[TITLE>Air Pollution Exposure Linked to Epigenetic Changes in Sperm That May Affect Male Fertility]
Air pollution appears to disrupt sperm gene function, with new research indicating that exposure to common pollutants is associated with epigenetic changes that could impact male fertility.
The study, presented at the European Society of Human Reproduction and Embryology annual meeting in London, is among the largest of its kind. It found that men exposed to air pollutants during sperm development showed DNA methylation changes—chemical modifications that affect gene expression without altering the underlying genetic code.
Ozone and nitrogen dioxide emerged as the pollutants most strongly linked to these epigenetic alterations. The research followed over 2,000 men in Salt Lake City, Utah, between 2013 and 2017, with participants providing semen samples upon enrollment and at regular intervals thereafter.
Scientists analyzed sperm DNA methylation in 1,220 men who provided samples at the six-month follow-up. They identified 39 DNA changes associated with air pollution exposure, with ozone and nitrogen dioxide showing the strongest influence. While most epigenetic modifications are typically erased during early embryo development, certain genes—including GNAS, which has previously been linked to reduced semen quality and fetal development—may retain these alterations.
Dr. Carrie Nobles, an epidemiologist at the University of Massachusetts Amherst who led the research, noted that while the findings suggest a connection between air pollution exposure and sperm DNA changes, further investigation is needed to determine clinical significance for male infertility.
Independent experts acknowledged the study’s contribution to understanding how airborne pollutants affect reproductive health. however, additional research is required to establish whether these epigenetic changes directly impact fertility outcomes.
