By Girish Linganna
May 17: Scientists at the University of New Mexico found microplastics in the testicular tissue of both humans and dogs. The study, which analyzed testicle samples from 47 dogs and 23 humans, identified 12 different microplastics, according to a report by Interesting Engineering, a media outlet in the US.
The scientists aimed to measure the amount and types of microplastics found in both dog and human testicles. They also explored whether these microplastics were linked to changes in sperm count and the size and weight of the testicles and epididymis, which are key parts of the male reproductive system.
The epididymis is a long, coiled tube attached to the back of each testicle that stores and carries sperm, allowing them to mature.
This study is significant due to the limited information available on how microplastics affect sperm quality. One of the researchers involved in the study shared that at first, they were unsure if microplastics could even enter and affect the reproductive system.
The researcher expressed surprise at the findings from the dog samples, and was even more astonished by the results from human samples.
Microplastics May Affect Sperm Quality
In their analysis, the scientists stripped away fats and proteins from the samples to simplify the identification of plastics. They detected 12 different types of microplastics using a chemical technique designed to pinpoint complex organic materials.
The findings revealed that the concentration of microplastics was 122.63 micrograms per gram in dogs and 328.44 micrograms per gram in humans.
In both humans and dogs, polyethylene (PE) was the most prevalent type of microplastic found. PE is one of the most commonly used plastics.
The researchers also noted a link between certain plastics and lower sperm counts in dogs. Specifically, they observed a higher amount of polyvinyl chloride (PVC) in dog samples. PVC is one of the most widely used plastics worldwide, with an annual usage exceeding 48 million tonnes.
As noted, PVC can emit chemicals that disrupt spermatogenesis, the process through which sperm cells are produced.
Why Study Human and Dog Testicles?
The researcher noted that the process of sperm production in dogs is physically more similar to humans, both in its mechanism and sperm count.
Additionally, both dogs and humans are subject to the same environmental factors.
It's important to mention that previous research has demonstrated how substances like heavy metals and pesticides can affect the endocrine system.
What Was the Source of the Samples?
The researchers sourced human tissue samples from the New Mexico Office of the Medical Investigator, where they were primarily gathered during autopsies and were of anonymous origin.
Autopsies are medical examinations of a body after death. These examinations are performed to determine the cause of death, investigate how a person died, or study the effects of diseases or injuries on the body.
For dog tissues, they were collected from animal shelters and veterinary clinics during procedures for dog sterilization.
The average age of the men in the autopsy samples was 35, suggesting that exposure to microplastics begins earlier than previously assumed.
(The author Girish Linganna of this article is a Defence, Aerospace & Political Analyst based in Bengaluru. He is also Director of ADD Engineering Components, India, Pvt. Ltd, a subsidiary of ADD Engineering GmbH, Germany. You can reach out to him at: girishlinganna@gmail.com)