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Climate Change Calls For A New Hippocratic Oath

by Gary Cohen

During the COVID-19 crisis, the health care sector has stood at the epicenter of our collective trauma. In addition to taking care of people sickened by the virus, health professionals have served as messengers and truth tellers, providing the credible information Americans need to protect themselves. Health leaders have also shaped policy in real time that aimed to reduce the public health damage of the spreading virus.

You could say COVID-19 has been a dress rehearsal for an even larger crisis: climate change. Here, too, health professionals are at the center of community response and resilience. Given this pivotal role, it is time to reconsider the roles and responsibilities of health care providers. It is time, in short, for a new Hippocratic Oath. We must ask: What does it mean to “do no harm” in a world threatened by climate change?

Climate change is many things: a drain on our economy, a driver of global migration, a national security threat. It is also the greatest health threat we face today.

Fossil fuel combustion is heating up the planet, triggering more superstorms, killer heat waves, and infectious disease outbreaks. And air pollution from burning fossil fuels is also one of the leading causes of illness and premature death in the United States and globally. According to a recent report from the Harvard School of Public Health, in 2018, eight million people worldwide died prematurely from pollution caused by the burning of fossil fuels — far more than AIDS, malaria, and tuberculosis combined.

All of these impacts are likely to increase in frequency, intensity, and geographic range in the decades to come — with dire effects on public health. Indeed, between 2030 and 2050, climate change is likely to cause some 250,000 additional deaths each year.

Fossil fuel combustion exacts an economic, as well as human, toll. For example, the health costs of air pollution and climate change already far exceed $800 billion per year in the United States, a number that is likely to grow exponentially over this century.

And, like COVID-19, climate change is a force multiplier for the social, racial, and economic disparities that disfigure our society. Weather disasters are increasing in frequency and severity across the country, and low-income communities and people of color are hit hardest. Climate impacts are layered on top of preexisting conditions — such as high rates of asthma and diabetes — in vulnerable communities, leading to worse health outcomes. Moreover, polluting factories, waste dumps, and diesel truck routes are more likely to be sited in communities of color. Even the amount of tree cover to mitigate the heat island effect is less in Black and Brown communities — so the rate of heat-related deaths among Black people is up to 200 percent greater than for non-Hispanic whites.

In a warming, unequal world, it is impossible to tend to patients’ health without addressing the larger environmental and social context — just as it would be absurd to ignore a raging pandemic. That is why physicians are increasingly speaking out in favor of measures to tackle climate change. Doctors are reframing the climate crisis to focus on people’s health — a narrative to which people across the political spectrum can relate.

And the health sector as a whole has begun to leverage its power to bend the curve of greenhouse gas emissions. This is key because the sector represents almost 20 percent of the US economy, and a tenth of emissions. Globally, if the health sector were a country, it would be the fifth-largest emitter of greenhouse gases. So, by decarbonizing the health care sector, we can immediately improve the health of Americans, reduce diseases, and slash health care costs.

This work is well under way. Members of US Health Care Climate Council — a program of Health Care Without Harm, with representation from 18 health systems in 34 states — are reducing their carbon footprints and preparing their communities for the impacts of climate change. For example, a number of systems are supporting home weatherization programs that can reduce fossil fuel use, reduce environmental exposures in low-income homes, and reduce residents’ energy bills to free up money for other essential expenses such as food and medicines.

They are also making progress in transitioning away from fossil fuels for their energy needs. As of 2019, Health Care Climate Council members collectively produced or purchased more than one million megawatt hours of renewable energy each year. Cleveland Clinic, a member of the Health Care Climate Council with facilities in multiple states, has cut energy use intensity by nearly a third since 2010, while serving more patients than ever.

At the same time, the health sector is harnessing the enormous clout of hospitals and insurers to drive innovation and transform markets. Some health systems are using their purchasing power to support the transition to renewable energy, sustainable food systems, and a circular economy. Others are “buying local” to diversify supply chains and support economic health and wealth in the communities they serve. Twelve health systems recently announced their participation in an Impact Purchasing Commitment that requires them to double their racial diversity spend over the next five years, increase their local purchasing, and choose from a number of other strategies to reduce their climate footprint and detox their supply chain.

The past year vividly illustrated the essential role of health care workers and systems. It also showed, yet again, that our health as individuals cannot be divorced from the larger context — whether that is a pandemic, poverty, or a rapidly warming planet. Indeed, it’s estimated that just 10 percent to 20 percent of health depends on clinical care; the rest is derived from “social determinants of health” such as income, racial disparities, and the environment.

The health care sector occupies a unique position in US society both as an economic behemoth and as a profession with an ethical commitment to “do no harm.” That power and purpose can be leveraged to take on the twin crises of climate change and inequity.

To that end, we must expand the health sector’s mission beyond patient care, to include healing communities and the planet. This is the new social contract between the health sector and the communities they serve. This is the new Hippocratic Oath.

Author’s Note

The author is co-founder and president of Health Care Without Harm, created in 1996 to help transform the health care sector to be environmentally sustainable and support the health and climate resilience of the communities they serve.

Gary Cohen has been a pioneer in the environmental health movement for more than 35 years. He has helped build coalitions and networks globally to address health impacts related to climate change and toxic chemical exposure. Cohen is co-founder and president of Health Care Without Harm, created in 1996 to help transform the health care sector to be environmentally sustainable and support the health and climate resilience of the communities they serve. Since its inception, the nonprofit has grown to lead and partner in groundbreaking initiatives in more than 72 countries.

Cohen was awarded the Champion of Change Award for Climate Change and Public Health by the White House in 2013. In 2015, Cohen received a MacArthur Fellowship and a Genius Grant from the MacArthur Foundation.

This article was published in collaboration with the Island Press Urban Resilience Project, which is supported by The Kresge Foundation and The JPB Foundation. It was originally published July 14, 2021 on Health Affairs.

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A changing climate means a changing society. The Island Press Urban Resilience Project (URP) is committed to a greener, fairer future.