The U.S. Environmental Protection Agency is reportedly planning to revoke its 2009 declaration that greenhouse gas emissions are harmful to human health—known as the endangerment finding.

University of Michigan experts are available to comment on this potential move as well as its impacts on society, the environment, business and more.

Andy Hoffman is the Holcim (US) Professor of Sustainable Enterprise, a position that holds joint appointments at the Ross School of Business and School for Environment and Sustainability.

“The EPA’s decision to rescind the endangerment finding on climate change is, in effect, saying that climate change is not a threat,” Hoffman said. “We can deny that threat, but the insurance industry most certainly is not, with increasing storm frequency and severity leading to rising property insurance rates, reduced coverage, increased deductibles, more exclusions and, at the extreme, complete withdrawal from certain markets.

“The EPA decision reminds me of a statement attributed to Galileo when forced to recant his belief that the Earth revolves around the sun: ‘Eppur si muove,’ meaning ‘And yet it moves.’ The Trump Administration can deny the reality and the threat of a changing climate, but that does not change the fact that it still changes.”

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Richard Rood, professor emeritus of climate and space sciences and engineering, can comment on the intersection of science and policy.

“This is a large step in the persistent and consistent efforts over many years to dismantle the policy, the legal foundation, the infrastructure and the institutions of climate change science and policy,” Rood said. “This occurs simultaneously with the removal of the climate change chapter from the ‘Reference Manual on Scientific Evidence,’ used by federal judges. Where possible, we are eliminating climate change from the federal portfolio.”

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Ann Jeffers is an associate professor of civil and environmental engineering whose research focuses on fire safety engineering and how structures react to extreme load events such as wildfires.

“Removing restrictions on carbon emissions will only exacerbate climate-related disasters. If you think America has a wildfire problem now, just wait,” Jeffers said. “Carbon emissions are known to be the leading cause of climate change, which has produced a hotter, drier climate in North America. This, in turn, has resulted in more frequent and more intense wildfires than we have previously seen, resulting in catastrophic events like the Los Angeles fires in 2025, which resulted in thousands of structures burned and billions of dollars in losses.”

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Liesl Eichler Clark, U-M’s first director of climate action engagement, leads a new initiative aimed at linking the university’s expanding sustainability research, collaborations and engagement with external partners to accelerate climate action across the state of Michigan and beyond.

Previously, Clark served as director of the Michigan Department of Environment, Great Lakes, and Energy. She is an entrepreneur in the clean energy and sustainability space and co-founded the clean energy consulting firm 5 Lakes Energy. She was instrumental in the creation of the Michigan Energy Innovation Business Council and served as its president.

“Americans are suffering on a daily basis from our changing climate—from devastating floods to hurricanes to the now-commonplace challenge of wildfires—to name just a few of the harms,” Clark said. “Climate change is causing loss of human life and property and harming human health. Abandoning our collective national efforts to combat climate change through rescinding U.S. EPA’s ‘endangerment finding’ is short-sighted, terrifying and detrimental to the well-being of every human on this planet.

“Michigan is making progress on limiting our CO2 emissions in a cost-effective way that makes life better for Michiganders, led by the MI Healthy Climate Plan roadmap, relying on clean energy solutions that are often cheaper and easier to use. Clean energy jobs in Michigan continue to grow and our clean economy expands. We will continue to lead.”

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Alexander Rodriguez is an assistant professor of computer science and engineering who develops deep-learning models to better predict heat-related deaths. He can comment on how heat wave forecasting may need to change in the future.

“Heat waves are a major contributor to deaths in urban areas. Last year, heat waves resulted in an estimated 24,400 deaths, and over two-thirds of the deaths were linked to climate change. Another European heat wave resulted in over 40,000 deaths in 2003,” Rodriguez said. “Several studies suggest that we are heading toward a future in which heat waves will become more frequent and severe, and the move to rescind the EPA’s endangerment finding indicates that there will be less efforts to alleviate those trends.

“It is evident that we will need more forecasting systems, and significant improvements to them. Current methods focus primarily on meteorological data, but we can better predict the danger of heat waves by incorporating a range of other social and environmental factors that can make them lethal.”

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Parth Vaishnav is an assistant professor of sustainable systems. His research is focused on environmental and human health consequences of energy production and use, and his team works to find strategies to decarbonize the economy and to make climate mitigation and adaptation equitable.

“Climate change poses a risk to human health and is caused primarily by the emissions of greenhouse gases, the most important of which is carbon dioxide,” Vaishnav said. “The Clean Air Acts were promulgated to control air pollution that poses risks to human health. So, it seems logical that the endangerment finding should stand.”

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Tom Luben, senior research scientist in epidemiology, spent nearly 20 years in the EPA’s Office of Research and Development focusing on air pollution epidemiology, including evaluating, integrating and synthesizing evidence to support decision-making related to National Ambient Air Quality Standards.

“The endangerment finding is critical to protecting the public health and welfare of the American people. It is based on extensive and indisputable scientific evidence and the consensus of global experts,” Luben said. “Any effort to repeal or diminish the endangerment finding will harm the health and well-being of Americans.”

In an era in which the toll of climate change plays out regularly, he said undoing protections “would threaten the health of millions of Americans.”

“Increases in ground-level ozone concentrations associated with climate change cause respiratory health problems ranging from decreased lung function and asthma exacerbations to increased emergency department visits and hospital admissions,” Luben said. “Certain parts of the population are especially vulnerable to these effects, including children, older adults, pregnant people and individuals with preexisting health conditions. In addition to increased air pollution, the proliferation of extremely hot days, floods, storms, drought and fires linked to a changing climate will impact the health of everyone.”

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Nina Mendelson, the Joseph L. Sax Collegiate Professor of Law, teaches and conducts research in the areas of administrative law, environmental law, statutory interpretation and the legislative process. She can provide more context once the language of the repeal is available.

“An EPA move now to repeal its 2009 endangerment finding both could be devastating to our efforts to address climate change and would face immediate court challenges,” Mendelson said. “A repeal would be vulnerable in the courts on both factual and legal grounds, because the evidence on climate change has strengthened since 2009, and because the EPA would have to provide the courts with some very good reasons for disagreeing now with a decision that has been in place for over 15 years.”

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Rachel Rothschild is an assistant professor of law. Her scholarship sits at the intersection of environmental law, history and policy. She can provide more context once the language of the repeal is available.

“An EPA repeal of the 2009 endangerment finding is at odds with Supreme Court precedent as well as scientific research on the harms from climate change,” Rothschild said. “While EPA will almost certainly face a legal challenge over its repeal of the endangerment finding, that litigation will take time at a moment when we have little runway left to avoid extremely serious effects from a warming world.

“In the absence of federal government regulations, it will be even more important for states to continue making progress on reducing greenhouse gas emissions, promoting clean energy, and ensuring fossil fuel companies pay their fair share of the costs for climate adaptation.”

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Brian McCullough, associate professor of kinesiology, studies the environmental impacts of the sport sector, sport spectator environmental behaviors and attitudes, environmental messaging and narrative for internal and external stakeholders, and fan engagement with a sport organization’s sustainability initiatives.

“This action eliminated one of the primary incentives for legal and legislative pressure on sport organizations, venues and event organizers to actively consider their environmental impacts,” McCullough said. “Despite this change, environmental waste continues to represent economic waste. Organizations, both within and outside the sport sector, can still pursue efficiencies that yield economic, social and environmental benefits.

“However, I am concerned that the necessary supporting infrastructure may not be maintained to sustain the recent momentum toward greater environmental responsibility in the sport sector.”

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Gregory Keoleian is a professor of environment and sustainability and of civil and environmental engineering, and co-founder/co-director of the Center for Sustainable Systems, as well as co-director of MI Hydrogen, U-M’s hydrogen initiative. He develops life-cycle models to analyze decarbonization pathways and accelerate sustainability solutions for clean energy transitions, alternative vehicle technologies, buildings and infrastructure, and food systems. He can speak to the administration’s actions that slow and reverse climate and sustainability progress in automotive, energy and more.

“Denying the science would be reckless and irresponsible. In 2009, the EPA issued its science-based finding that the buildup of heat-trapping greenhouse gases in the atmosphere endangers public health and welfare,” Keoleian said. “The endangerment finding requires the EPA to take action to reduce greenhouse gas emissions generated from vehicles, power plants and other industrial sources.

“The administration’s proposed action would set back industry investment, hurt U.S. economic competitiveness, take away clean energy jobs, reverse decarbonization progress and will ultimately result in greater climate change related damages and costs to society—for example, from flooding, wildfires, droughts, insurance risks, human health effects. The magnitude of the disruption caused would be devastating for business and industry, government agencies, communities and individuals with future generations most severely impacted. Disregarding climate pollution, one of the most critical threats to humanity, would further isolate the United States from the rest of the world. Nobody wins from this action; we lose in countless ways.”

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Jonathan Overpeck, an interdisciplinary climate scientist and dean of the School for Environment and Sustainability, is an expert on climate and weather extremes, sea-level rise, the impacts of climate change and options for dealing with it. He served as a lead author on the authoritative Intergovernmental Panel on Climate Change 2007 and 2014 reports.

“I worked with a team of fellow climate scientists who weighed in as experts on the original endangerment finding almost 20 years ago to publish an updated paper recently highlighting that the scientific evidence has only become much stronger that climate change is endangering human health and welfare—and much more,” Overpeck said.

“Climate change and its impacts are accelerating and are impacting lives and livelihoods in the U.S. more than ever. Climate change is supercharging extreme heat, drought, wildfires, extreme rainfall, flooding, sea level rise and challenges to human health in the U.S. and around the globe.”