Ambient air pollution has become one of the world's greatest killers. But physicians still differ on their involvement in fighting it.
As the human population grows ever larger, the world shrinks, according to William R. Barclay, MD. It took a full million years for humanity to reach a population of 1 billion persons. But it only took 120 years to reach 2 billion; 33 years to reach 3 billion; and 15 years to reach 4 billion, the former director of the American Medical Association (AMA) explained.
That population explosion sparked rapid urban development, Barclay noted in an essay, and an unprecedented strain on natural resources. As those resources are gobbled up, the world bears the burden of a massive increase in environmental pollution. Human beings are behind nearly all of it, he argued, and we’re likely to see a lot more human beings as time goes on.
Barclay wrote his essay in September 1970 — a point in time that stands almost exactly between present day and 1920, when he says the US was officially urbanized. In the 5 decades since, the global population has nearly doubled, North America became the most urbanized continent in the world, and ambient air pollution has become one of the leading causes of death worldwide.
In Barclay’s almost-prophetic analysis of growing pollution rates, he called on legislators and their constituents to seek answers to the pollution problems we’re facing. He also conceded he couldn’t offer any solutions— a troubling point when considering his expertise, and the public health implications of rising pollution rates.
For as much as the world has changed, many aspects of modern life remain the same as when Barclay penned his essay. We’ve come a long way in our ability to measure and treat pollution’s effects, but physicians — even those who specialize in treating the ailments that pollution causes – haven’t come to a consensus about how they can help their patients proactively achieve better health outcomes as pollution rates rise.
In an October 2017 study, researchers reported that deadly non-communicable diseases (NCDs) caused by ambient air pollution had increased by another 20% in the past 25 years. More people are now dying annually from pollution than from AIDS, malaria, and tuberculosis combined.
Lead author Philip J. Landrigan, MD, MSc, Professor of Environmental Medicine, Public Health and Pediatrics in the Arnhold Institute for Global Health at the Icahn School of Medicine, Mount Sinai, put this trend into forward-looking terms. Pollution-related deaths will increase by another 50% in the next 2 or 3 decades unless aggressive intervention is taken, he said. Residents of low-income and middle-income countries (LMIC), where urbanization and industrialization are gaining momentum, will continue to bear the brunt of the pollution burden.
“They have weak environmental agencies,” Landrigan said in an interview. “They're galloping ahead with industrialization without paying attention to the consequences.”
Coupled with a more recent analysis suggesting that fine particulate matter (PM2.5) exposure is significantly affecting the health of Medicare populations, and that decreasing 10 μg/cubic meter of fine particulate matter concentration is associated with an estimated increase of 0.61-0.20 years of mean life expectancy — Landrigan’s diagnosis of the Earth’s greatest illness is gaining support in the literature.
In an interview with MD Magazine, Landrigan said the annual rate of death from pollution would currently sit at 9 million people, if it were to account for the 70% of all NCDs it has been linked to. Current research suggests it’s associated with heart and lung disease, possibly diabetes, and even neurological conditions such as Alzheimer’s disease and multiple sclerosis.
The most compelling case of its severe effects, though, is in pediatric disease. Asthma rates in children have tripled in the past 40 years, according to Landrigan. That’s a rate that matches rising prevalence of obesity. Pediatric cancer, while easier to treat than it used to be, has also raised by 40%.
“One of the issues is that these substantial clinical findings have not trickled down to actual practice,” Landrigan said. Doctors may be comfortable educating the public on the relationship between pollution and asthma, but Landrigan doesn’t believe the average physician has been properly educated to address the health issues that stem from it. It’s an issue that can be traced all the way back to medical school.
“There’s minimal education about environmental risk factors, from medical school into practice,” Landrigan said. “I believe they only have to take about 6 hours of clinical training on environmental science.”
Though education may be lacking, some boots-on-the-ground physicians simply understand their limitations in addressing the issue.
Treating What They Can
Andrew Murphy, MD, is an award-winning allergist with 3 practices that sit a short drive from one of the most polluted regions in the Northeast in West Chester, Pennsylvania. Still, Murphy gives little consideration to the environmental issues found 40 miles east in Philadelphia.
“I know there’s some data through the years that shows when people are closer to high-population areas there are greater asthma rates,” Murphy told MD Magazine. “I live in a more suburban-rural area, so I don’t see it as much.”
Murphy doesn’t see the merit in giving his patients one more thing to worry about. What he finds more feasible is to emphasize allergen monitoring. He tells his patients with asthma to check the Environmental Protection Agency’s (EPA) air quality tracking site, AirNow.gov, routinely. If a patient suggests they are having more issues with symptoms, he advises switching therapies or non-medication measures to manage it. One thing he doesn’t do is tell them to get away from areas of higher pollution.
“I don’t have any control over the ozone count today,” Murphy said. “It’s just the way of an allergist — I’m trying to control allergens.”
Murphy finds he has a more hands-on role in addressing indoor pollutants, such as smoking tobacco or other harmful inhalants. He’s also become more engaged with issues caused by seasonal pollen — a challenge that’s amplified by measurements that indicate pollen seasons are getting longer and more potent, he said.
But even if Murphy wanted to be more authoritative on how pollution is affecting his patients, individual practices like his are not properly positioned to say. He believes health care providers in emergency departments are more likely to be versed on pollution health. He sticks to what he knows, and sees.
“I try to not be doom and gloom with patients because it doesn’t help much,” Murphy said. “We can control the indoor stuff. And for good or for bad, we spend most of our time indoors. That’s an environment we can control and try to make as safe as we can.”
There’s also a matter of resources and funding — which even for the most devoted clinicians can dictate how far they can go in pollution-based health intervention.
Pathology to Pollution Research
As a prominent researcher of pediatric asthma, Wanda Phipatanakul, MD, has a vested interest in pollution health. The professor of pediatrics at Harvard Medical School and director of the Asthma Clinical Research Center at Boston Children’s Hospital was born and raised by a family of doctors — her late mother was an allergist, which drove her to the field. After medical school, she went to a fellowship under a Boston-based allergist, and then finally to researching inner-city pediatric health.
Having worked for 15 years with a fully-staffed team of like-minded colleagues and a consistent bankroll from funding parties such as the National Institute of Health (NIH), Phipatanakul has become a leader in environmental intervention research. But she’s also understands the perspective of practicing colleagues like Murphy.
“There’s nothing wrong with other doctors — they’re just doing what they have to do,” Phipatanakul told MD Magazine. “There’s a lot of pressure to just get patients in, prescribe therapies, and keep things moving. I happen to know a lot about this all because it’s my field of interest and have funding for it.”
That said, she’s noticed the same concerns raised by Landrigan. Phipatanakul recalls having courses in biochemistry and similar fields in medical school, but not environmental health until her fellowship in allergy. She empathizes with educators pressured to focus on helping students pass their licensing tests.
Phipatankaul also said that, though they may not be able to intervene directly, physicians shouldn’t express a defeatist attitude about pollution to patients.
“I don’t think it does much good to say the air you breathe will kill you, and there’s not much you can do about it,” Phipatanakul said.
Phipatanakul preaches non-standard measures: though there’s no drug that reverses pollutant effects, there is greater research going into therapies that mimic its pathology. There’s also a greater emphasis on preventive measures, especially in the case of pediatric patients. Proven non-therapy measures have already started to make a difference.
“I think that there’s a lot of efforts being done to clean the environment,” Phipatanakul said. “We’re working on finding cleaner [energy] sources. We’ve been trying to save our environment with healthy, green housing. People are doing what they can and a lot of it is due to funding and advocates for the next generation.”
Forty-eight years ago, Barclay compared pollution to tuberculosis. He noted that, 70 years prior to his essay, the disease seemed insurmountable. But aggressive research, the strengthening of public health systems, and conglomeration among agencies eventually curbed the disease.
“It has taken 70 years of intensive cooperative effort on the part of the public and private agencies to control tuberculosis and to move within sight of eliminating it,” Barclay wrote. “We face a similar but much larger task with the diseases caused by environmental pollution.”
Phipatanakul already sees agencies like EPA and NIH not only addressing the problem, but doing so with a growing network of helpers and advocates. She encourages the public to join these networks: supporting the agencies eventually supports clinical developments.
“I think there’s enough people that, when they’re passionate about it, it’s great work,” Phipatanakul said. “NIH and EPA should continue to be supported to help clear pollutants. We need to be supportive of partnerships between people and researchers like me.”
Landrigan believes physicians could even play a greater role in the community’s efforts to improve the environment, citing the work of outspoken California-based researchers who eventually influenced statewide regulatory reform to combat pollution.
“Doctors are held in quite high esteem and when they speak up, especially collectively and say this is a problem, legislators listen,” Landrigan said. “When they hear from doctors about them having more kids in an emergency room due to asthma, they react.”
Environmental intervention may be beyond the realm of what clinicians were specifically taught, but Landrigan is still asking physicians to do what they practice: diagnose and treat.
“I make a plea for doctors to be alert that environmental effects may be causing disease in their patients, and I make a plea they advocate for new policies and practices to improve their patients’ health,” Landrigan said.