15 Scary Things Air Pollution Does to Your Body
Air pollution—namely ozone and tiny particles—are doing more damage than anyone previously thought. Here’s what you need to know and how to protect yourself.
Raises the risk of autism
Pregnant women who live in smog-filled areas may be twice as likely to have children with autism, nationwide research suggests. Don’t hit the panic button just yet, as these findings are far from definitive. Exactly how, or even if, air pollution affects the developing brain remains unknown. This association was strongest when the exposure occurred during the third trimester of pregnancy, and the greater the exposure, the greater the risk, the study found.
Damages your heart and lungs
Research out of Duke University shows that exposure to air pollution on city streets may counter the beneficial health effects of exercise in adults older than 60. Specifically, short-term exposure to traffic exhaust on a busy street can cancel out the positive effects that two-hour stroll would otherwise have on the heart and lungs.
“This adds to the growing body of evidence showing the negative cardiovascular and respiratory impacts of even a short, two-hour exposure to motor traffic pollution,” says Junfeng “Jim” Zhang, professor of global and environmental health at Duke, in a news release. “It highlights the need for stricter air quality limits and better traffic-control measures in our cities.” To arrive at their findings, researchers recruited 119 volunteers over the age of 60 who were either healthy, had stable chronic obstructive pulmonary disease (COPD), or stable heart disease. Study participants walked for two hours midday at one of two London locations: in a relatively quiet part of Hyde Park, or along a busy section of Oxford Street where pollution tends to exceed air quality limits set by the World Health Organization. The researchers measured each volunteer’s lung capacity, blood pressure, blood flow, and arterial stiffness before and after the walk.
The Hyde Park walkers did much better within the first hour—volunteers’ lung capacity improved significantly and it lasted for more than 24 hours in many cases. By comparison, the group strolling along polluted Oxford Street benefited very little during at first, and experienced no benefits later. What’s more, walking in Hyde Park eased arterial stiffness in the volunteers by as much as 24 percent; walking along Oxford Street yielded much smaller gains—about 16 percent at most.
Lowers fertility in men
Monkey Business Images/Shutterstock
Uh oh is right. A study shows that air pollution has been linked to poorer sperm quality. “Our next step is to study if pollution is directly associated with infertility,” says lead study author Xiang Qian, PhD, an assistant professor at the Jockey Club School of Public Health and Primary Care at the Chinese University of Hong Kong. Qian and colleagues analyzed sperm from 6,475 men aged 15 to 49 years, and found that men who breathed in more pollution were more likely to have abnormally shaped and smaller sperm. Of note, these men had more sperm than their counterparts who were not exposed to high labels of particulate matter, but it was of poorer quality. “We speculate this might be due to the compensation mechanism, but pollution is associated with lower normal sperm,” Qian says.
Pollution in the air may increase the risk for osteoporosis and related fractures, according to research in the journal The Lancet Planetary Health. It doesn’t take much either. Even a small increase in levels of an airborne particle called PM2.5—sources include car exhaust, wood smoke, and power plant emissions—may lead to an increase in bone fractures in older adults. What’s more, this risk was greatest in low-income communities, the study found. Participants living in areas with higher levels of PM2.5 and black carbon, a component of air pollution from automotive emissions, had lower levels of a key bone-related hormone called parathyroid hormone or PTH. They also had more porous bones than people exposed to lower levels of these pollutants. Exactly how pollution can lead to bone loss is not completely clear, but it is similar to what has been observed with smoking.
You’d be surprised how air pollution can affect organs other than your lungs, like your kidneys. Where you live may also play a role: Researchers at Washington University School of Medicine in St. Louis and the Veterans Affairs (VA) St. Louis Health Care System culled national VA databases to evaluate the effects of air pollution and kidney disease on nearly 2.5 million people over a period of 8.5 years, beginning in 2004. They compared data on kidney function to air-quality levels collected by the Environmental Protection Agency (EPA) as well as the National Aeronautics and Space Administration (NASA).
The researchers discovered a link: They identified 44,793 cases of kidney disease and 2,438 cases of kidney failure that could be tied to levels of air pollution that had exceeded the EPA’s threshold. (The study appears in the Journal of the American Society of Nephrology.) How could bad air harm your kidneys? Microscopic particles of pollution can enter the bloodstream; since the kidneys main task is to filter the blood, the organ ends up collecting loads of pollutant particles. “The higher the levels of air pollution, the worse it is for the kidneys,” says study author Ziyad Al-Aly, MD, assistant professor of medicine at Washington University and the VA’s director of clinical epidemiology, in a news release. “However, no level is completely safe. Even at relatively low levels, there was a relationship between particulate matter concentrations below the EPA thresholds and kidney disease.” People living in Southern California and large regions of the South, Midwest, and Northeast were at the highest risk, the study showed. Check out what these iconic skylines would look like without air pollution.
“There is a lot of data in places like China, where pollution is bad, that show it can cause pigmentation changes and accelerate aging of the skin,” says Adam Friedman, MD, associate professor of Dermatology and director of the Supportive Oncodermatology Clinic at George Washington School of Medicine and Health Sciences in Washington, DC. The substances in pollution damage skin cells and interfere with the skin’s ability to repair itself. The result is age spots, wrinkles, and loose folds, says Dr. Friedman.
Many sunscreens now include protective shields to help keep pollution from damaging skin, such as Glossier’s Daily sunscreen SPF 35, L’Oreal Dermo-Expertise UV Perfect 12H Longlasting UVA/UVB Protector, and Elizabeth Arden Prevage City Smart Broad Spectrum SPF 50 Hydrating Shield. But buyer beware (at least for now), Dr. Friedman says. “While we know that there is a connection, the question is what is the best thing to use for protection.”
While the data is less clear, says Brian M. Grosberg, MD, director of the Hartford Healthcare Headache Center in Hartford, Connecticut, there may be a connection: “It is very difficult to say with certainty if air pollution is causally related to headache or just has an association.” One study found increased hospital admissions for migraines and other headaches on days when air pollution readings were high. Keep a headache journal and see if you can find any patterns related to air-pollution levels or other triggers to stay ahead of yours.
Causes lung disease
It makes sense: Pollution hits lungs the hardest. Fine particles are tiny enough to be inhaled deep into the lungs “We know exposure to high levels of ozone or PM pollution can worse lung function,” says Anthony N. Gerber, MD, PhD, a pulmonologist in the Division of Pulmonary, Critical Care and Sleep Medicine at National Jewish Health in Denver. “If you have existing decreased lung function from asthma or smoking-related lung disease, you can wind up in the ER, miss school, or need rescue medications more often on high pollution days.”
Raises risk of heart attack or stroke
Pollutants and your heart are a bad mix: “Pollution can induce inflammatory pathways within the lungs that can send signals out to the whole body, resulting in stroke or heart attack,” Dr. Gerber says. “We know rates of heart attack or stroke are higher on bad pollution days.” Masks don’t really work all that well, but tracking pollution can help you make better decisions about when to stay indoors. The EPA tracks air quality, so you can stay informed. If it is a high pollution day, maybe hit the gym instead of going for a run outside, he says. Make sure to visit these places before they disappear due to climate change and pollution.
Ups diabetes risk
Add diabetes to the long list of diseases caused or worsened by pollution. Air pollution contributed to around 3.2 million cases of diabetes and the loss of 8.2 million years of healthy life in 2016, according to a study published in The Lancet Planetary Health. “Animal studies had suggested that polluted air can cause glucose intolerance, which is a hallmark of diabetes,” explains study author Ziyad Al-Aly, MD, a nephrologist in Saint Louis and the Associate Chief of Staff for Research and Education at the Veterans Affairs St. Louis Health Care System. Snippets of data in humans had hinted at a relationship between air pollution and diabetes. And this study adds to that body of research. “Particulate matter with a diameter of less than 2.5 micrometers is small enough to enter the bloodstream and affect metabolism and impair a body’s ability to use glucose for energy,” Dr. Al-Aly says.
Increases cancer risk
The International Agency for Research on Cancer, which is part of the World Health Organization (WHO), classifies outdoor air pollution as a cause of cancer, namely lung cancer and bladder cancer. And the statistics are staggering: In 2010 alone, for example, 223,000 people worldwide died from lung cancer caused by air pollution. Here’s what the world’s most polluted beaches look like.
Fuels your teen’s reaction to stress
Teens with anxiety and depression may be particularly vulnerable to the effects of air pollution on stress. In a study published in the journal Psychosomatic Medicine in 2019, researchers looked at 144 California adolescents who performed stressful tasks. They found that the fight-or-flight response was greater for teens living in neighborhoods with high levels of pollution, especially those who had a history of anxiety and depression. The body’s fight-or flight response is designed to protect us from impending danger, and it triggers a burst of stress-related hormones. That’s great when there’s a real threat, of course. But it can be harmful when it occurs often and in response to non-life-threatening situations.
Raises the likelihood of dying early
As many as 4.2 million premature deaths around the world are linked to outdoor air pollution. These deaths are largely due to heart disease, stroke, chronic obstructive pulmonary disease, and lung cancer, as well as acute respiratory infections in children, according to WHO. To do your part to combat this crisis, make these 25 tiny changes that can help cut back on air pollution.
Increases the risk of developing a psychiatric illnesses
Poor air quality may be linked to increased rates of bipolar disorder, according to research conducted in the United States and Denmark. The study, published in PLOS Biology in 2019, found that people who lived in polluted areas early in life were at a heightened risk for developing this psychiatric disorder. Researchers analyzed information from a U.S. health-insurance database comprised of 151 million individuals, then compared the claims to measurements of 87 potential air pollutants. Counties with the worst air quality had a 27 percent increase in bipolar disorder compared to those with the best.
Next, they applied the same methodology to data from Denmark to see if their findings held, and they did—especially for bipolar disorder. They also found an increased risk of depression, schizophrenia, and personality disorders among those who lived in polluted areas in Denmark. Because of the study’s limitations, however, the authors can’t say how—or even if—pollution causes these diseases to develop.
Dampens your problem-solving chops
For every increase of 2.5 micrograms per cubic meter in the fine-particle pollution level surrounding a teen’s home, performance IQ scores dip one point, according to research published in PLOS One in 2017. (Performance IQ measures reasoning and problem-solving abilities.) The 12-year study included more than 1,300 preteens who lived in neighborhoods across Los Angeles and surrounding counties. Researchers tested the teens’ IQ levels at ages 9 to 11, and again in young adulthood between ages 18 to 20, then compared results to pollution levels in their communities. Worried about where you live? These are some of the most (and least) polluted cities in the world.
Ziyad Al-Aly, MD, a nephrologist, Saint Louis, Missouri; Associate Chief of Staff for Research and Education, Veterans Affairs St. Louis Health Care System
International Agency for Research on Cancer: “Outdoor air pollution a leading environmental cause of cancer deaths.”
The Lancet Planetary Health:“The 2016 global and national burden of diabetes mellitus attributable to PM2•5 air pollution.”
Psychosomatic Medicine: “Fine Particle Air Pollution and Physiological Reactivity to Social Stress in Adolescence:The Moderating Role of Anxiety and Depression.”
WHO: “Ambient air pollution: Health impacts.”
PLOS Biology: “Environmental pollution is associated with increased risk of psychiatric disorders in the US and Denmark.”
PLOS One: “Socioeconomic disparities and sexual dimorphism in neurotoxic effects of ambient fine particles on youth IQ: A longitudinal analysis.”