Inhaling trashy air can seem unavoidable—and while you might notice it irritating your lungs, it may also impact your swimmers. You read right: Research shows air pollution may affect the quality of your sperm. And it’s a big deal.
Experts in reproductive and public health have been sounding the alarm about a global fertility crisis. During the past 70 years, birth and fertility rates have sharply declined, according to data from the World Economic Forum.
While several reasons may account for these drops, air pollution’s effect on sperm may be a significant part of the problem, ays New York Urology founder and chief physician, David Shusterman, M.D. “There have been several notable studies on the impact of pollution on sperm quality.”
Greg Brannon, M.D., F.A.C.O.G., medical director of Optimal Bio and author of The Hormone Handbook, agrees. “Studies have shown that exposure to air pollution can cause DNA damage in sperm cells, a decrease in sperm count, and impaired sperm motility—all of which can negatively impact fertility and even increase the likelihood of birth defects in offspring,” he says.
“Moreover, air pollution can cause hormonal imbalances in men, further affecting reproductive health.”
How Does Air Pollution Affect Sperm?
Here’s the dirt on what happens when you breathe scummy air: Pollution is composed of various pollutants, such as fine particulate matter, nitrogen dioxide, ozone, and sulfur dioxide—which can enter the bloodstream when inhaled, says Brannon.
And, as Shusterman explains, “Exposure to environmental pollution may cause alterations in the hypothalamic-pituitary-gonadal (HPG) axis: your body’s system for regulating the production and dispersion of sex hormones.”
Common air pollutants—including those found in fumes from motor vehicle exhaust and cigarette or wood smoke—are known endocrine disruptors.
When absorbed in the body, endocrine disruptors can tweak normal hormone levels, mimic the body’s natural hormones, or alter hormone production—generally messing up their normal functions (1).
Dioxins can also act as endocrine disruptors. They’re common by-products of many industrial processes and linked to an array of serious health problems (not just reproductive ones). (2)
Even more troubling? Dioxins resist degradation over time. The exact mechanism for dioxins’ impact on reproductive functions in humans isn’t totally clear. Some research suggests damage may occur as early as conception and may also affect spermatogenesis (sperm creation). (2)
“Studies show the effects of pollution are more prominent when exposure occurs during the initial part of spermatogenesis,” Shusterman says. “The damage caused by environmental pollution can be either short- or long-term, depending on the duration and intensity of exposure.”
Where Is Air Pollution and Sperm Damage Most Common?
No surprise, here: Some of the most populous spots in the country also happen to have the worst year-round particulate pollution, according to the American Lung Association, including the metropolitan areas of San Francisco, Los Angeles, Phoenix, Detroit, Indianapolis, Pittsburgh, and Houston.
But air pollution isn’t just an urban issue. Certain pesticides and herbicides—like some sprayed on crops in agricultural areas—are also pollutants and endocrine disruptors. A review published in 2020 found herbicides and pesticides such as DDT and DBCP can negatively affect spermatogenesis and motility. The same study also suggested a link between organophosphates (a common type of pesticide) and reduced sperm count and viability. Atrazine, a common organophosphate, has also been connected to reduced sperm motility. (3)
Air pollution and its effects on sperm quality aren’t just American problems, either. A 2022 study published in JAMA of more than 33,000 men in China with an average age of 34 years revealed exposure to particulate matter in air pollution adversely affected the subjects’ sperm motility. What’s more, nine out of 10 people around the world regularly breathe highly polluted air, according to the World Health Organization. (4)
PROTECT YOUR FERTILITY
Preventing Environmental Damage to Sperm
“There is no guaranteed way to completely ‘pollution-proof’ sperm,” Shusterman says. “But you can reduce your exposure or its impact.”
Here are some recommendations:
Steer clear of high-pollution areas (if you can)
This might be easier said than done, depending on where you live or work. The American Lung Association recommends staying inside or at least working out indoors on high-pollution days. (Shusterman suggests using air filters when at home, too, for added protection.)
It’s also a good idea to skip exercising near high-traffic areas, such as freeways. And while camping and getting out into the wilderness is ideal for scoring fresh air, avoid breathing in smoke from campfires or burn pits—and of course, don’t smoke or vape yourself.
Pack your plate with plants
Air pollution can cause oxidative stress in the body, which occurs when there is an imbalance between damaging free radicals and your body’s store of antioxidants to remove them. A large body of evidence suggests oxidative stress can play a role in cellular damage and inflammation—which could lead to cancer and chronic illness, such as heart disease and diabetes. (3, 5)
It can also impact your sperm. A 2017 study found sperm are “extremely vulnerable” to oxidative stress, and that it may lead to decreased sperm motility. (5)
“Adopting a healthy diet rich in antioxidants, such as fruits, vegetables, and whole grains, can help reduce oxidative stress and improve sperm health,” Brannon says.
Well-known antioxidant substances include vitamins C and E, polyphenols, and minerals such as zinc. Selenium also has antioxidant properties and manganese contributes to another important antioxidant, superoxide dismutase, which the body makes. Colorful fruits and veggies are packed with these vitamins and minerals, but nuts, seeds, whole grains, and legumes contain antioxidants, too.
Choose organic produce, if possible: Not only will you avoid synthetic and chemical pesticides, but research has shown that organic produce may contain higher levels of certain antioxidants than conventional counterparts. (6)