A little knowledge is a dangerous thing.

[baratron]

Never trust journalists with science. A report in the Evening Standard this week suggests that travelling on the Tube is as bad for you as smoking two cigarettes. Apparently, "scientists went to Warren Street, a deep-level station where readings were 996 micrograms, 70 times the level of dust found in an average office. At Tottenham Court Road there was a similarly high level."

Now, I know about air pollution. For a start, "micrograms" is not a sensible unit for air quality. If you don't specify the unit of air used, the figure makes no sense - was that 996 micrograms in a small volume of air, or in the entire station? Also, you have to state over what period of time the readings were taken. Usually, particulates are measured in micrograms per metre cubed, and the readings taken averaged over 24 hours to provide an instantaneous snapshot.

If the quote of "70 times the amount of dust found in an average office" is correct, then the unit of the 996 is indeed micrograms per metre cubed. And this makes no sense. At a level of 100 micrograms per metre cubed or more, someone like me with endemic asthma would be in considerable discomfort. It's as heavy as the pollution level immediately adjacent to a large motorway.

I can't believe those figures are right. Even 99.6 micrograms per metre cubed would seem too much. 100 micrograms per metre cubed of particulates is enough that you can smell and taste it in the air. Remember the heavy smoke smell that hangs in the air for a couple of days around Bonfire Night? That's what a level of 100 micrograms per metre cubed feels like. And 996 micrograms per metre cubed! That's more polluted than the most serious pollution episode that I studied in my PhD. If the Tube was really that bad, asthmatics would be dying every time they tried to use it.

I want to see the actual report for myself, so I can find out what the figures really were. My belief is that the scientists found a level of 996 micrograms per metre cubed in 24 hours. Not an average level - a total level. This would make sense, as it would average down to 41.5 micrograms per metre cubed in one hour. I could believe this to be the level of dust pollution on the Tube. It's high enough to cause health problems if you were to be exposed to it continually, but not so high that someone with medium-grade asthma would notice it on a single journey. It would be important enough to issue a report on it, as it is sailing close to the WHO safe limit, but it would only be actively dangerous for Underground workers who spent 12 hours a day out in the tunnels without the protection of a face mask. Not noticeably more dangerous for commuters than simply standing in a London street.

Comments

[lovingboth]

Yeah, when I first started coming to London, if you used the tube and blew your nose, the contents of your handkerchief were black.

The smoking ban after the Kings Cross fire helped hugely...

[narenek.livejournal.com]

Wasn't smoking banned on the tube for ages before Kings Cross?

People just tended to start lighting their fags on the up escalator as they headed for the exit?

Smoking on the trains/platforms was banned
before then though (possibly after a series of fires on trains in the 60s though I'm not certain of that).

[lovingboth]

Smoking underground on trains was certainly still allowed in 1979, which was the first time I was in London for more than a day.

I remember having to go in a smokers' carriage :(((

[lovingboth]

Ah, you're right. 9th July 1984 saw the start of a one year experimental ban which became permanent. The King's Cross fire was in 1989. Gosh.

[londonstatto.livejournal.com]

It wasn't until after KX that they really clamped down on it. There was a documentary on TV over the summer - they mentioned that people would often light up on the escalators. Hopefully, the LUL staff would give such morons the bollocking they deserve these days.

Hmm!

[bethdeth.livejournal.com]

That was well-spotted and very interesting, h-l. We definitely need to take a more objective look at so-called "scientific facts" printed in mass media outlets. You've got the name of the person who conducted the study (Dr. Croxford), so he should be easy to look up in the relevant journals. Even though it was for the Beeb, it seems likely that it would be published in some academic outlet *somewhere*, especially if it's "out today."