There is nothing really surprising in the fact that micro- and nanoplastic particles have been found in human penises, believes a Quebec expert who warns that their presence elsewhere in the reproductive system is much more worrying.
“When a man has an erection, the corpora cavernosa fill with blood,” said Professor Daniel G. Cyr, Chair of Research in Reproductive Toxicology at the Armand-Frappier Santé Biotechnologie Centre of the Institut national de la recherche scientifique. “And since we find micro and nanoplastic particles in the blood, it’s not surprising that they accumulate there. The question is whether it has a harmful effect, and that’s much less clear.” Scientists find micro and nanoplastic particles almost everywhere they decide to look in the human body, but their impact on health remains poorly understood and needs to be studied more thoroughly.
For example, American researchers recently reported in the medical journal IJIR: Your Sexual Medicine Journal that they had detected particles in four of five penile tissue samples taken from men who had undergone surgery for significant erectile dysfunction. Seven different types of microplastics were detected, with polyethylene terephthalate and polypropylene being the most common. Both substances are used in a multitude of everyday objects. “The identification by this study of the presence of microplastic particles in penile tissue raises compelling questions about their potential influence on erectile function, given their known association with localized adverse effects on tissues,” the authors write. Other recently published studies have also found the presence of micro- and nanoplastic particles in the testes and in semen.
Sperm count
Sperm counts have been plummeting for decades, without anyone really understanding why, and 40% of cases of low counts remain unexplained. However, several studies have pointed the finger in the direction of chemical pollution. “The most worrying thing about plastics is that they will often bind other things, other pollutants, heavy metals, viruses, bacteria,” said Mr. Cyr. I think the spread of these viruses or bacteria is much more worrying.” We are starting to have more and more scientific literature, he added, which demonstrates that microplastics can have harmful effects on the testicle and on the formation of spermatozoa. That being said, we are not yet able to draw any conclusions regarding the penis, he stressed: “At most, it tells us that there is a problem.”
Especially since the levels of microplastics that have been detected in the penis are not that high, said Mr. Cyr. On the other hand, the levels that were measured, in other work, in the testicle were higher than those that had been measured in the placenta. “The penis is a muscle,” added Mr. Cyr. It is not the same thing as the germ cells which will form sperm and which are much more sensitive. Recent scientific data even raises the hypothesis that microplastics can be transported to organs by the cells themselves, whereas until now it was believed that the particles took advantage of inflammation to overcome the normal protective barriers of the organism. This would mean that the barriers that protect, for example, the brain or testicles will be unable to prevent the entry of microplastics even if they are intact, since the particles are carried by cells.
“In terms of the penis and erections, microplastics are one thing, but what microplastics carry is something else,” Cyr said. “It’s not just the toxicity of the plastic itself: it’s the toxicity of what it can bring with it. And in the future, I think that’s what’s going to be the key to understanding the toxicity of microplastics.” Micro- and nanoplastic particles come in particular from the degradation of larger plastic items. Microplastics range in size from one micrometer (one millionth of a meter) to about five millimeters. Nanoplastics are measured in billionths of a meter. For comparison, the circumference of a human hair is about 70 micrometers. These particles are so tiny that they can enter the bloodstream (for example, by crossing the intestinal barrier) and go directly to the organs. In addition to possibly having carcinogenic properties, they could be a source of oxidative stress and mimic the action of certain hormones.
Humans are exposed to micro- and nanoplastic particles in outdoor and indoor environments through food, beverage consumption, air, and many other sources, including cosmetics and personal care products.
Caption and photo credit: (AP Photo/Ted S. Warren, File)
