). This study, which is still under peer review, highlights the accumulation of microplastics in the brain. Researchers examined liver, kidney, and brain samples collected from autopsies and found traces of microplastics in all of them.
Of particular concern, the analysis of 91 brain samples revealed that the amount of microplastics was 10 to 20 times higher than in other organs. Lead author and toxicologist Matthew Campen from the University of New Mexico (UNM) called these findings “shocking.”
The Brain: A Highly Contaminated Organ
According to the study, microplastics in the 24 brain samples obtained in early 2024 made up, on average, 0.5% of their total weight. The research noted that the brain ranks among the most contaminated tissues in terms of microplastic presence.
The study also found that the amount of microplastics in 2024 samples was about 50% higher than those taken in 2016, demonstrating that the accumulation of microplastics in the human brain is increasing at the same rate as plastic pollution in the environment.
A particularly concerning aspect of this study is the potential link between microplastic contamination and dementia. Researchers examined 12 brain samples from individuals with dementia and Alzheimer’s disease and found that the concentration of microplastics was 10 times higher than in healthy brain samples. (At the time of publishing, the latest version of the study containing these findings was not yet available online.)
“I don’t know how much plastic our brains can absorb before it starts causing serious issues,” Campen warns.
Microplastic Levels in Human and Canine Testicles
In May, UNM researchers published another study, in which they analyzed 23 human testicles and 47 dog testicles. The canine testicles were obtained from animal castrations, while the human testicles came from autopsies performed on men aged 16 to 88 in 2016. After the legal storage period for the human samples expired, they were destroyed. The study, published in the journal Toxicological Sciences, found that the concentration of microplastics in human testicles was nearly three times higher than in dog testicles.
Global Efforts to Tackle Plastic Pollution
The United Nations Environment Assembly (UNEA) began working on a global treaty to end plastic pollution two years ago, and negotiations are ongoing.
“Nothing, from the ocean floor to the atmosphere, to the human brain, has remained untouched by microplastics,” concludes ecotoxicologist Bethanie Carney Almroth from the University of Gothenburg in Sweden.
