Study shows air pollution may be causing cognitive decline in people

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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.

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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.

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Citation: Study shows air pollution may be causing cognitive decline in people (2018, August 28) retrieved 18 October 2019 from
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Aug 28, 2018
That is evident in the Midwest, Trump Country.

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)

Aug 28, 2018
The use of electric vehicles should end that.

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.

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.

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.

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.

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