3 ms·

It's always interesting/concerning when I blow my nose after a day in London: there is a lot of black residue in the snot. apologies for the disgusting picture

butteroverflow 7y ago
Same thing here, except I live a few thousand kilometers away from London. When I am too lazy to wash the windows for a month or two, the next rag goes straight to the trash bin -- it's so black and soaked with soot you can't really clean it afterwards. It would be nice to see the inside of the lungs of someone who spent a life here.
tomatocracy 7y ago
A lot of the air quality problem isn't cars though - it's also things like construction equipment and just sheer number of people passing through, especially in enclosed spaces. The London underground has some of the worst pollution in the capital, particularly in terms of particulates and bacteria. Anecdotally you might notice eg after holding the handrails on some of the escalators that your hand comes back black. There's a famous statistic quoted that a 20 minute journey on the Northern Line is as bad for you as smoking a cigarette. There's an interesting article on this effect here: https://www.railway-technology.com/features/featureis-the-air-on-london-underground-fit-to-breathe-5918758/ https://www.railway-technology.com/features/featureis-the-ai...
alex_duf 7y ago
This especially true if you take the tube, and heavily varies depending on the line. Victoria line and Nothern lines are especially bad. If you stand at one hand of the platform, you can see some weird "mist" when looking at the opposite side. That's just a high concentration of PM2.5 and PM10, and that's what causes the black snot. It's been shown the pollution level in the tube is 30 times worst than the worst street in london. [1] I moved out of the centre of london and commute by train partly for that reason. Life's short, let's not make it shorter. [1]: https://www.theguardian.com/uk-news/2019/jan/09/london-underground-air-pollution-report-concerns-northern-line-particulates https://www.theguardian.com/uk-news/2019/jan/09/london-under...
- Theodores 7y ago
  The problem is cleaning. It doesn't happen. Compare how your former communist country tube stations look compared to what there is in London. The whole lot has to be spotlessly clean for it to work, in London they clean the seats on the trains and do the maintenance work there, but the actual tunnels get cleaned once in a blue moon. The whole thing needs to be polished and polish-able. London Underground isn't built like that. A fair amount of the dirt is from the streets above, so tyres that wear to also wear the road surfaces, that sort of cruft gets drawn all the way down into the Underground. As for actual pollution levels then this depends on where you are on the network. TfL don't measure enough to give a heatmap of pollution, updated hourly. Your statistic from the Guardian sounds about right, generally speaking though the particulates are at 10x the EU max levels. In a communist style country you could have an army of people polishing the tube stations and the tunnels as part of some National Service. But, in a Western Democracy where everyone has to pay a four figure sum for rent + travel no matter how they try and mix it, this isn't going to happen. They have tried to create magic sweeper trains to hoover everything up but it hasn't been a success. Really that is what is needed as well as the trains being built to 'hoover as they go', using the air-con to filter out all the cruft.
  - _visgean 7y ago
    No, the problem is ventilation. https://en.wikipedia.org/wiki/London_Underground_cooling https://en.wikipedia.org/wiki/London_Underground_cooling In eastern europe we have very effective ventilation - for number of reasons, one of them is that it was built much later, the other is that some of the station were built to serve as a nuclear shelter so they had to have very safe ventilation systems...
- ubercow13 7y ago
  Yep, there are many parts of the tube where I literally have to hold my breath because the air is so bad.
Angostura 7y ago
If you travel by tube, a lot of that is sloughed off dead skin.
- ubercow13 7y ago
  Most of the tube dust is oxidised iron particles from the trains

butteroverflow 7y ago

Same thing here, except I live a few thousand kilometers away from London. When I am too lazy to wash the windows for a month or two, the next rag goes straight to the trash bin -- it's so black and soaked with soot you can't really clean it afterwards. It would be nice to see the inside of the lungs of someone who spent a life here.

tomatocracy 7y ago

A lot of the air quality problem isn't cars though - it's also things like construction equipment and just sheer number of people passing through, especially in enclosed spaces. The London underground has some of the worst pollution in the capital, particularly in terms of particulates and bacteria. Anecdotally you might notice eg after holding the handrails on some of the escalators that your hand comes back black. There's a famous statistic quoted that a 20 minute journey on the Northern Line is as bad for you as smoking a cigarette. There's an interesting article on this effect here: https://www.railway-technology.com/features/featureis-the-air-on-london-underground-fit-to-breathe-5918758/ https://www.railway-technology.com/features/featureis-the-ai...

alex_duf 7y ago

This especially true if you take the tube, and heavily varies depending on the line. Victoria line and Nothern lines are especially bad. If you stand at one hand of the platform, you can see some weird "mist" when looking at the opposite side. That's just a high concentration of PM2.5 and PM10, and that's what causes the black snot. It's been shown the pollution level in the tube is 30 times worst than the worst street in london. [1] I moved out of the centre of london and commute by train partly for that reason. Life's short, let's not make it shorter. [1]: https://www.theguardian.com/uk-news/2019/jan/09/london-underground-air-pollution-report-concerns-northern-line-particulates https://www.theguardian.com/uk-news/2019/jan/09/london-under...

Theodores 7y ago
The problem is cleaning. It doesn't happen. Compare how your former communist country tube stations look compared to what there is in London. The whole lot has to be spotlessly clean for it to work, in London they clean the seats on the trains and do the maintenance work there, but the actual tunnels get cleaned once in a blue moon. The whole thing needs to be polished and polish-able. London Underground isn't built like that. A fair amount of the dirt is from the streets above, so tyres that wear to also wear the road surfaces, that sort of cruft gets drawn all the way down into the Underground. As for actual pollution levels then this depends on where you are on the network. TfL don't measure enough to give a heatmap of pollution, updated hourly. Your statistic from the Guardian sounds about right, generally speaking though the particulates are at 10x the EU max levels. In a communist style country you could have an army of people polishing the tube stations and the tunnels as part of some National Service. But, in a Western Democracy where everyone has to pay a four figure sum for rent + travel no matter how they try and mix it, this isn't going to happen. They have tried to create magic sweeper trains to hoover everything up but it hasn't been a success. Really that is what is needed as well as the trains being built to 'hoover as they go', using the air-con to filter out all the cruft.
- _visgean 7y ago
  No, the problem is ventilation. https://en.wikipedia.org/wiki/London_Underground_cooling https://en.wikipedia.org/wiki/London_Underground_cooling In eastern europe we have very effective ventilation - for number of reasons, one of them is that it was built much later, the other is that some of the station were built to serve as a nuclear shelter so they had to have very safe ventilation systems...
ubercow13 7y ago
Yep, there are many parts of the tube where I literally have to hold my breath because the air is so bad.

Angostura 7y ago

If you travel by tube, a lot of that is sloughed off dead skin.

ubercow13 7y ago
Most of the tube dust is oxidised iron particles from the trains