Dr. Jodi Sherman wants to expand the medical profession’s understanding of patient safety far beyond the exam room and hospital bed. For Sherman, the oft-heard medical mantra of “first do no harm” should also push the health care system to do more to reduce its harmful air emissions and their impact on people’s health.
“Traditionally, our duty has been to the patient in front of us,” Sherman told me. “But we have a duty to protect society as well.”
Sherman, an assistant professor of anesthesiology at Yale School of Medicine, recently co-authored a new study on harmful air pollutants coming from the health care sector and their effect on public health. The study, published earlier this month in PLOS ONE, found that if the U.S. health care system were its own country, it would rank 13th in the whole world for greenhouse gas emissions, a major contributor to global warming. That ranking would put it ahead of the entire United Kingdom. The study also found that in 2013, the health care sector was responsible for significant portions of overall U.S. emissions and impacts, including 12 percent of acid rain, 10 percent of greenhouse gas emissions, 10 percent of smog formation, 9 percent of respiratory diseases from particulate matter, and 9 percent of criteria air pollutants, which include ground-level ozone, carbon monoxide and lead.
To measure the public health impact of such health care emissions, Sherman and her study co-author, Matthew Eckelman, an assistant professor of civil and environmental engineering at Northeastern University, used the disability-adjusted life year metric, or DALY, which measures disease burden via the number of years lost due to poor health, disability and premature mortality. They estimated that in 2013, the health care emissions measured in the study resulted in 470,000 DALYs lost due to pollution-related disease.
“Health care is such a large sector as a portion of the economy that we knew the contributions were going to be big,” Eckelman told me. “But we didn’t have a sense of the patterns or how large they would be.”
Sherman and Eckelman’s study isn’t the first to examine health care sector pollution. The first study to estimate the sector’s carbon footprint came out in 2009 and found that 8 percent of U.S. greenhouse gas emissions came from health care, with such emissions stemming directly from health care activities and purchases as well as indirectly through the sector’s supply chain. Sherman and Eckelman’s study updates that 2009 estimate using more recent data; it examines a wider range of health care-related air pollutants; and it’s the first to translate the pollution estimates into a commonly used public health measurement — DALYs.
Sherman and Eckelman write:
Hospitals are the second-most energy-intensive commercial buildings in the country, after food service facilities. Hospitals are typically large buildings, open 24 hours a day, seven days a week, and contain several energy-intensive activities, including sophisticated heating, cooling, and ventilation systems, computing, medical and laboratory equipment use, sterilization, refrigeration, laundry, as well as food service. In addition to energy used on site in the form of heating fuels and electricity, the health care system also uses vast quantities of energy-intensive goods and services, such as pharmaceuticals and medical devices, which require significant energy inputs for their manufacturing. As the U.S. is the second-largest emitter of greenhouse gases globally, it follows that the health care sector is an important target for emissions reductions as well.
To conduct the PLOS ONE study, the researchers used economic modeling and national health expenditure data to estimate emissions over a 10-year period, 2003-2013. The study found that the health care sector’s greenhouse gas emissions increased more than 30 percent in the last decade, representing nearly 10 percent of national totals in 2013. The majority of such emissions wasn’t directly from health care facilities, but associated with the sector’s suppliers of energy, goods and services, such as power generation and construction.
In regard to non-greenhouse gas emissions, power generation for the health care industry was the largest contributor to acidification, respiratory impacts and smog formation. The sector’s largest contributors to ozone depletion were surgical and medical instrument manufacturing as well as pharmaceutical preparation manufacturing, while the biggest contributors to ecotoxicity and human health toxicity were health care-related waste management and remediation.
Overall, the study found the 470,000 DALYs lost to health care-related emissions is in the “same order of magnitude” as deaths due to preventable medical errors.
Both Sherman and Eckelman said while there’s no way to get health care emissions to zero, there are ways to reduce the sector’s pollution. For example, Eckelman said many health care facilities produce their own power, as opposed to relying on outside energy suppliers. As such, he said studies such as his could help justify new energy management and efficiencies. In the day-to-day practice of medicine, Sherman said clinicians can play a key role in reducing waste, which in turn could help reduce emissions within the health care supply chain. For instance, changes in how medical supplies and services are used could conserve resources, reduce waste and curb upstream emissions.
“A critical knowledge gap exists in the medical community regarding the indirect health consequences of wasteful, non-value added practices in all their forms, making resource conservation education and leadership crucial to improving the health system,” the study stated.
The study also noted that a number of efforts are already underway to reduce health care-related pollution and the sector’s role in climate change. For example, Health Care Without Harm has programs around the world to help health care facilities reduce their environmental footprints; the U.S. Department of Energy’s Hospital Energy Alliance is helping facilities improve their energy efficiency; and Practice Greenhealth works toward sustainable health care. However, Sherman said the role of individual clinicians is often missing from such efforts.
“So many of the drivers behind this problem are related to clinical decision-making, so it’s critical that they see this issue as a new way of viewing patient safety,” she told me. “Until we get the clinical side of the equation activated, we are missing a big opportunity to make headway here.”
As for future research on the topic, Sherman and Eckelman plan to continue updating their estimates as well as conduct an international comparison of health care-related emissions. Sherman said she also hopes to better quantify excess anesthetic gases that escape during medical procedures — such vapors, considered greenhouse gases, are typically vented off hospital rooftops and weren’t included in the PLOS ONE study.
“We both hope this study helps justify and helps spur more engagement between hospitals and clinics and their supply chains,” Eckelman told me. “The health care sector can leverage its purchasing power to create change.”
For a full copy of the health care emissions study, visit PLOS ONE.
Kim Krisberg is a freelance public health writer living in Austin, Texas, and has been writing about public health for nearly 15 years.