Children's stunted lungs show recovery in ultra low emission zone
bbc.com
bbc.com
Delhi: 442. Lahore: 334. Beijing: 16. These are the levels of PM 2.5, one of the principle measures for air pollution, on November 19. How China cleaned up its air pollution – and what that meant for the climate: https://theconversation.com/how-china-cleaned-up-its-air-pol...
And yet they have the most coal plants, and the most coal plants under construction. This comparison includes India.
This is PM2.5 map of Beijing today: https://earth.nullschool.net/#2026/08/20/0200Z/particulates/...
This is London: https://earth.nullschool.net/#2026/08/20/0200Z/particulates/...
This is East USA: https://earth.nullschool.net/#2026/08/20/0200Z/particulates/...
They are not even close.
For the kicks, here is Delhi today: https://earth.nullschool.net/#2026/08/20/0200Z/particulates/...
Also lower than Beijing. (There's a hotspot to the west of Delhi due to wildfires.)
And if the trend of China cleaning up their electricity supply continues (they just slipped under 50% coal) then even existing EVs will get cleaner every year with less pollution created at distant powerplants.
They add coal power because it's super fast to build, but it's not a permanent solution.
https://chinadata.live/data/coal-consumption-china-vs-world/
https://en.wikipedia.org/wiki/Coal_reserves
We can look at more concrete promises by leadership of China:
"In a video statement to the UN in New York, President Xi Jinping said that China would reduce its greenhouse gas emissions across the economy by 7-10% by 2035, while "striving to do better"."
Too little, too late.
"Most scenarios to limit warming to 1.5C - or even well below 2C - would require China to make much greater cuts than that by 2035"
Well yeah, but not in Beijing
Indoor pollution ---> Use these for cooking (induction, electric resistance) stove, heatpump waterheater and furnace for HVAC
Would also be nice to do: stop using coal, gas power plants. These are usually farther out from cities and probably not the most urgent. (except when Elon Musk or new DCs decide to use gas turbines in cities).
Researchers say they have cracked how air pollution leads to cancer, in a discovery that completely transforms our understanding of how tumours arise: https://www.bbc.com/news/health-62797777 (discussion: https://news.ycombinator.com/item?id=32788706)
Surprise! Electric cars are already making California healthier (2023): https://electrek.co/2023/02/10/surprise-electric-cars-are-al...
Air Pollution Kills 10 Million People a Year. Why Do We Accept That as Normal? https://www.nytimes.com/2022/07/08/opinion/environment/air-p...
Tiny air pollutants may cause changes in brain structure that resemble those of Alzheimer’s disease: https://www.nytimes.com/2019/11/25/well/mind/air-pollution-b...
It is important to use metrics and language that people can understand. Cigarette smoking is very well known, because public health initiatives make sure the harm is labeled. Air Pollution and Cigarette Equivalence: https://berkeleyearth.wpengine.com/air-pollution-and-cigaret...
Delhi’s air pollution equivalent to smoking 50 cigarettes per day but experts say it can be fixed: https://epic.uchicago.in/delhis-air-pollution-equivalent-to-...
Almost all countries failing to meet mark for PM2.5, tiny particles expelled by vehicles and industry that can cause health problems: https://www.theguardian.com/environment/2024/mar/19/air-poll...
Bees struggle to find flowers because of air pollution: https://news.ycombinator.com/item?id=37434381
Cars and automobility have killed 60–80 million people since their invention. 1 in 34 deaths are caused by cars and automobility with 1,670,000 deaths per year. Car harm: https://news.ycombinator.com/item?id=39465354
Gas stoves pollute homes with benzene, which is linked to cancer: https://news.ycombinator.com/item?id=36364524
Amazon backs power plant that may become top source of US climate pollution: https://news.ycombinator.com/item?id=49249971
Per day, which for some reason the headline didn’t include. Two packs a day is a pretty terrible baseline. At least it’s not addictive.
depending on where you live, its really hard to motivate to take part in generating less polition due to the involved costs and living costs already being too high
However what you don't talk about is how much progress as been possible thanks to cars. Like researchers/scientists driving to work.
The switch to EV is happening: but things like packing as many people as possible in cities and preventing them from having a car and giving them authorization to go to the country-side once a year ain't happening any time soon.
We should be celebrating the switch to EVs and to safer cars instead of hating on individual transportation.
1) Plug-in solar and batteries are plug-n-play. This is the first step to teach everyone energy literacy and numeracy.
2) Vertical panels immediately add 3 - 4 hours. Vertical panels have zero real estate cost and no need to build costly and slow transmission infrastructure. Every building in a city can produce energy.
3) EVs to store excess energy during the day and supply power back to the grid later.
1.8 billion vehicles connect 4 billion buildings. Buildings can produce clean energy and EVs can store energy. The lowest hanging fruit is to make sure all new buildings are built to produce, and all new vehicles are EVs. New buildings can be built with vertical panels and rooftop. The easiest thing to do is change building code, thats it. Then, we can deal with the built environment.
A nuclear deployment takes 3 - 5 decades, costs continue to skyrocket, actually needs nuclear scientists to design and run.
Which one do you think is a better choice? If you were an investor, would you put your money on a nuclear plant and wait 3 - 5 decades for returns?
I bought a couple reasonably priced HEPA purifiers and I change the filters on schedule. Replacement HEPA filters are very cheap.
Also watch out for things that we do indoors that can generate bad air quality. I had a friend who bought a VOC meter and noticed very high readings in his kid's room. He traced the source to his chemical and paint cabinet nearby, which he never considered because he couldn't smell anything. Throwing out a lot of the old containers dropped the measurements to the unmeasurable range.
The more effective the filter the more it restricts airflow. If a filter is only 99% effective instead of 99.99% but allows double the airflow, it provides nearly double the CADR. To benefit from HEPA you need a clean side and dirty side, like in a clean-room setup.
What matters is the gradual removal of particles from the air.
The HEPA purifiers I have move enough air that everything gets scrubbed. It works.
My house has a separate central air system with a non-HEPA air filter with a decent MERV rating for the bulk filtering. The HEPA air purifiers do the scrubbing of finer particles.
Don’t overthink this. This looks like knowing just enough to be dangerous but missing the big picture.
You have an air purifier in your kid's room. If this is a fairly large apartment or a house, and you have central air running, how much purer is the air in that room? If your central air system is modern and continuously circulates air throughout the house at a low fan speed, you're effectively trying to purify your whole house with that low-output room-sized HEPA filter. Have you done measurements to see if it does anything?
I used to work in the cleanest room in the state, that wasn’t a lab, back when I lived in Adelaide, and top-inlet button-outlet in a raised floor data centre is how the air handling units in the main data hall worked, so you can simulate that to a certain extent.
> The more effective the filter the more it restricts airflow.
This isn’t the whole story. Surface area and flow rate are factors.
A residential home is aiming to improve air quality, rather than grow flawless silicon ingots etc.
If you get to recycle the air through the filter several times, MERV-13 offers much better performance tradeoffs for a residential air purifier because you can recycle the air through it much faster at acceptable noise levels. My home air purifier recycles the volume of my home every 15 minutes or so, vs HEPA filters which produce totally clean air, but since it just mixes with the dirty air that doesn’t matter as much as the rate at which it cleans air.
But a HEPA filter is better than no filter. Even if would be more effective with another.
(Also depends on size of hepa filter and room to clean. Large enough filter and small enough space and Hepa can clean all the air)
If you put a standard sized air purifier with a HEPA filter in it into a room it will absolutely lower the dirty air of the room. Because over time you're lowering the particle count.
If I turn my air purifier on in my room even with the door open the air quality sensors improve their readings quite dramatically.
In locations with central air handlers, the filter in that handler already serves this purpose. That’s how my house is set up: Central handler has a high throughout MERV filter. Several rooms have additional HEPA purifiers.
The parent comment also has a fallacious argument in assuming that the CADR is too low if a HEPA filter is present, but even the cheap HEPA purifiers I bought have sufficient CADR to cycle the room over and over.
If you’re in a location with no central air handler (only mini splits or no air conditioning at all) and you have a giant space to cover and you have a constant exchange of air from the outside to overwhelm your filtration (must leave windows open, for example) then what the commenter above would apply. You would be better with a higher throughput, lower rated filter.
For everyone else, it’s kind of a misplaced “well actually” take that has just enough information to feel truthy but misses the bigger facts.
Air purifiers are designed to run 24/7 and all they do is catch particles. Eventually all the particles will be caught. The one I got also detects if there is a lot of particles and will spin faster accordingly.
Air filters don't work like sieves. The smallest particles are easier to block than the mid-sized particles. See:
https://en.wikipedia.org/wiki/Mechanical_filter_(respirator)
Clean Air Delivery Rate is often specified for specific pollutants. One is smoke, which is mostly small particles.
If you pair if with an Apollo AIR-1 you can have home assistant ramp up and down the fans with a PC fan controller based on live readings of PM2.5 in your home. I did this with the help of Claude code.
https://www.thingiverse.com/thing:6826527
https://makerworld.com/en/models/2470181-nukit-tempest-euro-...
However they look somewhat commercial and I'm not sure the funding/incentives so definitely corroborate with other sources.
Having said that, there are reviews of some DIY models reviewing CADR[1], and it's bizarre to complain about testing decibles since Arctic P14 fans, the most commonly recommended fans, are a thouroughly tested product. Running them at around 25% based on lower PM2.5 readings is almost inaudible from experience.
> Those 2-in-1 filters do exist but cost more. And many are scams because they don't have enough volume of activated carbon.
Any filter with a little bit of carbon added is going to be useless after a few days, or maybe even hours.
The only VOC filters that work have multiple pounds of carbon, with the good filters having upwards of 10-20 pounds. It also has to be replaced regularly.
You can safely put a washer and dryer on the upper floor of a house if you add a proper floor drain, but you’re unlikely to see anyone add a floor drain in new construction because buyers aren’t looking for it. Now multiply that by everything a buyer isn’t looking for and you’re talking real money.
The real activated carbon filters have 10s of pounds of carbon. The little black foam thing that comes with those 2-in-1 carbon filters is useless.
I drive the car, you buy the purifier.
You don’t think the parent commenter is also using transportation?
The pollution from transport also occurs with trains, buses, and any other vehicle that has wheels, brakes, or moves fast enough to stir up the air and kick particulates into the air.
People do what they can and control what’s within their reach.
And yes other means of transport also does pollute, but amount is is critical here. You need much less public transport than you need individual cars.
I perfectly understand that there is no quick solution (only quick patch with air purifier) so thats why we should not normalise this and remember to complain (after buying air purifier)
buying a new house will have $40k in reltor fees alone, $2k for movers, plus the, you know, hundreds of thousands for the new house. and what if I like my current house, it's in a busy hip area?
or should I launch a multi-year lobbying campaign in the city and/or state and/or national level to have roads moved?
DHH is also a fan (pun not intended?): https://world.hey.com/dhh/air-purifiers-are-a-simple-answer-...
https://en.wikipedia.org/wiki/Sanatorium
I guess the modern descendants are the health retreat, the rural airbnb, and the day spa that offers oxygen therapy.
Funny part is that locals here are absolutely scared of any sign of draft or direct aircon. All while it's what actually saves their health lol.
I have always been and am still baffled by this. My whole family loses their minds if there is even a slight draft or AC, whether in the house or car. When my brother visits he incessantly closes car vents and windows. Parents constantly nag to put on warm clothes and avoid drafts etc., and when we inevitably get sick a few times a year mostly from school transmitted cold viruses they gloat about it.
Maybe it's a cultural thing from times without good heat/insulation where drafts meant an actual freezing house, which, yes that would actually have an impact on health.
I’ve got a sensor that can detect no2 and it noticeably spikes when using gas. Switched to induction after that.
Do you have a source for that? Because as far as I can see, asthma isn't _that_ less common in countries where gas stoves are barely used, such as germany. Still has like 60-70% of the asthma cases the US has. There's also a ton of other pollutants the US hasn't yet forbidden, but the EU has, which could also explain a lot of the difference in rates.
Don't get me wrong, it's certainly a good idea to get rid of gas stoves. I just think it's a bit much to declare them the primary cause of asthma.
'Replacing gas stove can help asthmatics as much as some drugs, US experts find'
https://www.theguardian.com/environment/2026/jul/24/replacin...
That makes sense but the unverified claim is that gas stoves are the main contributors to asthma.
It's better now with more EVs and low pollution vehicles and the street should be pedestrianised from October.
Does the area immediately above where the gas stove was have an exhaust fan that vents to atmosphere?
I would have assumed a properly specced exhaust fan would capture and remove combustion products from a gas stove?
I suspect a sufficient ventilation would require something more like a lab fume hood that can pull a negative pressure on the area around the stove.
And from what I have seen, a good number of exhaust fans are straight up fake and just ventilate back in to the room rather than ducted outside.
Surprise surprise.
There is evidence of a lot of ugly diseases caused by this, without even mentioning the constant 40+ dB background noise.
Plus the idea of having everything within a 15 minute walk including access to public transport.
And pollution from bus or tram is much easier to control. Looking at you petrolheads who like to "Rolling coal"
In London now many if not most buses are electric.
Once you build anything of significance, a highway gets built to it anyway.
Living in the country gave me bad hay fever/asthma in the city much less asthma.
Not exactly the same thing.
the only plants that survive these days are the ones that spam a ton of pollen, so it gets selected for aggressively.
1. London when the ULEZ was brought in was already a lot less polluted than historically.Are there gains from that? London was not that bad by global standards.
2. This was followed by the benefits of COVID lockdowns (not a phrase often used!) as pollution dropped much further.
3. Is this effect even across London? Suburbs vs centre, different types of housing etc.? I grew up a the edge of London and the difference in pollution was visible (i.e. you did not need instruments to see signs of it).
4. There was also a reduction in sales of diesel cars which had been heavily encouraged (because of lower CO₂ emissions) in previous decades.
5. As the articles notes, there have been a lot of other changes at roughly the same time. It only mentions one, but there have been significant lifestyle changes, so a lot of potential confounding variables.
2. Definitely kickstarted it, but we're looking at taking that impact and continuing it for some 5 years after covid ended now.
3. You can look at the ULEZ map and it really covers everything but the outer tube line suburbs [1].
5. The control group in Luton, presumably, has the same lifestyle changes - it's not that far away (about 30 miles), so it is as close as you can get to a one to one comparison, not accounting for the fact that Luton is likely to be more deprived than London (especially in the council estates, which have horrible reputations).
[1] - https://tfl.gov.uk/ruc-cdn/static/cms/images/ulezdetailedmap...
2. does the study separate impact during lockdown from after?
3. my question is whether it had the same impact everywhere. I would guess very much not.
5. the impact of those changes might not be the same from a much better baseline, nor are lifestyle changes the same in a big city and a small town.
It's incredible this is even in debate. It's one of those intuitive things well known since the reduction of coal burning and smog during the industrial revolution in London?
They made it into a culture war topic.
We're going to see the same when EV-only mandates, true zero emissions zones, start appearing across the next decade.
https://www.theguardian.com/politics/2023/aug/01/fake-tweets...
Show you how people are out of touch with reality. Even something commonsensical like what you mentioned is often countered with - "Show me the data"
'"I was absolutely stunned when I first saw the results," Prof Chris Griffiths, a senior author on the study, at Queen Mary University of London, told the BBC."'
HN needs a 's/^scientists stunned by/Scientists notice/i' filter for Titles.
Except that they do undo the damage.
“ After 15 years, your chances of getting lung cancer are almost the same as someone who has never smoked.”
https://www.verywellhealth.com/risk-of-lung-cancer-in-former...
This study looks more broadly, notably also at onset of smoking:
https://jamanetwork.com/journals/jamaoncology/fullarticle/27...
And this is the TL;DR:
“ Thus, those who quit smoking at ages 15 to 34, 35 to 44, 45 to 54, and 55 to 64 years avoided an estimated 100%, 89%, 78%, and 56% of the excess cancer mortality risk associated with continued smoking, respectively”
Also, quitting smoking definitely eases a number of symptoms, especially if you're not at the point of chronic emphysema. The reduction of inflammation triggers alone after a bit of time is fairly significant. Less coughing, less mucus buildup, etc.
'"I was absolutely stunned when I first saw the results," Prof Chris Griffiths, a senior author on the study, at Queen Mary University of London, told the BBC.'
https://old.reddit.com/r/OldSchoolCool/comments/1v73w9s/hydr...
Visiting London used to mean blowing your nose to black snot for a week afterwards, these days living in London it's pretty good.
Sources:
https://www.bbc.com/news/articles/c75q9d2pqyeo https://www.theguardian.com/environment/2026/jun/12/emergenc...
Whenever my best mate goes on about having access to "cultural experiences" that I don't have for living in the sticks I remind him it comes at the cost of massive tube bogeys. :P
Rising natural gas prices due to the Ukraine war also made even more people install fireplaces (as if that was cheaper).
https://clara.southlondonscientific.com/
He also runs this repo:
The study is supposed to measure how clearing up pollution in London improved children's lung function. The decrease in London was meaningful — NO2 fell about 22%. But particulates fell faster in Luton and NO2 in London is still roughly double Luton's. The gap is larger than the decrease.
By 2022 both cohorts get the same results on blow tests. But how does this happen if we believe that the study's dose-response model is true?
Put another way, if the change in London NO2 is so crucial, how come it doesn't matter that the absolute value is still double Luton's?
>At baseline, 184 (14%) of 1280 children with successful FEV1 measurement in London had a clinically low FEV1 (pre-bronchodilator FEV1 <80% of predicted value) compared with 126 (9%) of 1339 children in Luton (appendix p 8). At the end of the study, these values had dropped to 51 (9%) of 585 children in London and 41 (7%) of 606 children in Luton (appendix p 8).
So the proportion of children with low lung function dropped from 14% to 9% in London, and from 9% to 7% at the comparator site in Luton. It's not that much different, though any improvement is obviously welcome.
https://www.thelancet.com/journals/lanpub/article/PIIS2468-2...
even New York is so much more better than Bangalore or my small village in the middle of coffee farms
I will never forget watching this documentary about a Canadian man, Doug Rogers, who went to Japan in 1964 to train martial arts at a dojo. This YouTube video[1], watch it from 1:00 to 1:10. The air pollution is simply stunning. It shows you just how terrible the air pollution was in Tokyo in 1964. Today, it is night and day. The same is true for most large cities in highly industrialised nations.
I assume you mean that the increased air-exchange (purified or not) helps CO2 that originates inside the house to leave promptly? (Equalizing it with the outdoors.)
Literally "keeping CO2 out" is a much trickier and more-expensive proposition.
Note that because this purifier is mounted at the window, it filters incoming air from outside, not the indoor VOCs that are already in the residence. The indoor VOCs will simply have to get exhausted from elsewhere due to the air pressure.
What I am suggesting is that my need for activated carbon is slightly less because I am rapidly pushing the VOCs out in the resulting exhaust.
Sure but they had to live in Luton
So unlike greenhouse gases, which can last in the atmosphere for years, seems like NO2 and particulates only stay in the air for less than a day or a few days. This is an amazing little fact because we can start small and call for meaningful reform where we live without requiring a global coordination. Maybe there will be a global consensus later but it doesn't matter because we can start making improvements today within our own local context. The bonus is we will likely also lower our own carbon footprint as we reduce our other emissions. I think this is the "selfish" breakthrough we need to convince people.
When I say it doesn't matter, I don't mean like cross border contamination does not happen but rather that we can improve our own lives with our own action regardless of what others do.
The obvious actionable thing that you can do for your own life is to stop using or being around gasoline or petrol powered two stroke engines such as in a leaf blower. But we can do more. We can completely ban these two stroke engines from being sold at all and that will bring meaningful improvements in weeks, not years.
The problem is to make more impact, we will need to actually get people to give up or retrofit their existing equipment. We will need to educate people about the harms that these things cause and why the change is good. However, in today's siloed world, I don't think it will be easy at all. So perhaps the most difficult part ironically in a very connected and yet siloed world is the marketing of this idea and connecting the required change in behavior with the benefits.
As we saw with the leaf blower example, the costs are concentrated, yes but so are the benefits! The benefits are NOT at all diffuse because guess who benefits the most from not inhaling in gasoline fumes? The person operating the leaf blower!
https://www.telegraph.co.uk/news/2026/05/04/scourge-of-londo...
We had a lot of construction work in the neighborhood, our house covered in fine dust particles each day. My kid got asthma in the same period, keeps asking when she can stop taking the medicines, and I say "I don't know" thinking "probably never". But maybe now the construction work is over, there is hope? (And if construction starts again, we know that it is better to move, because there is hope.)
In the UK's far-right media culture, Khan's ULEZ is painted as fringe extremism, not as a common sense public health measure.
There is a big difference between believing something is true, and demonstrating it is true and measuring the effect. One is a vibe. The other can drive policy.
History holds enough examples of intellectuals who out of absolute lack of any human compassion subjected fellow human beings to anti-humane conditions, hoping to find and push the limits of their bodies and psyches in order to maximize profits, ahem, sorry, optimize spending.
And those who you hope to be able to set "policies" on further cramming of people into the machine are either exactly those who profit off that, or eat crumbs from that table.
Yet there are always heart/right hemisphere dead morons who need precise numbers and conclusions written in blood instead of simply relying on common sense.
It's annoying though that EV's need that extra Darth Vader on wheels sound to warn pedestrians, I'd prefer them to be as quiet as possible.
But I'll take it if diesels and two-strokes will die in a fire
We don't all live in the city.
Europe has quite a few cities where traffic is increasingly discouraged from going to the inner cities. Cities like Paris and London are much transformed from what they used to be and it shows in the health statistics.
It's not just the particulates but also nitrous oxides (nox) produced by combustion engines. Nox is correlated with lots of health issues. Take it away and you see lower rates of chronic lung issues, cancer, development issues with kids, etc.
But yes, tires are also an issue. But a fairly minor one to anything coming out of a combustion engine.
Mass transit indeed is nice in big cities. Removes the need for taking the car.
No shit Sherlock.
Regen braking means significantly less brake dust, especially at city speeds and with blended braking.
> Although…rail might solve those?
Trains still have brakes. Some can regen brake but because they usually don’t have batteries they need the rail or overhead gantry to support inputs.
But on a passenger-mile basis, I expect an electric train produces essentially no particulates compared to a car, even a light rail on tyres. I do not however have numbers.
It's much less wear and tear than friction brakes.
https://engineering.nyu.edu/news/subway-air-pollution-dispro...
But I expect it's much better in open-air rail systems.
In some areas of London the ULEZ has been so successful that the measured NOx is now coming mostly from gas boilers used for heating, probably mostly old large commerical units.
So shifting from gas boilers to heat pumps and from gas ovens and stoves to electric/indusction is also beneficial.
So yeah.
That said not clear to me about PM2.5 is I've never seen anything legit seeming that tries to characterize the harm based on the type/source. Though it seems agreed diesel is especially bad.
However most people live next to a busy street ...
(Actually, the _very_ busiest streets are probably major bus gates (where, again, there are no cars), those can have fairly ridiculous density at peak times.
I bet if some youtube weirdos pushed out videos against "big soap" for making us unnecessarily clean our hands after pooping... we'd have a growing following of angry "freedom from big soap" people.
At one point during Covid, I tried (not very hard at all) to float a conspiracy that the vaccine was in fact not the poison, but the antidote. That Covid was deliberately designed by governments to filter the 'independent thinkers' (who won't take the vaccine) from the sheep (those who do take the vaccine). So by not taking the vaccine, you were giving the governments what they wanted.
This was because the conspiracy that governments were killing the loyal sheep with the vaccine, therefore only leaving the 'independent thinkers' behind, made absolutely no sense at all to me.
https://www.theguardian.com/world/2026/jul/29/respiratory-cl...
https://energyandcleanair.org/publication/health-impacts-of-...
https://www.theguardian.com/commentisfree/2026/aug/18/ulez-h...
So EVs are better than ICE for air quality, but fewer cars even better.
Particles caused by tyre and brake wear are going to be much larger than, say, diesel particulates.
That size differences is going to affect how easily they can be absorbed into your lungs.
A new Routemaster double decker weighs 12.6 tonne and carries up to 80 passengers. A typical car weighs 1.6 tonne and carries up to 4 passengers, they both have two axles. If we guess at half the rated passenger count then we have:
Bus damages the road (12.6/1.6)^4 = 3845 times as much as a single car.
I'm sure my calculation is imprecise but surely not that far out. What have I missed or misunderstood?
Which also means roads for heavy transport is 20k times more expensive!
I recommend getting one of these https://www.youtube.com/watch?v=sQGfO4hNb60 and just slapping a MERV 12 to 16 filter on it, you can get a whole roll off aliexpress for cheap and replace them monthly if you wanted to and it would be cheaper than 1 hepa filter replacement. They can also filter vastly more air, while you can keep hepa for 6 to 12 months MERV will filter a lot more air.
In this case:
"While we would expect children's lungs to grow year on year, our results indicate that the London children's lung growth had accelerated during the four years to 'catch up' with the control group in Luton to reach similar levels of lung capacity," researchers say.
"I was absolutely stunned when I first saw the results," Prof Chris Griffiths, a senior author on the study, at Queen Mary University of London, told the BBC.
"The speed of catch up in lung capacity in the London group was surprising and impressive."
[0]: https://www.zh.ch/content/dam/zhweb/bilder-dokumente/themen/...
"High diesel-family averages were approximately 1–3 g NOx/km. Most gasoline-family averages clustered around approximately 0.02–0.15 g/km."
[1]: https://publications.tno.nl/publication/34635198/KxBBl3/TNO-...
"TNO tested in-use vehicles directly at the tailpipe. Three diesels with DPFs emitted: 3.9–5.3 million particles/cm³ at warm low idle. The same report measured warm Euro 5 direct-injection gasoline cars without gasoline particulate filters at: 50,000–60,000 particles/cm³ at low idle."
[2]: https://d-nb.info/137495313X/34
"In 2017, the highest diesel was approximately 12 g black carbon/kg fuel, versus roughly 0.4 g/kg for the highest gasoline car. In 2023, the highest diesel was roughly 8 g/kg, versus approximately 0.7 g/kg gasoline."
[3]: https://trueinitiative.org/insights/true-brussels-emissions-...
"approximately 5% of measured Euro 5b/Euro 6 diesel vehicles exceeded one million particles/cm³, and this small group produced more than 90% of the particle emissions from the tested diesel group"
"Levels in the raw 2S scooter exhaust were as high as 300,000 μg m−3 or 146 p.p.m.(v) from idling. The EU annual mean limit for the protection of human health is 5 μg m−3 (ref. 13), while the US National Institute for Occupational Safety and Health recommends that workers wear special breathing equipment when exposed to benzene at levels exceeding 1 p.p.m. for 15 min. Waiting in traffic behind a 2S scooter, for example, at junctions and while the scooter is idling, may therefore be highly deleterious to health." [0]: http://dx.doi.org/10.1038/ncomms4749
But cities are full of shitty mopeds and old Vespas, for no benefit but cultural cosplay reasons.
It's ridiculous that we voluntarily emit fossil fuel and oil fumes in our densest urban areas.
There is a big difference between believing something is true, and demonstrating it is true and measuring the effect. One is a vibe. The other can drive policy.
Hormesis and natural selection have been driving factor of evolution for a long time.
Larry Niven played with this in one of his stories; a time traveller from the far (and highly polluted) future has to use mechanical breathing assistance, because the levels of CO2 in the air in the past weren't high enough to prompt the breathing response properly (human breathing is controlled largely by blood CO2 levels).
Anyway, by your own line of thinking, wouldn't sensitive lungs be an advantage? The incentive to find cleaner air is also breaking away from the pack. Since humans are social creatures, that's more likely to look like new leadership for followers who have their own reasons to break away.
Every civilization in history has started out that way. It takes more than mere brute force to beat the competition. Survival is just as much about picking your battles and working smarter.