Microplastics have been detected in human testicular tissue and are associated with significantly lower sperm counts and signs of tissue damage, according to a new meta-analysis presented at the OB European Society of Human Reproduction and Embryology.
The findings suggest that environmental exposure to microplastics may be linked to male infertility.
Investigators analyzed 15 studies published between 2010 and 2024, covering a combined total of 1,200 men who underwent infertility evaluations. Testicular tissue samples were examined using electron microscopy and spectroscopy to detect and quantify microplastic particles.
Microplastics were found in 68% of the samples analyzed. The most common types identified were polyethylene and polystyrene, with particle sizes ranging from 1 to 20 micrometers
Men whose testicular tissue contained microplastics had a significantly lower average sperm concentration of 12 million per milliliter compared with 26 million per milliliter in those without microplastics. This difference was statistically significant (P<.01), suggesting a strong association between microplastic presence and reduced sperm count.
In addition to lower sperm concentrations, histological analysis of tissue containing microplastics revealed inflammation, disruption of seminiferous tubules—structures critical for sperm production—and signs of oxidative stress, a process known to damage cells and DNA.
Men with detectable microplastics in their tissue samples were also more likely to report higher environmental exposure to microplastics, commonly through sources such as contaminated water and food packaging. Although lifestyle and exposure histories were collected, investigators noted that some confounding variables—such as genetics, occupational exposure, and other environmental factors—were not consistently controlled across all included studies.
The authors emphasized that, although the findings suggest a link between microplastic accumulation and impaired fertility, methodological differences across the studies introduce variability in detection methods and clinical criteria. While the association is statistically significant, a direct causal relationship has not yet been established.
Because microplastic detection techniques are still evolving and long-term reproductive outcomes remain unclear, investigators called for additional prospective studies to confirm the findings and to explore mechanisms of action.
The study adds to a growing body of research suggesting that microplastics—widespread environmental pollutants—can infiltrate sensitive human tissues, including reproductive organs. The findings underscore the need for further investigation into the reproductive effects of chronic exposure to microplastics and broader public health measures aimed at reducing environmental contamination.
As microplastic pollution continues to rise globally, understanding its impact on human health, particularly fertility, remains of interest.
Source: Human Reproduction