A recent study has revealed that being exposed to air pollution during pregnancy can have negative effects on the reproductive health of adult males.
New research has discovered that being exposed to common air pollutants while in the womb can decrease the quality of semen and raise the chances of developing reproductive system disorders in men.
The study conducted by Rutgers University, which went through a peer-review process, examined the potential impact of exposure to particulate matter known as PM2.5 and nitrogen oxide on the anogenital distance of fetuses and newborns.
Anogenital distance is an important indicator of reproductive health, specifically in relation to hormone levels, semen quality, fertility, and reproductive disorders. The research has found a probable connection between anogenital distance and exposure to pollutants.
According to Emily Barrett, the lead author of the study and a professor of biostatistics and epidemiology at Rutgers School of Public Health, observing shorter anogenital lengths indicates reduced testosterone activity in the womb. This could potentially affect fertility and reproductive health in the future.
Recent research has raised concerns about the decline in semen quality worldwide, which has previously been linked to exposure to other harmful substances such as PFAS and phthalates. Sperm concentration levels have decreased by 51% in recent years, and the findings from the Rutgers study indicate that air pollution may also play a role in this decline, according to Barrett.
PM2.5 is among the most common and well-studied air pollutants, and is linked to cancer and respiratory and circulatory disease. Among common sources are diesel exhaust, heavy industry emissions and wildfires, and the Environmental Protection Agency is poised to lower ambient air limits as evidence of its toxicity at smaller exposures becomes clearer.
Nitrogen oxide is a well-known harmful substance that has been associated with various health issues such as cardiovascular and lung diseases, stunted lung development in children, asthma, and other respiratory problems. Heavy industrial facilities like power plants and traffic are some of the main sources of this pollutant.
In animal research, the measurement of anogenital distance is utilized to assess the potential developmental harm caused by pollutants. A decrease in this distance may indicate that exposure to toxins is affecting the production of fetal testosterone.
It was hypothesized by researchers that the same phenomenon could apply to humans. They collected data on anogenital distance from The Infant Development and Environment Study (TIDES), a long-term study of approximately 700 expecting mothers and their offspring that began in 2010 in Minneapolis, Rochester, New York, San Francisco, and Seattle. This study measures anogenital distance in newborns and one-year-old boys.
The research team examined the correlation between TIDES data and air pollution levels in the residential areas where the participants resided. They discovered that increased exposure to PM2.5 during the first trimester “male programming window” was associated with changes in anogenital distance.
During this time, the male fetus typically produces testosterone which can impact the anogenital distance at birth.
According to Barrett, testosterone plays a crucial role in the growth of the male reproductive system. Any interference with the natural surge of testosterone during gestation can have significant consequences on future reproductive development.
The scientists also discovered a correlation between exposure to PM2.5 during “mini puberty”, a phase in early infancy characterized by high hormone production, and a shorter anogenital distance in male infants at one year of age.
Additionally, PM2.5 may contain other harmful substances such as cadmium and lead, which can disrupt the production of hormones. While the study did not involve women, Barrett noted that those with longer anogenital distances are more prone to developing polycystic ovary syndrome.
Pregnant individuals can best safeguard their unborn babies by adhering to air quality advisories and remaining indoors during periods of high pollution. N95 masks are suitable for outdoor use, while furnace filters with a MERV 13 rating are proven to effectively decrease indoor air pollution.
Barrett suggested that policymakers and regulators should take more action to control pollution instead of relying on individuals to protect themselves.
She stated that this is a matter of public health that affects us all and there should be a collective effort on a national and global level to decrease air pollution.