How Does Pollution Affect Cyclists?
by Matthew Sparkes, London, UK on 03.19.07
By cycling instead of driving or taking public transport, you are doing your part to keep the air clean. The problem is that you have to cycle through all the pollution created by people who aren't making any effort.
Pollution has been linked to heart and lung disease, and people often complain of other less serious reactions such as sore-throats, coughs and stinging eyes. I have often noticed that if I cycle a few miles in London in a white t shirt, it picks up lots of black particulates.
It's impossible to quantify the pollution level for a city in any simple way, because the level of pollution varies from area to area, and will change over time. The type of contaminants found in a certain area can also vary, and each one causes different health problems. Weather and temperature also affect how much of an effect pollution will have. On windy, cold days, a certain road will be safer to bike through than on a still, warm day. This is probably a good thing, because we have a lot of windy, cold days in London.
You breathe much heavier when cycling, so you inhale more polluted air than normal. One partial solution is to avoid congested roads, which should reduce the amount of fumes you are exposed to. However, in a busy city like London this isn't always possible. Another possibility is to wear a pollution mask, but the protection they provide varies.
You will notice if you look at the websites of companies which sell masks that they rarely make any quantified claims about effectiveness, and some never explicitly claim to protect you against pollution at all.
'Health Which?' magazine conducted a study that compared the protection offered by several types of mask, you need to register to read it, but helpfully the BBC have posted a summary. Bizarrely, the cheapest mask on offer, the Kanco Eezy Breethe, performed the best. Other, more expensive masks failed to filter out the poisonous chemicals.
Overall though, the benefits you gain from cycling and keeping healthy should outweigh the negative aspects of breathing in the fumes. Everyone in a large city is exposed to a certain amount of pollution, including people inside vehicles, and you can't travel without breathing in something nasty. Of course, if everyone cycled to work then we wouldn't have this problem…
Be aware that the BBC study cited is from 1998. Re-testing of cycling masks is long overdue.
It helps to understand that pollution dispersion is strongly controlled by two factors readily observable: surface roughness and atmospheric stability. At one roughness extreme is a flat paved landscape (promoting dispersion). The other is an urban core with buildings and cars and fences (slowing dispersion). At one stability extreme is a clear windless early morning with high temp. At the other is a gusty dry sunny mid-day. It is not a coincidence that the highest ground level ozone levels are found right after sunrise, when atmospheric stability is highest.
Heavier breathing might increase the dose, although not necessarily as the changes in airflow patterns means an increase in breathing does not necessarily result in proportionately increased (micro-)particle deposition.
A number of studies show that the air to which motorists are exposed has significantly higher pollutant concentrations than the air cyclists are exposed to. This makes sense when you consider that the air intakes into cars are closer to the exhaust pipes of other cars than the air intakes of cyclists. Additionally, there are all kinds of complicated factors to do with deposition and recirculation of particles.
My experience in London is that anti-car measures move people onto mopeds and motorbikes rather than onto bikes or public transport.
"Why can I smell a moped 100meters away whereas evil 4x4s etc are inconspicuous?" I often think
A little research shows that 2-wheels are awful pollutors even if they are more carbon friendly
EU environmental standards for 2-stroke and 4-stroke motorbikes are more lax than countries such as India, Japan and China. (allowing 200-700% more carbon monoxide and hydrocarbon emissions. World bank believes that 2-stoke engines may be phased out in south-east asia due to environmental concerns.
http://www.worldbank.org/transport/urbtrans/e&ei/2str1201.pdf
The test result revealed that average benzene concentrations in exhaust emission for the test motorcycles ranged from 3.02 to 109.68mg/m3. The finding also indicated that two-stroke motorcycles emitted five times more benzene than that of four-stroke motorcycles
Authors: Leong S.T.1; Muttamara S.; Laortanakul P.
Source: Atmospheric Environment, Volume 36, Number 4, February 2002, pp. 651-661(11)
Publisher: Elsevier
DOT's statistics show that motorcycles averaged between 43 and 50.0 mpg. This has not increased since 1970. Cars averaged 25mpg, an increase of 70% since 1975
http://www.epa.gov/OMSWWW/models/mobile6/p02005.pdf
Yeah, mopeds definitely need to be cleaner. I think it's starting to happen here in Canada.
Some will say it's a cost issue. It costs a bit more to make a cleaner engine.. But having a polluted city also has costs. Maybe it would be possible to give a rebate on less polluting mopeds (or just regulate..). Hmm.
Cyclists do not breathe more pollutants than motorists, as this study shows.
Cyclists are breathing cleaner air because they are relatively high up - by comparison the air in cars is drawn in from ground - and exhaust - level.
Cyclists also breathe more heavily - even if not cycling hard - meaning fewer particulates etc settle in the lungs.
Also, that link about pollution and heart disease is dodgy. Newby's much-vaunted paper doesn't seem to have surfaced and the link between cycling, pollution and poor health is, in the words of the British Heart Foundation, "yet to be directly proven."
It is true that cyclists don't breathe more pollutants than car drivers do, and I don't think this post was saying that (just follow the first link in the post).
Just saying that when you are in a polluted city, you should be careful about what you breathe, and that's quite true. I guess some european cities can have more problem with diesel than some other places.. Hopefully cleaner diesel engines will help with that.
Cars also give off air pollution from the plastic finishes inside. Sick car syndrome.
SteveL, you are right. check this out:
http://www.treehugger.com/files/2005/09/beware_that_new.php
Correct in many cases.
What is I am not sure, I just feel agreeable today.
I ride a bicycle to work along under route 278 on 3rd Avenue from Brookyn to NYC. This part of the ride is about 5 miles. Most of the time it's through idling trucks, cars, buses etc. My biggest worry is carbon monoxide. I believe it is heavier than air and it should settle. I have an elevated highway above me and parked cars to my side. I usually feel great after the ride (about 11 miles one way). But maybe something is insidiously attacking me??
I use glasses all the time, the wind and dust is too much otherwise.
My 1991 Honda Nighthawk 4 cylinder air cooled motorcycle gets about 44 mpg at 60-65 mph. Right on with what an earlier poster said about motorcycles' economy. I keep it in good tune, it has about 32K miles on it. My older and bigger Harley got roughly the same mpg.
Yes, it is peculiar that the bikes don't return better mpg given their size, etc.
I think two strokes for the street won't be around much longer. The power to weight ratio is better than 4 strokes, but 4 strokes foul plugs much less and are just more pleasant to ride given the lower noise output and not having to mix oil with the gas.
Anyway, as I looked out the subway window I could see that they plowed the snow off the Manhattan Bridge bike path... I could have saved myself $4.oo
Good luck,
vsk
Yes, "new car smell" is really just VOCs from the large amounts of vinyl, glues, finishes, foams, etc. used to make car interiors. I'll opt for the polluted air outside any day.
Older mopeds were largely 2-strokes; new ones are pretty much all 4-stroke (in the US) which means much less pollution. I am not sure about the UK, though I believe laws are somewhat more lax.
Motorcycles in the US now are required to have a catalytic converter,though frequently people take theirs off for performance. I'm not sure about mopeds / scooters though. The move to two-wheelers is generally positive as the newer bikes they're buying are relatively clean and not the foul smell-emitting 2-smokers of yore.
I ride my bicycle to work every day. I used to live in NYC and am now THRILLED to live in San Francisco, where most of the busses are electric and get power from wires suspended over the street. At first I thought they were unsightly, but now i love them unconditionally. I excitedly told my dad about the great, non-polluting busses and he said, "but how do you think they get the energy for the wires, from fairy dust? There's pollution definitely somewhere!"
it was around then that i punched him in the face and smoked a pack of cigarettes.
""Why can I smell a moped 100meters away whereas evil 4x4s etc are inconspicuous?" I often think"
Thats because of a moped uses a 2 cycle engine, not a 4. It's got nothing to do with the amount of pollution it's causing.
I ride to the train and take that (electric) train into the city and then ride from there to my office and I have never noticed any problem.
-Side note I there there is too much advertising on this site. Makes it look like this is just a way to make money rather than actually addressing the issues. Especially the navigational links at the top left of the site.
I think we should consider the possibility of using a small O2 tank in our backpacks. Camelback would make big bucks with a product like this. Refilling the tank is question number 2.
Ride safe. Cheers.
Luckily when I bike to work it is down a bike path for 90% of the way. No cars are nearby.
I have tried the charcoal mask shown in the pic above. It was useable, but after riding hard, I would have a weird sensation in my throat, like I'd just been breathing some weird chemicals...that lasted for hours after riding. Also, they get wet in cold conditions and dont move enough air when really cranking.
My approach now is to just back off the effort when riding next to cars, once i get to cleaner areas with less cars I cank up the output and that seems to help. I dont use the mask anymore. Hopefully I wont die of lung cancer anytime soon.
8^)
I wore a mask for a while, but thought the loss of communication with motorists was more dangerous to my health than breathing the fumes - people respond to seeing a person's (whole) face. They gave me more space, respond to signals more readily etc. I don't think this was just my imagination!