Less soot benefits our health and economy. The EPA should take action.

If reducing air pollution can cut dementia cases by 15 percent and delay age-related cognitive decline by a year or two for every senior citizen — as the science suggests it would — the U.S. would see substantial economic savings from the EPA’s tougher standards.

Any day now, the Environmental Protection Agency is expected to announce tougher standards to limit soot — the tiny particles of pollution that waft through the air from sources as diverse as power plants, wood-burning stoves, wildfires and car exhaust. 

The business community is fighting hard to weaken the regulations. The National Manufacturing Association blitzed D.C. airwaves last month with a TV ad claiming that tougher standards would restrict growth. The U.S. Chamber of Commerce argues that the rule would have “profound impacts economy-wide.” 

But they’re missing the bigger picture. The pollutants the EPA seeks to clean up are highly dangerous to our health. And the economic burden caused by failing to tighten regulation far outstrips the potential adverse impact of tougher standards. 

Let’s consider just one of the many health problems associated with soot: Dementia. 

Air pollution is strongly linked to cognitive decline. Numerous studies of both long-term and short-term exposure to pollutants have found a significant impact on cognition, especially among older adults.  

The most dangerous pollutants for human health are the smallest particles, known as PM 2.5 because they’re less than 2.5 micrometers in diameter. (For comparison, the average diameter of a strand of human hair is about 50 micrometers.) These particles can lodge deep in the lungs and enter the bloodstream and the brain, damaging cerebral blood vessels. 

Multiple studies have demonstrated a link between long-term exposure to these microscopic pollutants and accelerated cognitive decline, including the development of Alzheimer’s disease. In 2020, the Lancet Commission listed air pollution as one of 12 modifiable risk factors for dementia.  

The key word there is “modifiable” — because pollution is not inevitable, and evidence-based policy can dramatically reduce the risk of cognitive damage. 

With these data in mind, let’s return to the EPA’s proposed updates to the National Ambient Air Quality Standards. The standards currently stipulate that outdoor air should have no more than 12 micrograms of PM 2.5 pollutants per cubic meter. The EPA is considering lowering that threshold to anywhere from 8 to 11 micrograms per cubic meter. Adopting a threshold at the lower end of that range — a bolder and more protective standard — would yield enormous benefits. 

This isn’t speculation. We know it will work. A large study of older women across multiple cities in the U.S. found that cutting their exposure to PM 2.5 pollution over a decade cut their risk of dementia by 14 percent. A similar study in France, also published last year, corroborated those findings, calculating that cleaner air led to a 15 percent reduction in dementia risk. 

Yet another recent U.S. study followed more than 2,200 older women for two decades and found that those who lived in areas where the air quality improved had slower age-related cognitive decline than their peers. In places that reduced ambient pollution the most, cognitive decline was delayed by up to 1.6 years. 

The reduction in human suffering implied by those numbers should be evident — and reason enough to enact tougher soot standards. Since industry is making an economic case against regulation, it’s worth considering the science from a dollars-and-cents standpoint as well.  

Across the U.S., caring for people with dementia costs the nation $345 billion a year. In addition, more than 11 million Americans look after loved ones with dementia, which takes an enormous emotional and personal toll, including lost productivity. Those numbers are expected to soar as Baby Boomers age.  

If reducing air pollution can cut dementia cases by 15 percent and delay age-related cognitive decline by a year or two for every senior citizen — as the science suggests it would — the U.S. would see substantial economic savings from the EPA’s tougher standards. 

And it’s important to emphasize that dementia is just one of the many health harms linked to PM 2.5  pollution. There is a wealth of scientific data linking exposure to these noxious particles to heart attacks, strokes, asthma attacks, preterm births, bone fractures, chronic lung disease, and myriad other serious diseases. All these conditions cause tremendous human misery. All limit millions of people from reaching their full potential. And all exact a heavy economic burden, both on individual families and on taxpayer-funded programs such as Medicare and Medicaid. 

Tougher EPA regulations may indeed cause some short-term pain to some sectors of industry. But the benefits far outweigh those costs. 

One final study proves the point. Published last month in the journal Science, it found that air pollution from coal-fired power plants caused 460,000 deaths among the Medicare population in the U.S. from 1999 through 2020. That statistic showed up in a lot of headlines. But to me, the most notable finding was this: Annual deaths from these pollutants plunged by 95 percent over the two decades studied, as coal-fired plants either shut down or installed new emission control technology to meet EPA standards. 

The emergence of effective filters and scrubbers to control power plant emissions points to another clear benefit of regulation: It spurs innovation. Tougher soot standards will no doubt spark the development of new technology to help industry meet those standards. That innovation can, in and of itself, become an engine of economic growth. 

The bottom line: Smart regulation, firmly rooted in science, keeps our country moving forward. Enacting stronger soot standards will save lives. It will also reduce the economic burden of disease. We can’t afford to do anything less. 

Andrea Baccarelli, MD, Ph.D., is the incoming dean of the faculty at the Harvard T.H. Chan School of Public Health and the Leon Hess professor and chair of the Department of Environmental Health Sciences at Columbia Mailman School of Public Health.