Times article re: urban cycling and heart disease

[Martin Dann]

In message <[email protected]>
Peewiglet <[email protected]> wrote:

> Newby said: “While they are exercising, cyclists breathe two to three
> times as much air as car drivers.

I have seen one or two [1] studies on telly a few years back, that both did
a comparison of people who drove and cycled the same polluted route.

After the end of the journey it was shown that the car drivers had more
pollutents in their blood than the cyclists.
This was attributed to two factors:
1) There is a higher lever of pollutents inside the car than outside.
2) because "cyclists breathe two to three times as much air as car drivers"
and have a higher metabolic rate we breath the pollutents out faster than
car drivers.

Martin.

[1] I can't remember if I saw two different, or the same one twice.


--
According to the human genome project, humans are 50-60% bananas.
When emailing me, please include the word Banana in the subject line.

 

[Nick Kew]

Chris Malcolm wrote:

> I suspect this is an "obvious" assumption made by someone who hasn't
> studied the research. Tests made on the blood of urban rush hour
> cyclists travelling at various speeds showed the paradoxical effect
> that the faster heavier breathing cyclists ended up with less
> pollution in their blood. Wish I could recall the source of that
> interesting research. I suspect it's at least twenty years old. I do
> recall that nobody was able to explain this paradoxical finding. There
> was speculation about heavy breathing somehow increasing some kind of
> natural flushing out effect.

Yeah, I've seen that. I think one source may be Richard Ballantine,
who isn't necessarily authoritative, though. And it's the higher
circulation that improves the body's natural defences when exercising,
which seems entirely likely and reasonable

> The most important finding, however, was that they compared the blood
> pollution levels of the cyclists with the blood pollution levels of
> car drivers. The levels in car drivers' blood were very much worse, in
> significantly greater proportion than the higher level of pollutants
> inside the car than at cyclist head height. That gave some more fuel
> to the idea of some as yet unknown "flushing" effect of exercising
> while breathing polluted air.

But this wasn't comparing cycling with anything else. I suspect the
original study may be entirely unremarkable (publish-or-perish academics
in search of a subject to write about), and just got picked up by some
weasel journo with a chip on the shoulder about some smug and healthy
cycling coworker ... or some such scenario.

>>Next month the Committee on the Medical Effects of Air Pollutants, a
>>government advisory body, will publish a report highlighting the risks
>>of heart disease from traffic pollution.

Now if that could get the kind of attention pointed at smokers ...

--
Nick Kew

 

[Ambrose Nankivell]

Chris Smith wrote:
> Peewiglet wrote:
>> Did anyone see the article in yesterday's Times? I coudn't see how to
>> make a link, so here it is.
>> -----
>>
>> Urban cyclists raise their risk of heart disease
>> Sarah-Kate Templeton, Medical Correspondent
>>
>>
>> CYCLISTS may be doing themselves more harm than good by pedalling to
>> the office along congested roads, according to pioneering research by
>> the British Heart Foundation.
>>
>
> Hmm... is the air inside the traffic producing the fumes any better I
> wonder?

No.

(copied from a previous post of mine (Message-ID
<[email protected]>))

(quoted in "cycling: the way ahead for towns and cities" by the European
Commision)


all concentrations in micrograms per cubic metre air breathed
Cyclists Motorists
CO: 2670 6730
NO2: 156 277
Benzene: 23 138
Toluene: 72 373
Xylene: 46 193


Cyclists breath two to three times as much are as motorists, though, so some
exposures may actually be higher, but not those aromatic hydrocarbon ones.


The exposure of cyclists, car drivers and pedestrians to traffic-related air
pollutants. Van Wijnen, Verhoeff, Henk & Van Bruggen, 1995 Int. Arch. Occup.
Environ. Health 67 187-193


HTH

--
Ambrose

 

[Tony Raven]

Chris Malcolm wrote:

>
> Does anyone have citations for this old research I'm remembering?
> Sounds as though it has suddenly became rather relevant!
>

Is this any use:
http://www.dft.gov.uk/stellent/grou...ts/page/dft_science_504480-08.hcsp#P416_44997
http://www.ncbi.nlm.nih.gov/entrez/...d&dopt=Abstract&list_uids=11712590&query_hl=2

The statement was made in a 1999 National Cycling Strategy publication
but the references do not track through to anything substantial. One
interesting thing I found was the worst place for particulate inhalation
in London was on the tube!
http://www.ncbi.nlm.nih.gov/entrez/...d&dopt=Abstract&list_uids=11712603&query_hl=2


--
Tony

"I did make a mistake once - I thought I'd made a mistake but I hadn't"
Anon

 

[Tony W]

"Al C-F" <[email protected]> wrote in
message news:[email protected]...

> > What's the betting the proposed solution is to make the victims change
> > their behaviour, not the actual causes.... move the cyclists away, not
> > decrease the traffic...
> >
> That would be as stated:
> "We need to locate cycle lanes away from major roads."
>
> I wonder if this 'damage' offsets the health benefits of cycling.


So what about pedestrians and car drivers? Surely they are also exposed.
Perhaps we should move cars away from people -- they do seem quite
dangerous!!

T

 

[Mark Thompson]

> I'm suggesting most cyclists aren't that stupid to start
> with

We're talking about POBs (people on bikes) rather than cyclists. Half of
the numpties really are that stupid, but they're on the paths instead.

Skimreading through the article, I expect he needs to find out what sort of
air we're breathing in[1], and what sort of air drivers are breathing in,
then redo the experiment.

Having said all that, the article is just scaremongering - if the damage
were really that bad, the experiment would never have got past the ethics
committee

[1]A cyclist is breathing in air from a much higher point than a car
driver, and I'd be guessing that the pollution gets worse the closer you
are to the ground. Maybe a pollution detector thingy mounted on someones
shoulder and another in someones car, and then seperate experiments with
more realistic pollution levels (and possibly with regular cyclists - a
'normal' person will be breathing a _lot_ more heavily).

 

[Chris Slade]

michael adams wrote:

> Surely, experienced commuting cyclists will have already planned
> journeys which avoid roads populated by buses and taxis, as far
> as is possible?

Possibly. When I started commuting from north London into central London
that's exactly what I did. After a couple of months when my fitness
increased a bit, I abandoned the side roads in favour of the main roads in
order to shave a significant amount of time off my journey. I still think
that the pollution I was subjected to was less than if I had been in a car
or on the tube. Can't prove that, but that's how it felt.

--
Chris

 

[Chris Slade]

Tony Raven wrote:

> One interesting thing I found was the worst place for particulate
> inhalation in London was on the tube!
>
http://www.ncbi.nlm.nih.gov/entrez/...d&dopt=Abstract&list_uids=11712603&query_hl=2

I knew I was safer on the roads than on the tube!
--
Chris (being smug, at least for the next ten minutes).

 

[MartinM]

Al C-F wrote:
> wafflycat wrote:
> >
> > "Peewiglet" <[email protected]> wrote in message
> > news:[email protected]...
> >
> >> Did anyone see the article in yesterday's Times? I coudn't see how to
> >> make a link, so here it is.
> >
> >
> > What's the betting the proposed solution is to make the victims change
> > their behaviour, not the actual causes.... move the cyclists away, not
> > decrease the traffic...
> >
> That would be as stated:
> "We need to locate cycle lanes away from major roads."
>
> I wonder if this 'damage' offsets the health benefits of cycling.

Hmm; I watched a Panorama about something similar a few years ago, CO
levels were higher in a car driver than in an un-masked cyclist over
the same distance; but diesel particulates are more likely to get into
lungs in the open air I suppose.

 

[MartinM]

So this is what the BHF spend their dosh on? I hope they tell the 27000
urban cyclists (well urban going out of London and into Brighton) on
the L2B every year.

 

[Phil Cook]

Peewiglet wrote:

>On Sun, 21 Aug 2005 15:13:30 +0100, Phil Cook
><[email protected]> wrote:
>
>>Peewiglet wrote:
>>
>>>Did anyone see the article in yesterday's Times? I coudn't see how to
>>>make a link, so here it is.

>>>Urban cyclists raise their risk of heart disease
>>>Sarah-Kate Templeton, Medical Correspondent

>>And what about walking on city streets or sitting in a bus or car? Do
>>you suppose....
>
>Who? Me? I just reported it, thinking it might be of interest here.

That was a rhetorical plural you, so it wasn't aimed at your good self
in particular.

--
Phil Cook looking north over the park to the "Westminster Gasworks"

 

[Graham Dean]

"Chris Malcolm" <[email protected]> wrote in message
news:[email protected]...
> Peewiglet <[email protected]> writes:
>
>>Did anyone see the article in yesterday's Times? I coudn't see how to
>>make a link, so here it is.
>>-----
>
>>Urban cyclists raise their risk of heart disease
>>Sarah-Kate Templeton, Medical Correspondent
>>
>>
>>CYCLISTS may be doing themselves more harm than good by pedalling to
>>the office along congested roads, according to pioneering research by
>>the British Heart Foundation.
>
>>After just one hour of cycling through traffic, tests showed
>>microscopic particles in diesel fumes caused significant damage to
>>blood vessels, increasing the risk of heart disease.
>
> You get the same extremely small carbon particles, causing the same
> kind of damage, from the candles burning on the table at middle class
> dinner parties.
>

Chris,

Not anymore - that was in the '70s!!

Graham

 

[michael adams]

"Chris Slade" <[email protected]> wrote in message
news:[email protected]...
> michael adams wrote:
>
> > Surely, experienced commuting cyclists will have already planned
> > journeys which avoid roads populated by buses and taxis, as far
> > as is possible?
>
> Possibly. When I started commuting from north London into central London
> that's exactly what I did. After a couple of months when my fitness
> increased a bit, I abandoned the side roads in favour of the main roads in
> order to shave a significant amount of time off my journey. I still think
> that the pollution I was subjected to was less than if I had been in a car
> or on the tube. Can't prove that, but that's how it felt.
>
> --
> Chris

Regardless of the pollution, anything is better than being crushed
on the Tube or stuck solid in traffic in a car, and paying mightily
for the privilige on top, IMO. Simply in terms of avoiding frustration
and a feeling of utter powerlesness to mitigate the situation. Maybe
this becomes more pronounced the longer you use the bike. The station
announcements on the tube nowadays would drive me over the edge
straightaway. To say nothing of the regular cancellations. The side
roads probably offer better air quality, and less stress as compared
with main roads, simply as a result of not having to compete directly
with other traffic. Which can be wearing after a time. Even if it is
at a cost of a longer journey time.


michael adams

....

 

[Tony Raven]

michael adams wrote:
>
>
>
> Regardless of the pollution, anything is better than being crushed
> on the Tube or stuck solid in traffic in a car, and paying mightily
> for the privilige on top, IMO. Simply in terms of avoiding frustration
> and a feeling of utter powerlesness to mitigate the situation.

I wonder too about particulate levels used. For London at least,
traffic is a lot lighter now in the CC zone but all the measurements of
air quality seem to have been made pre-CC.

However with the high levels inhaled also by other road users the best
solution is one for all road users of cutting particulate output of
diesels, not just shifting one group away from the problem and leaving
the rest suffering IMO. And IME the old engines in many of the old
London buses are the worst culprits.
--
Tony

"I did make a mistake once - I thought I'd made a mistake but I hadn't"
Anon

 

[David Hansen]

On Sun, 21 Aug 2005 21:29:23 +0100 someone who may be "Tony W"
<[email protected]> wrote this:-

>Perhaps we should move cars away from people -- they do seem quite
>dangerous!!

I suspect that Mr Newby is a serial motorist and would never even
think about such a thing, laughing loudly if it was suggested and
coming up with all sorts of excuses about why it can't be done.


--
David Hansen, Edinburgh | PGP email preferred-key number F566DA0E
I will always explain revoked keys, unless the UK government
prevents me by using the RIP Act 2000.

 

[David Hansen]

On Sun, 21 Aug 2005 21:01:05 GMT someone who may be Mark Thompson
<[email protected]> wrote this:-

>[1]A cyclist is breathing in air from a much higher point than a car
>driver, and I'd be guessing that the pollution gets worse the closer you
>are to the ground.

A car air intake is also positioned rather closer to the exhaust
outlets of other motor vehicles than a cyclist's mouth.


--
David Hansen, Edinburgh | PGP email preferred-key number F566DA0E
I will always explain revoked keys, unless the UK government
prevents me by using the RIP Act 2000.

 

[David Hansen]

On Mon, 22 Aug 2005 07:01:43 +0100 someone who may be Tony Raven
<[email protected]> wrote this:-

>And IME the old engines in many of the old
>London buses are the worst culprits.

What do you consider "old London buses" to be and how many of them
are there?


--
David Hansen, Edinburgh | PGP email preferred-key number F566DA0E
I will always explain revoked keys, unless the UK government
prevents me by using the RIP Act 2000.

 

[Tony Raven]

David Hansen wrote:
> On Mon, 22 Aug 2005 07:01:43 +0100 someone who may be Tony Raven
> <[email protected]> wrote this:-
>
>
>>And IME the old engines in many of the old
>>London buses are the worst culprits.
>
>
> What do you consider "old London buses" to be and how many of them
> are there?
>
>

There are still a few routemasters scudding around although numbers are
dropping. Most of the fleet are more modern but there are quite a lot
with first registration letters at the low end of the alphabet in
addition to the new fleet and the to be steered clear of bendy buses.

--
Tony

"I did make a mistake once - I thought I'd made a mistake but I hadn't"
Anon

 

[John Hearns]

On Sun, 21 Aug 2005 14:23:12 +0100, Peewiglet wrote:

> Did anyone see the article in yesterday's Times? I coudn't see how to make
> a link, so here it is.

There was a quick item on this on the BBC London TV news this morning.

 

[stupot]

Zog The Undeniable wrote:

>> CYCLISTS may be doing themselves more harm than good by pedalling to
>> the office along congested roads, according to pioneering research by
>> the British Heart Foundation.
> I sense a plot by the Provisional RAC!
Why the RAC?