Almost as if they wanted to create more Fox News viewers.
The air in New York City has gotten a lot cleaner over the past few decades, and children are smarter for it.
That’s according to a recent study published by researchers at Columbia University who followed more than a thousand children between 1998 and 2020, testing their cognitive development from around age 1 until they turned 3.
During that period, clean air and climate policies substantially reduced local air pollutants like nitrogen dioxide and the fine particulate matter known as PM2.5. When mothers breathed cleaner air during pregnancy, their toddlers’ scores on mental development tests later trended upward.
As city policies limiting pollution from vehicles and buildings took effect between 1998 and 2016, local concentrations of PM2.5 fell by about 32 percent. Nitrogen dioxide, which worsens conditions like asthma, followed a similar trend. When air quality improved, so did toddlers’ cognitive development: At 3, the group of children born most recently averaged about 26 percent higher on a benchmarking test than the children born before climate rules took effect.
Not all that improvement can be attributed to better air quality. But even after adjusting for factors like parental age, education levels and the presence of smokers in the household, the results showed a significant relationship between air quality and cognitive development in early childhood.
“This long-term, community-based research has generated new evidence that policies to clean the air and address climate change are beneficial to children’s brains,” said Frederica Perera, a special research scientist and professor emerita at Columbia University Mailman School of Public Health, who led the study.
It can be difficult to measure local health effects of reducing greenhouse gas emissions, Dr. Perera said, and that makes it challenging to link regional climate policies directly with positive health outcomes. But by studying pollutants that are emitted from smokestacks and tailpipes alongside planet-warming carbon, researchers are making the case that climate policies can have measurable effects on human health.
A study that came out last month, for example, found that a strict anti-traffic policy rolled out in London in 2019 resulted in improved lung health for children living within a low-emissions zone.
Similar zones in Paris and Sweden have been linked to lower childhood asthma rates, as has a congestion-pricing policy in Stockholm. (New York City’s own congestion-pricing policy, which charges drivers a fee for entering parts of Manhattan, has not had much of an impact on air quality. This is not entirely bad news: Many feared the measure would send more truck traffic into the Bronx, worsening pollution there.)
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Below, National Institute of Health shows a link between demential and wildfire smoke, in particular.
Exposure to a type of air pollution called fine particulate matter, or PM2.5, has recently been identified as a potential risk factor for dementia. The reason for the connection is not yet well understood. Researchers do know that fine particulates can affect the lungs, circulate in the blood, and move into the brain where they might be able to cause direct damage.
But there are many sources of fine particulate matter, and it hasn’t been clear whether PM2.5 pollution from some sources pose greater risks than others. Particulates from various sources, such as traffic, agriculture, and smoke, can be physically and chemically different.
An NIH-funded study led by Drs. Boya Zhang and Sara Adar from the University of Michigan examined the links between different types of PM2.5 air pollution and dementia. They looked at data from more than 27,000 adults aged 50 and older in the Health and Retirement Study, an ongoing national study of aging, collected between 1992 and 2016. As part of the study, participants underwent cognitive testing every two years or had caretakers report on their memory and cognitive function. The mean period of follow-up was 10.2 years. The average age of participants was 60.
Exposure to a type of air pollution called fine particulate matter, or PM2.5, has recently been identified as a potential risk factor for dementia. The reason for the connection is not yet well understood. Researchers do know that fine particulates can affect the lungs, circulate in the blood, and move into the brain where they might be able to cause direct damage.
But there are many sources of fine particulate matter, and it hasn’t been clear whether PM2.5 pollution from some sources pose greater risks than others. Particulates from various sources, such as traffic, agriculture, and smoke, can be physically and chemically different.
An NIH-funded study led by Drs. Boya Zhang and Sara Adar from the University of Michigan examined the links between different types of PM2.5 air pollution and dementia. They looked at data from more than 27,000 adults aged 50 and older in the Health and Retirement Study, an ongoing national study of aging, collected between 1992 and 2016. As part of the study, participants underwent cognitive testing every two years or had caretakers report on their memory and cognitive function. The mean period of follow-up was 10.2 years. The average age of participants was 60.
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American Parkinson Disease Association:
A major scientific study has uncovered compelling evidence that air pollution may directly increase the risk of Lewy body dementia (LBD), a group of diseases that includes Parkinson’s disease dementia (PDD) and Dementia with Lewy bodies (DLB). Previous studies have linked poor air quality to general cognitive decline, but many gaps still exist in delineating the connection between the two. This recent study, published in Science on September 4, 2025, is one of the first studies to focus specifically on LBD, which is characterized by the abnormal buildup of a protein called alpha-synuclein in the thinking parts of the brain.
This study suggests that air pollution is a major public health concern that may contribute to the development of LBD. PM2.5 can be reduced and/or limited by the use of cleaner energy sources, tighter emissions standards, and personal choices like indoor air filtration.