air-pollution – Learning, Science and Society

We’ve written a lot about air pollution over the years (LSS passim) Mainly to say that air pollution, particularly in the form of PM_2.5 particles can do all sorts of harm to your lungs and circulatory systems. A fact well-attested by some of the sharpest medical minds on the planet as this WHO report shows[1] But now there is increasing evidence that these pesky particles may play a big part in the massive wave of dementia and neurodegenerative disease that is sweeping across the world. The latest evidence is summarised by Professor Eef Hogervorst for The Conversation.[2] And it’s pretty grim.

Air pollution and the deadly particles it chucks out are associated with all kinds of activities beloved of certain US politicians and their followers. Fossil fuels; road transport; old style heavy industries; good ol’ boys roun’ the barbecue fire, and that sort of thing. But how do you measure it, and separate out other plausible causes? A rather nifty US study started by mapping Medicare claims for dementia by postcode and PM _2.5 particle density. Other factors such as smoking, bad diets and poverty were also considered. The latter was admirably controlled by factoring in Medicaid eligibility, a sure indicator of low wealthin the US. We often use the phrase Killer Quote here: this time it’s more than a rhetorical flourish

…….pollution levels in the areas studied were, on average, about twice as high as the limit set by the World Health Organization (WHO). ………..The researchers found that the increased Alzheimer’s risk in polluted areas remained even after taking high blood pressure, stroke and depression into account

Eef goes on to explain how and why PMs are pulverising your grey matter: but click on! For she does it much better than we ever could.

And our thoughts, gentle readers? Firstly, the work confirms other reports we’ve noticed [3] Secondly the impressive size of the sample. Above all the careful attempts to control other factors such as diet and poverty; we know you prefer thoughtful scholarship over blind jumping to conclusions. Nothing is yet conclusive: but the hypothesis that air pollution causes other forms of dementia fits the available data so very much more closely than anything else does seems to us to be as close to one as you can get.

[1] WHO global air quality guidelines: particulate matter (‎PM2.5 and PM10)‎, ozone, nitrogen dioxide, sulfur dioxide and carbon monoxide

[2] https://theconversation.com/air-pollution-may-directly-contribute-to-alzheimers-disease-new-study-275873?utm_medium=email&utm_campaign=Latest%20from%20The%2%5B2%5D

[3] The effect of ambient air pollution (PM2.5) on dementia risk | Nature Aging

#air pollution #fossil fuels #smoke #alzheimers #dementia #WHO #health #medicine

We do quite a lot of pollution stories here. Too much carbon dioxide and methane are wrecking the climate. Too much sewage is turning the seas toxic. But there’s one area we haven’t covered enough. The effect of air pollution directly on our lungs. According to the latest report from the UK Government (which, after 14 years of Conservative rule can hardly be a bastion of woke tofu-eating commie liberals):

Epidemiological studies have shown that long-term exposure to air pollution (over years or lifetimes) reduces life expectancy, mainly due to cardiovascular and respiratory diseases and lung cancer. Short-term exposure (over hours or days) to elevated levels of air pollution can also cause a range of health impacts, including effects on lung function, exacerbation of asthma, increases in respiratory and cardiovascular hospital admissions and mortality.[1]

It is estimated that air pollution in the UK may be causing up to 36000 excess deaths per year.

The combined effects of all those cars, lorries, aeroplanes, factories, fossil fuel power stations and goodness-knows-what-else, produce quite a cocktail of potentially deadly things for us to breathe. But most experts agree that the Two Big Killers are particulate matter, the so-called PM_n series and nitrates, mainly NO₂. But which is worse? If we got rid of PM_2.5 for example, would the NO₂ still be murdering us? An ingenious study by Joshua Bateman and Martin Clift, reported in the Conversation, seems to suggest an answer. The researchers have created laboratory models of the alveolar epithelium, the key tissue of the human lung which interacts with the atmosphere. For the first time it was possible to expose these cells to different levels of pollutants, both singly and together.

The results suggest the Two Big Killers are at their worst when they act together. And this has a important implications in the struggle for clean air. Just like early attempts to reduce smoking, attempts to clean up the air have run into enormous resistance, which can be bolstered by generous funding from various interest groups which seem to have little interest in clean air. Might it be possible to concentrate first on reducing one of the Big Two Killers first? That would not save as many lives as eliminating both. But it is a much more achievable, and feasible, start.

[1]https://www.gov.uk/government/publications/health-matters-air-pollution/health-matters-air-pollution

[2]https://theconversation.com/air-pollution-we-recreated-the-deepest-sections-of-your-lung-in-a-laboratory-to-understand-how-polluted-air-can-affect-your-health-2220

#nitrates #particulate matter #air pollution #cancer #cardio vascular disease

Tag: air-pollution

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