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Air Pollution Kills as Many People as Cigarettes

photo of smog in atlanta

Editor’s note: This story was updated Oct. 25, 2019 with a new analysis of air quality data by the Associated Press.

Oct. 8, 2019 -- When she turned 62 in 2012, Latifa Moosajee and her husband decided to downsize from their home in small-town Georgia. They moved into a brand-new townhouse in the commercial heart of Atlanta. “It was my dream home … close to my daughter’s family.”

Moosajee was excited to spend more time with her grandchildren and lead an active life in the city. But the very first year in her new home, she began to wheeze and have trouble breathing. At first, she tried allergy pills, thinking it was just a rough ragweed season. Over the next 5 years, she had longer and longer stretches of wheezing with trouble breathing, and she needed more and more medicines. She started short-acting inhalers, then long-acting inhalers, and eventually needed steroids just to keep her airways open.

The winters were the toughest. “For months at a time I had no energy… I could barely breathe,” Moosajee said. Her lung doctor ruled out the usual suspects. She had no history of lung disease. She didn’t smoke. No one around her smoked. She hadn’t changed her diet or started using new products in her home.

The only times she had similar problems were on her rare trips to India, which has some of the highest pollution levels in the world.

Figuring that out helped her zero in on the gridlocked street outside her window in Atlanta. “The cars pack the road from morning to night; only the evening would be clear.” Moosajee and her doctor began to suspect the polluted air she was breathing in for years was taking a toll on her health.

For millions of Americans like Moosajee, every breath brings toxic air deep into the lungs. There, pollutants can get into the bloodstream and cause damage throughout the body. The American Lung Association’s 2019 “State of the Air” report shows that more than 141 million people live in counties with unhealthy air, an increase of 7 million people from the 2018 report.

In the U.S., the nation had more polluted air days in the past two years than just a few years earlier, according to the Associated Press. Its analysis of data from the Environmental Protection Agency (EPA) found there were 15% more days with unhealthy air than there were on average from 2013 through 2016.

The science clearly shows that unhealthy air is dangerous. Air pollution, especially invisible, airborne particle pollution -- known as PM2.5 -- increases the risk of serious health problems. And it can kill. Even very low levels play a role in death from heart and lung diseases.

The connection between air pollution and health hazards is so strong that the director-general of the World Health Organization, Tedros Adhanom Ghebreyesus, PhD, calls air pollution the “new tobacco.” Recent estimates show that simply breathing polluted air played a part in the deaths of over 8 million people worldwide, more than the number of deaths from tobacco.

Richard Muller, PhD, a physicist and climate researcher at the University of California, takes the tobacco comparison one step further. Based on his work, in 2018, the average American was exposed to the health harm of about one-third of a cigarette every day. While a third of a cigarette a day may not sound like much, it adds up to over a hundred cigarettes in 1 year, and over 1,000 in 10 years. The health risks from inhaling air pollution add up, too, hitting every man, woman, and child in the U.S., he says.

“Air pollution is the greatest environmental disaster in the world today. … In my mind, it is scandalous that we’re not paying more attention to it,” Muller says.

Are We Are All Smokers?

Muller cautions that he is not suggesting that breathing in air pollution is actually the same as smoking a cigarette. It’s more like a mathematic illustration of how both can cause similar harms over a while.

Yet research shows that the health risks from cigarette smoking and air pollution are similar. A recent study found that breathing air with mild increases in air pollution levels over 10 years caused the same type of lung damage seen after 29 years of smoking a pack of cigarettes a day.

Air pollution also carries many other health risks associated with smoking -- from lung cancer and emphysema to heart disease and stroke. Like cigarettes, even small amounts are not safe. The more we inhale, the higher the risks.

Researchers have found that even modest increases in particle pollution raise the risk of dying from heart or lung disease and lung cancer. People who have never smoked are also more likely to get lung cancer and die from it as air pollution levels increase.

Pretty much everyone, everywhere is inhaling air pollutants without knowing it, which is partly why air pollution causes health problems in so many people, says Arden Pope, PhD, a professor of economics at Brigham Young University and world-renowned expert on the impacts of air pollution. He prefers to equate air pollution to secondhand smoke, rather than actual smoking. He explains: “Living in an area with high pollution is more like living with people who smoke two to three packs a day.”

There’s also another big difference. Unlike cigarettes, air pollution usually doesn’t come with a warning label or a telltale odor. For most of us, there are no signs that we are “inhaling” until the damage is done. And we don’t have control over the air we breathe.

What Are We Inhaling?

Cigarette smokers breathe in over 7,000 chemicals whenever they light up, and at least 69 of these are known to cause cancer.

The makeup of air pollution is very different and depends on where we live. In the U.S., pollution from fossil fuels is the biggest killer, with models estimating  close to 200,000 deaths a year. From cars to power plants, burning fossil fuels like gas and coal releases many dangerous pollutants into the air. Every time we start our engines, cancer-causing toxins like benzene, along with dangerous gases and particles, fill the air. Whenever coal is burned, dangerous fine particles, mercury, lead, and other heavy metals spread through the sky. Even natural events like wildfires can damage our health, sending particles and hazardous gases far into the air.

These gases and toxins can blend through chemical reactions to form ozone and fine particle pollution, the most common and most harmful pollutants found throughout the U.S. and around the world.

Particle pollution is not really one thing. It is an umbrella term for any tiny particles, smaller than a grain of sand, mixed with liquid. The smaller the particles, the more effective they are at evading the body’s defenses. Fine and ultrafine particles are considered the most dangerous because toxic contaminants like metals and tiny allergens can hitch a ride on them and travel deep into the lungs. 

Ozone is the main part of smog.  Ground-level ozone can cause breathing problems, asthma flares, and lung inflammation. Toxic ozone is formed when certain gases and chemicals cook in the heat of the sun. As summer temperatures warm globally because of climate change, researchers say, exposure to ozone will become much more common and last longer.

What Happens When We Inhale?

In the short term, spikes in air pollution can worsen medical problems like asthma and heart disease. Over the long term, even low-level exposures considered acceptable by the EPA can play a role in developing lung and heart diseases. More and more research now finds links to damage in virtually every organ in our bodies, from our brains to our bones.

Dean Schraufnagel, MD, a University of Illinois at Chicago pulmonologist and director of the Forum of International Respiratory Societies, helps people make the connection between “the steady stream of ‘low-dose’ pollution” we inhale and the medical problems that can come years down the line.

 “Air pollution really is a silent killer. … By the time people have the lung cancer or the heart disease, they think … ‘oh, that’s bad luck or bad genes’; they don’t realize that air pollution over many years also may have played a role.”

Young children and older adults face the highest risks because their body’s defenses are less robust than healthy adults. For children, the damage can start even before they are born. Air pollution can cause early birth and low birth weight, putting babies at risk of lifelong health problems.

After birth, children face more risks from air pollution because their organs are still developing. They also inhale higher amounts of pollutants because they tend to spend more time outside, breathe faster than adults, and breathe more through their mouths.  The nostrils are much better at keeping pollutants out of the body than the mouth.

Breathing in polluted air during a time of critical development can also damage the brains of young children, affecting how they think and feel. Polluted air has been linked with autism, lower intelligence, attention problems, and a higher risk of mental health problems like anxiety.

The aging brain may see damaging effects from air pollution as well. Older adults who live closer to busy roads have higher risks of getting dementia. And spikes in air pollution can lead to strokes.

Researchers have started looking into why air pollution has such far-reaching effects in our bodies. Beyond direct damage to many parts of the body, when the lungs are bombarded with pollutants, a set of signals lead to the release of chemical messengers in the blood.  These chemicals can damage the lining of blood vessels, increase the risk of blood clots, and cause inflammation that can affect every organ in our body.

Silent Killer

Most of us are not aware of the pollutants we are breathing in. Even fewer are paying attention to the long-term health risks of air pollution.

In the U.S., air monitoring stations collect data on pollutants like particulate matter and ozone so people can be alerted when levels are higher than what is considered acceptable. But these monitors don’t provide neighborhood-level information and may not catch “hot spots” where people like Moosajee live. This is quite true for people living on busy roads. Even on alert days, people who don’t have symptoms may not think they should heed the warnings.

Two young app developers in Paris want to change that.

Amaury Martiny came across Muller’s air pollution-to-cigarette calculation about a year ago and describes it as an “aha” moment.

Martiny and designer Marcelo Coelho created a free app using Muller’s formula and PM2.5 data from hundreds of air quality data stations in cities all around the world. When the app is open, it finds your phone, finds the closest air monitor data for PM2.5, and converts it into the “equivalent” number of health-damaging cigarettes. They found that many of their U.S. downloads happened during the California wildfires in 2018, when the app would have shown a staggering 45 cigarettes per day in the area of the wildfire.

Martiny and Coelho stress that their “main goal is to raise awareness about the risk of air pollution. … What was amazing about the equation was it transformed this very abstract scientific notion of PM2.5 to something that was really tangible to basically everybody. … Everybody knows the effect a cigarette can have on your body.” And everyone knows that there aren’t “safe levels” for cigarette smoking. 

Why Don’t We Cut Back?

Over the last 20 years, Americans have mostly been protected from high levels of air pollution because EPA programs have greatly improved air quality. The yearly average of fine particles has decreased by 40% since 2000. According to a 2017 Office of Management and Budget (OMB) report to Congress, the EPA’s air rules save tens of billions of dollars.

Most of the savings come from what are known as “co-benefits,” meaning benefits to human health that result in lower health care costs and fewer premature deaths.

 “We’ve done a good job of reducing our air pollution. It’s improved our health, and we’ve done it at a time of rapid economic expansion,” Pope says. “It’s very clear that this isn’t a tradeoff between clean air and jobs. The reality is we can reduce our air pollution while at the same time improving economic activity. So it’s sort of a win-win situation.”

But recent concerning changes at the EPA may affect air quality and health in the not-so-distant future. EPA leadership has moved to replace independent science advisers from important committees, like the Clean Air Scientific Advisory Committee (CASAC), and halted a panel of experts that have been studying the most up-to-date particle pollution science.

But the American Lung Association and other health advocacy groups have raised the alarm about EPA plans to limit or gut many of the programs that have cut air pollution and improved the health of American communities. The organization cites:

  • Plans to roll back fuel efficiency standards for cars and trucks
  • Repeal of the Clean Power Plan and replacement  with a rule that may increase emissions
  • Changes to how the EPA measures benefits to human health when cutting down on pollution from toxic air pollutants, including mercury and PM2.5

According to experts, all of these changes will likely lead to a reversal of the progress in reducing air pollution and preventing related deaths.

What Happens When We Quit?

Though levels of air pollution are better in most communities in the U.S. than other places in the world, we can still do more to reduce our risk of long-term health problems. “The only thing that makes sense based on the evidence is that we should continue to try to reduce our exposure to air pollution. … It doesn’t come without effort, and it doesn’t come without vigilance,” says Pope.

Some of what we know about the health benefits of cleaner air comes from “natural experiments,” where researchers study what happens to people in areas after pollution levels come down, like when large factories shut down or traffic routes change. Most of these studies show improvements to health quickly.

After coal and oil power plants closed in California, there were fewer preterm births in neighboring communities. New electronic tolls (E-ZPass) in New Jersey and Pennsylvania reduced traffic congestion from idling cars, improved birth weights, and lowered early births for mothers living less than 1.5 miles from toll plazas. When air pollution was controlled during the Olympics in Beijing, birth weights for babies in the area improved. And when traffic was rerouted during the Olympics in Atlanta, there were fewer ER visits and hospitalizations for asthma for local children.

Worldwide, research shows that cleaner air from lower emissions leads to less asthma, lungs that work better, and less coughing, congestion, and mucus in young children.

How Can We Protect Ourselves?

The best way to reduce the risk of health problems is to avoid breathing in polluted air. This is especially true for pregnant women, babies, children, older adults, and those with chronic medical problems. But it’s hard to do if you live in high-traffic areas or close to polluting factories.

Facemasks, specifically those called respirators masks, can filter particle pollution if worn the right way. The main problem is that people have to buy the right mask and wear it with an airtight seal; otherwise, it won’t filter out harmful pollution. Also, most masks don’t filter out certain toxic gases and can still allow harmful lung irritation.

For most people, paying attention to air quality alerts is a good start. Avoiding outdoor activities on “unhealthy air days” is very important. Beyond air quality alert days, doctors recommend walking or exercising in areas far from high-traffic roads and idling cars or buses. High-quality HEPA air filters in the home can lower airborne particles. And eating a healthy diet and exercising can also lower the health risks from air pollution.

As for Moosajee, after years of trying air filters in her home and taking multiple medicines to improve her breathing, she eventually decided to move away. Two years ago, she found a home on a quiet, tree-lined neighborhood in Atlanta. Now 69, she sees a vast improvement in her breathing. “I see a big difference. I don’t use any steroids, no inhalers. I only use allergy pills for a few weeks in the year. I expected these problems when I went to India. … I can’t believe I would have the same problems here.”

But for most people, moving is not an option. Schraufnagel stresses that the most important thing people can do is to learn about the risks of air pollution. “If enough people say ‘we don’t want dirty air, we want clean air, and we’re afraid that it’s affecting our health’ .... then decision-makers will need to step up to make sure that the automobiles are cleaner and power plants are cleaner” so we can all breathe cleaner air.

WebMD Health News Reviewed by Hansa D. Bhargava, MD

Sources

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