Microplastics found in human penile tissue cause concern over fertility
Plastic pieces in frozen water. PHOTO | OLIVIER MORIN | AFP
What you need to know:
- Global plastic production reached about 489 million tonnes in 2023 and is forecasted to reach 1.2 billion tonnes in 2060.
- When these plastics degrade chemically or wear down physically into tinier pieces, they form microplastics.
Scientists have, for the first time, detected the presence of microplastics in men’s penile tissue, sparking concerns about their prevalence and potential health risks.
Data from ScienceDirect, a medical journal, states that global plastic production reached about 489 million tonnes in 2023 and is forecasted to reach 1.2 billion tonnes in 2060. When these plastics degrade chemically or wear down physically into tinier pieces, they form microplastics.
Microplastic fragments vary in size from less than five millimetres to as small as one micrometre. They result from plastic manufacturing, degradation, airborne and industrial sources in the environment.
The scientists from the University of Miami arrived at the conclusion following a study they conducted between August and September 2023. During the study, the researchers collected penile tissue from men who were undergoing surgery for erectile dysfunction and performed a chemical imaging analysis. They discovered that four out of five men had seven different types of microplastics in their penile tissue.
“The study found that microplastics, tiny plastic particles less than five mm in size, were present in the penile tissue of men who underwent surgery for erectile dysfunction. These microplastics were detected in 80 per cent of the samples, with the most common types being polyethylene terephthalate and polypropylene (PP),” said Dr Ranjith Ramasamy, the lead author of the study.
Microplastics can enter the human body through ingestion, inhalation and skin contact. They are present in the air, water, and food, especially in items like seafood, sea salt and bottled beverages.
The study authors also pointed out that because the microplastics are small and have a large surface area, they can “engage in chemical interactions with physiological fluids and tissues, raising concerns about their persistence, bioaccumulation and potential toxicity. This may be exacerbated by their ability to carry pathogens and pollutants.
A separate study published in Toxicological Sciences examined the presence of microplastics in male reproductive organs. It found 12 different types of microplastics in dogs and human testis samples. In dogs, researchers found that higher amounts of certain microplastics were associated with reduced sperm counts and testicle weight.
Among humans and dogs, the most common type of polymer was polyethene, and the second most common was polyvinyl chloride (PVC). PE is commonly used in packaging, water supply systems, plastic bags, bottles, food containers, carpet films and agricultural films. PVC is also common, used in construction, medical equipment, packaging, and electronics insulation.
Scientists also opined that microplastics, previously found in blood and body organs such as kidneys, embryo, placenta, lung, liver, spleen, intestines, brain, skeletal muscle, liver and brain may also penetrate the testicles and semen. They also believed that high levels of microplastics, which can accumulate over time, can potentially reduce testosterone production and sperm production. Such effects, they noted, may be irreversible.
According to ScienceDirect, “microplastics disrupt the body’s interactions between the nerves and the glands and organs that make hormones. By so doing, they influence how sex-related hormones are made.
“In the reproductive system, microplastics interfere with the blood-testis barrier, impairing spermatogenesis in males and causing placental dysfunction, ovarian atrophy, endometrial hyperplasia, and fibrosis in females. Moreover, microplastics potentially affect offspring’s lipid metabolism and reproductive function,” says the journal.
It adds: “Chemicals in plastics, like bisphenol A (BPA), can interfere with hormonal functions and potentially compromise fertility by mimicking or blocking natural hormones in the body. Chemicals associated with plastics are known to interfere with critical reproductive processes, including HPG Axis (hormone-regulating mechanism) and testosterone biosynthesis, spermatogenesis (development of sperms), oogenesis (development of ova), and the development of the placenta and embryo.”
Another study by the National Library of Medicine showed that microplastics in the body led to reduced testosterone, a decrease in the production of sperm and sperm quality, and increased sperm disorders, including defects in the quality or quantity of sperm produced.
Science shows that humans expose themselves to microplastics through ingestion, inhalation, and dermal contact. This is because microplastics have “infiltrated atmospheric, freshwater, and terrestrial ecosystems, penetrating commonplace consumables like seafood, sea salt, and bottled beverages.”
Therefore, reducing exposure to them can be achieved by reducing the use of single-use plastics, filtering tap water, or choosing fresh food over frozen food found in plastic containers that need to be microwaved.
