Study shows air pollution may be causing cognitive decline in people

August 28, 2018 by Bob Yirka, Medical Xpress report
Credit: CC0 Public Domain

A trio of researchers from Beijing Normal University, Yale University and Peking University has found a link between air pollution and human cognitive decline. In their paper published in Proceedings of the National Academy of Sciences, Xin Zhang, Xi Chen, and Xiaobo Zhang outline their study and what they found.

Most everyone knows that can cause physical ailments, particularly those associated with the lungs, but new evidence suggests it can also cause mental harm. In this new effort, the researchers have built on the findings of other studies that have suggested air can cause cognitive decline.

The study by the trio consisted of carrying out math and verbal testing of 25,000 people living in 162 counties in China and then comparing those results with air pollution conditions. The researchers noted that the tests were given to people of both genders from teens to geriatrics.

In looking at their results the researchers report finding that the higher the levels of pollution the lower the test scores as people grew older. They note that the biggest impact was on males, especially those with less education. The researchers suggest this was likely because less educated men work outside more in China and are thus more exposed to . They note also that the fact that the decline was seen as progressive over time is a strong indicator of air pollution being the cause, rather than other sources. They suggest their findings offer additional evidence of long-term exposure to air pollution causing a decline in cognitive abilities. They note also that they found some evidence of an increase in the rate of neurodegenerative diseases.

The researchers acknowledge that they do not know how pollution might be causing , but suggest it might have some impact on white matter in the brain, considering the role it plays in coordinating communications between brain regions. Also, it is not clear which air pollution constituent might be to blame. In their study, the researchers tested only for nitrogen, sulfur dioxide and particulates smaller than 10 micrometers in diameter. That left out a whole segment of possibilities including carbon monoxide, ozone and larger particulate matter.

Explore further: Study finds association between air pollution and cognitive decline in women

More information: Xin Zhang et al. The impact of exposure to air pollution on cognitive performance, Proceedings of the National Academy of Sciences (2018). DOI: 10.1073/pnas.1809474115

This paper examines the effect of both cumulative and transitory exposures to air pollution for the same individuals over time on cognitive performance by matching a nationally representative longitudinal survey and air quality data in China according to the exact time and geographic locations of the cognitive tests. We find that long-term exposure to air pollution impedes cognitive performance in verbal and math tests. We provide evidence that the effect of air pollution on verbal tests becomes more pronounced as people age, especially for men and the less educated. The damage on the aging brain by air pollution likely imposes substantial health and economic costs, considering that cognitive functioning is critical for the elderly for both running daily errands and making high-stake decisions.

Related Stories

Study finds association between air pollution and cognitive decline in women

February 13, 2012
A large, prospective study led by a researcher at Rush University Medical Center indicates that chronic exposure to particulate air pollution may accelerate cognitive decline in older adults. The results of the study will ...

Living in greener neighborhoods is associated with slower cognitive decline in elderly

July 12, 2018
Contact with green space is known to have beneficial effects for mental health. A new study by the Barcelona Institute for Global Health (ISGlobal), a centre supported by the "la Caixa" Foundation, suggests that it may also ...

Air pollution leads to cardiovascular diseases

August 23, 2018
Air pollution, and fine dust in particular, is responsible for more than four million deaths each year. Almost 60 per cent of deaths occur as a result of cardiovascular diseases. Scientists around Professor Thomas Münzel, ...

Air pollution may contribute to white matter loss in the brain

June 15, 2015
In a new study, older women who lived in places with higher air pollution had significantly reduced white matter in the brain. For the study, a research team took brain MRIs of 1403 women who were 71 to 89 years old and used ...

Prolonged exposure to air pollution leads to genetic changes in rat brains, study finds

May 8, 2018
Prolonged exposure to particulate matter in air pollution in the Los Angeles Basin triggered inflammation and the appearance of cancer-related genes in the brains of rats, a Cedars-Sinai study has found.

Study suggests air pollution breathed in the months before and after conception increases chance of birth defects

January 8, 2018
A team of researchers with the University of Cincinnati and Cincinnati Children's Hospital has found evidence that indicates that pre-and post-pregnant women living in an area with air pollution are at an increased risk of ...

Recommended for you

US paves way to get 'lab meat' on plates

November 17, 2018
US authorities on Friday agreed on how to regulate food products cultured from animal cells—paving the way to get so-called "lab meat" on American plates.

Youth dating violence shaped by parents' conflict-handling views, study finds

November 16, 2018
Parents who talk to their children about nonviolent ways of resolving conflict may reduce children's likelihood of physically or psychologically abusing their dating partners later—even when parents give contradictory messages ...

A low-gluten, high-fiber diet may be healthier than gluten-free

November 16, 2018
When healthy people eat a low-gluten and fibre-rich diet compared with a high-gluten diet, they experience less intestinal discomfort including less bloating. Researchers at University of Copenhagen show that this is due ...

Why we shouldn't like coffee, but we do

November 15, 2018
Why do we like the bitter taste of coffee? Bitterness evolved as a natural warning system to protect the body from harmful substances. By evolutionary logic, we should want to spit it out.

Dietary fat is good? Dietary fat is bad? Coming to consensus

November 15, 2018
Which is better, a low-fat/high-carbohydrate diet or a high-fat/low-carbohydrate diet—or is it the type of fat that matters? In a new paper featured on the cover of Science magazine's special issue on nutrition, researchers ...

Survey reveals how we use music as a possible sleep aid

November 14, 2018
Many individuals use music in the hope that it fights sleep difficulties, according to a study published November 14 in the open-access journal PLOS ONE by Tabitha Trahan of the University of Sheffield, UK, and colleagues. ...


Adjust slider to filter visible comments by rank

Display comments: newest first

3 / 5 (2) Aug 28, 2018
That is evident in the Midwest, Trump Country.
5 / 5 (1) Aug 28, 2018
If you think this only affects people in China, try reading this study of a large cohort of 4.4 million Canadians (Canadian-born, >5 yrs old) living in Ontario Canada. The interpretation from that study: In this large population-based cohort, living close to heavy traffic was associated with a higher incidence of dementia, but not with Parkinson's disease or multiple sclerosis.

Living near major roads and the incidence of dementia, Parkinson's disease, and multiple sclerosis: a population-based cohort study by Chen et al. (2017)
5 / 5 (1) Aug 28, 2018
The use of electric vehicles should end that.
5 / 5 (1) Aug 28, 2018
Recall the famous study of zoo animals that led to the elimination of leaded gasoline. We are so fragile and we treat each other so harshly. Do not think for one moment that science does not know the effects of long term low dose carbon dioxide on human intelligence. But over and over again science bows to economic power.
1 / 5 (1) Aug 28, 2018
There has been no change in human health or IQ since leaded gasoline was eliminated.
This study didn't measure things like carbon monoxide that the hemoglobin in our blood bonds to 300 times better than it does oxygen.
Nowhere does this study implicate CO2.
Exhaled CO2 is about 4.5%, CO2 in atmosphere is about 0.04%. > two orders of magnitude difference.
China is getting 62% of its electricity from coal plants and building many more, not just in China but all over the world.
Electric cars in China will have minimal effect on particulate pollution since most of the older plants don't have scrubbers and the newer plants leave them off to reduce costs.
5 / 5 (1) Aug 28, 2018
That article in the referenced blog from tbp is four years old. They have shut down every coal plant in Beijing, and are the world's biggest developers of renewables.

Time to get some news.
5 / 5 (1) Aug 28, 2018
It may also correlate with low o2 levels.

The deepest parts of Tokyo, supposedly, have the odd o2 station, due to the o2 levels being so low they cause people to pass out.

That article in the referenced blog from tbp is four years old. They have shut down every coal plant in Beijing, and are the world's biggest developers of renewables.

Time to get some news.

exactly. they will probably fly right by the west, specifically the USA, as we can't get the greedy small minded psychopathic parasites of the swamp ---off of us.

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.