Microplastics found in every human testicle tested in new study

Microplastics have been detected in every human testicle examined in a new study, raising questions about the possible impact on health and fertility.

The research, led by the University of New Mexico and published in the journal Toxicological Sciences, looked at testicular tissue taken from dogs and humans. The scientists tested 23 human and 47 dog testes. 

Microplastics are created when plastic is exposed to ultraviolet radiation in sunlight and degrades in landfills, and cause pollution in the environment.

These very small pieces of plastic were found in every sample tested, but for humans the number was almost three times higher – 329.44 micrograms per gram – than in canines (122.63mg/g). 

The most prevalent type found in both humans and dogs was polyethylene (PE), which is used to make plastic bags and bottles.

PVC found to reduce sperm count in dogs

The study also found higher levels of polyvinyl chloride (PVC) in dog tissue correlated with a lower sperm count. There was no correlation with tissue concentration of PE. 

PVC is one of the most widely used products in the world, often found in pipes and medical devices.

Finding microplastics in human testicles has raised concern about how the tiny fragments could affect male fertility. 

‘I was surprised’

Environmental health scientist Xiaozhong Yu, from the University of New Mexico, said of the canine results: “The plastic makes a difference – what type of plastic might be correlated with potential function. PVC can release a lot of chemicals that interfere with spermatogenesis and it contains chemicals that cause endocrine disruption. 

“At the beginning, I doubted whether microplastics could penetrate the reproductive system. When I first received the results for dogs, I was surprised. I was even more surprised when I received the results for humans.”

Don’t panic: there are still a lot of unknowns

But, he added, there are still “a lot of unknowns”, so there’s no reason to panic.

“We don’t want to scare people. We want to scientifically provide the data and make people aware there are a lot of microplastics.

“We can make our own choices to better avoid exposures, change our lifestyle and change our behaviour.”