Cars' tailpipes are nearly as deadly to cyclists as their fenders

April 14, 2016 7:44 PM

Work by University of Toronto researcher Marianne Hatzopoulou "shows cyclists are particularly vulnerable to the risks posed by air pollution — higher levels of breast and prostate cancer being among them. Cyclists, she said, 'tend to have higher breathing rates than other pedestrians, so whatever they’re inhaling is going deeper into their lungs.'" And some of the most popular routes she studied were also the most polluted.

She also created an app for cyclists in Toronto and Montreal to help cyclists plan their routes.

The study and her U of T homepage have lots of additional information.

posted by clawsoon (42 comments total)

Nah, as a Toronto cyclist, I'm pretty sure when my number comes up, it's going to be under a '98 Dodge Grand Caravan with rusted-out body panels, or a 2002 Toyota Sienna.
posted by TheWhiteSkull at 8:07 PM on April 14, 2016 [8 favorites]

It's a real concern, though I always figure being sedentary would probably be worse. I'd love more local data to use in route planning (rather than just the smell test.)

There's a similar study going on in Fort Collins, Colorado. (And that one's not published by goddamn Elsevier.) More about that one here and here.
posted by asperity at 8:13 PM on April 14, 2016 [3 favorites]

I wonder what the per capita ped/bike rate will have to be before this is no longer an issue.
posted by aniola at 8:17 PM on April 14, 2016 [1 favorite]

I asked my doctor this exact question, his opinion was that the health benefits, since sitting is the new smoking, far out weighed the risk potential.
posted by vincentmeanie at 8:21 PM on April 14, 2016 [1 favorite]

vincentmeanie: Last study I saw said the same.
posted by entropicamericana at 8:35 PM on April 14, 2016 [1 favorite]

So I went looking for something to support my vague recollection of having read that local air quality was measurably better on or immediately after my state's annual Bike to Work Day. I only found estimates of reduced emissions based on number of bicyclists and the miles they weren't driving in single-occupant autmobiles, and this: info from air quality monitors mounted on Google Street View cars and driven around Denver for a month.

Unfortunately, that month didn't include our Bike to Work Day. I thought about trying to work this out using archived air quality info from last year's BTWD, but then I remembered that we had a ridiculous tornado monsoon thing for everyone's ride home. That'll probably throw the numbers off. So I tried 2014. I think the numbers for that day looked better but a) I don't really know what the hell I'm looking at, and b) the site started throttling my requests. Guess I'll go back to reading other people's science.
posted by asperity at 8:37 PM on April 14, 2016 [1 favorite]

Actually, the app gave me "straight along Bloor Street" as both the fastest and least-polluted possible route from my home to work, so I'm going to revise my likely cause of death to "doored by a guy in a BMW X5."
posted by TheWhiteSkull at 8:38 PM on April 14, 2016 [12 favorites]

What about city/urban running, then? That would be even deeper breathing, wouldn't it? Yikes.
posted by AwkwardPause at 8:44 PM on April 14, 2016

There was most definitely another study done that showed the health benefits or riding regularly outweighed the downsides of breathing in burnt dinosaur fumes.

Or at least that is what I think about when I'm in traffic.
posted by bradbane at 9:08 PM on April 14, 2016 [1 favorite]

I walk to work alongside the morning traffic. It's actually faster than driving, given the traffic and parking. I wonder how much I'm choking down.

Regardless, I share the road with cyclists and the biggest health risk for them is stupidity. The things I've seen cyclists do, wow, don't worry about the air, worry about that truck.
posted by adept256 at 9:11 PM on April 14, 2016 [1 favorite]

The world needs more off-road cycle paths. I have been fortunate enough to mostly live places where I can do most of my cycle commute off-road - through parks, or along riverbanks or whatever. The few times I've had to cycle regularly along main roads I have really feared for the health of my lungs, even in light traffic.

One place I lived in Australia, I cycled along a busy road for a few blocks and I noticed a not insignificant number of cyclists there wore facemasks, like those little paper ones people use when they have an infectious illness. I can't imagine how annoying that would be to try to breathe comfortably through that while exerting any effort, but I guess the alternative is worse.
posted by lollusc at 10:22 PM on April 14, 2016 [5 favorites]

Grand. Another way car culture is violence against the populace. Negative externalities! Negative externalities for everyone!
posted by Wemmick at 10:32 PM on April 14, 2016 [14 favorites]

Between this and the whole "affects men's genitals by sitting on bike seats" thing, this does not look good for my bike-obsessed town.
posted by jenfullmoon at 10:38 PM on April 14, 2016 [1 favorite]

the app gave me "straight along Bloor Street" as both the fastest and least-polluted possible route from my home to work, so I'm going to revise my likely cause of death to "doored by a guy in a BMW X5

More likely to be killed on College Street. I was doored by a guy getting out of a cab right into the bike lane. Another time I made my son ride ahead of me on that same College St. bike lane so I could see him (safety!) while we were riding to dinner, when some old dude in a Cadillac completely cut him off and almost pinned him into a car. He was obliviously letting his wife out of the car as I zoomed over to make sure my boy was okay, then I screamed at them "you almost fucking hit my son!" The woman sort of sheepishly tried to say sorry but I was shaking as we left. Fucking Toronto.

Also yeah, that pollution stuff is super scary. In the summer it feels like you are dying. I used to commute down Jarvis in the morning and across Richmond coming home and you could really feel it along that Richmond St. stretch.
posted by chococat at 11:23 PM on April 14, 2016 [3 favorites]

It would be cool to have a pollution-measuring gadget you could carry or bolt to your handlebars. Show people how much air crud they are creating and exposing themselves to. I bet there are millions of people who fret over the random cigarette smoker walking by on the sidewalk, but who then calmly expose themselves and their children to loads of secondhand exhaust fumes every day from thousands of cars (including their own).
posted by pracowity at 11:27 PM on April 14, 2016

As someone who rides their bike to work in Toronto when the weather permits, I worry about this in perhaps a similar way to soldiers who smoke during wartime worry about lung cancer.
posted by The Card Cheat at 11:56 PM on April 14, 2016 [14 favorites]

I vaguely re-call reading that the air quality inside vehicles has been shown to be even worse than the air outside (something to do with the air intake for the cabin in most modern vehicles being very low down IIRC), so whilst car drivers may breath less they're getting more pollutants. Not sure which effect wins out frankly!
posted by pharm at 12:36 AM on April 15, 2016 [1 favorite]

vincentmeanie: Last study I saw said the same.

Conclusions
On average, the estimated health benefits of cycling were substantially larger than the risks relative to car driving for individuals shifting their mode of transport.

This is very confusing. Without context, it's a category error to directly compare value ("benefits") and probability ("risks"); this is from basic probability and statistics, which says you can compare expected value, which is value times probability. Why are the doctors phrasing their result like this?
posted by polymodus at 1:47 AM on April 15, 2016 [1 favorite]

Is road traffic in Canada as dominated by (relatively dirty) diesel vehicles, as it is in the UK/EU? The prevalence of diesels, and the increased particulate pollution they cause, has been a sticking point in the UK, with tens of thousands of premature deaths a year estimated to be caused by this pollution. The VW “defeat device” revelations have further brought the issue to the public's attention. There are plans to gradually restrict and phase out the dirtiest vehicles, though they keep getting pushed back (because it's an expense on big business, naturally).
posted by acb at 1:56 AM on April 15, 2016 [1 favorite]

It's worth remembering that the worst place for air pollution is inside a car.
posted by grahamparks at 2:25 AM on April 15, 2016

pracowity: It would be cool to have a pollution-measuring gadget you could carry or bolt to your handlebars. Show people how much air crud they are creating and exposing themselves to.

There is an app called CleanSpace which does this - you buy a little carbon monoxide sensor and link it to your phone, and it tells you about the pollution on your journey and uses the data to make a map of pollution hotspots. And the sensor powers itself over wifi.
posted by penguinliz at 3:44 AM on April 15, 2016 [4 favorites]

For personal cars, diesel is pretty rare is Canada. There are quite a few diesel commercial vehicles but gas dominates for sure.
posted by beau jackson at 4:11 AM on April 15, 2016

I'd imagine the concentration of particles drops pretty rapidly as you get further away from the road so the risk to runners who are not running immediately next to cars is probably much lower. It would be interesting to see how steep the pollution gradient is. If it is this could be a very strong argument for buffered bike lanes.
posted by srboisvert at 5:21 AM on April 15, 2016 [2 favorites]

Yeah, many fewer diesels in Canada than Europe (the stench came back as a reminder when visiting Scotland over the new year) but trucks can — I think — still use the nasty old high-sulfur diesel. The reek from the local school bus depot when those cheesewagons cough themselves into life in the morning is vile.
posted by scruss at 5:41 AM on April 15, 2016

Don't most new cars have hepa air filters? Why doesn't that help with the interior air pollution?
posted by postel's law at 5:53 AM on April 15, 2016

I haven't biked in an urban centre since I got hit by an armoured car with diplomatic plates in downtown Vancouver. The driver stared googly-eyed as I staggered to my feet, then when I made rolling-down motions at the passenger-side window so I could ask him what the actual fuck? he sped off through a red light. I have no idea what he thought I was going to be able to do to him, smear blood on his bulletproof glass maybe.
posted by Mary Ellen Carter at 5:54 AM on April 15, 2016 [3 favorites]

i bought a bike a few weeks ago and biked to work twice this week. Mostly on silent paths paved under high-voltage power lines. Maybe two miles on roads.

I was shocked at how stinky roads still are. I thought that motors had gotten cleaner, but now I wonder if it's just that cars have gotten better cabin air filters.
posted by rebent at 6:38 AM on April 15, 2016 [1 favorite]

Don't most new cars have hepa air filters? Why doesn't that help with the interior air pollution?

Filters can help with particulates, but aren't going to do much for, say, carbon monoxide exposure.
posted by asperity at 7:25 AM on April 15, 2016 [1 favorite]

I could say one thing: air quality in downtown Toronto is a lot better than it was a decade ago. There's a lot that I didn't like about former Premier Dalton McGuinty, but I gotta give him credit for cleaning up air pollution in Ontario.
posted by ovvl at 7:44 AM on April 15, 2016

> I could say one thing: air quality in downtown Toronto is a lot better than it was a decade ago.

This is true. I first moved here in the summer of '98 and I remember getting together for a game of soccer with some friends on a particularly hot and smoggy day, and before long we were all short of breath despite our being young and in pretty good shape. When I got home I blew my nose and the snot was black. Good times. And one summer during the early 2000's a friend's mom flew in to Toronto and said the smog reminded her of Mexico City, which I understand is a a place you do not want your air associated with.
posted by The Card Cheat at 9:09 AM on April 15, 2016 [1 favorite]

postel's law: "Don't most new cars have hepa air filters? Why doesn't that help with the interior air pollution?"

While the filters may be HEPA the rest of the air flow isn't and you can get a lot of leakage. Also cabin filters often only filter recyc air not incoming air. And they won't filter air that leaks in and doesn't go through the filter.
posted by Mitheral at 9:30 AM on April 15, 2016

Remember, though: riding bikes isn't the problem here. Driving is.
posted by entropone at 9:34 AM on April 15, 2016 [4 favorites]

This reminds me of my glory days of being a bike messenger in NYC in the first part of the 80's. It was a weird combination of feeling increasingly stronger, (fantastically strong,) and at the same time subtly poisoned. A mix of unhealthy (sorta kinda) and athletic. Makes me wonder about those French cyclists sucking down the Gauloise to be in training for the smokey velodromes of the interwar years.
posted by Pembquist at 9:58 AM on April 15, 2016

Or, why I tend to wear a wet bandana over my mouth when cycling in LA.
posted by klangklangston at 4:30 PM on April 15, 2016

This is very confusing. Without context, it's a category error to directly compare value ("benefits") and probability ("risks"); this is from basic probability and statistics, which says you can compare expected value, which is value times probability. Why are the doctors phrasing their result like this?

This is not an error: "benefit"/"risk" in this context refers to decreases/increases in relative risk of death from all causes.
posted by en forme de poire at 7:44 PM on April 15, 2016

Sure, relative risk makes more sense. Yet while the wikipedia entry is clear and precise, whereas the original sentence, is nonsensical:

On average, the estimated health benefits of cycling were substantially larger than the risks relative to car driving for individuals shifting their mode of transport.

What this sentence grammatically says is: a) compare ("larger") the health benefits of cycling with the health risks of cycling; b) oh, but let's relativize that to car driving (since we have data on individuals who switch from one to the other).

But that seems to be stating something way more complicated, and vague/incomplete, than a relative risk calculation. I'm not doubting the analysis; I think this is a mild case of poor verbal math.
posted by polymodus at 5:40 AM on April 16, 2016

No, what they're saying is clear. "Relative to car driving for individuals shifting their mode of transport" refers to both the benefits and the risks. If you found this sentence unclear, I guess because you wanted there to be a comma between "risks" and "relative," you could have also looked at the previous paragraph in the abstract, in which it is unambiguous that both benefits and risks are measured relative to driving and are measured on the same scale:

We have expressed mortality impacts in life-years gained or lost, using life table calculations. For individuals who shift from car to bicycle, we estimated that beneficial effects of increased physical activity are substantially larger (3–14 months gained) than the potential mortality effect of increased inhaled air pollution doses (0.8–40 days lost) and the increase in traffic accidents (5–9 days lost).

posted by en forme de poire at 3:40 PM on April 16, 2016

It would be cool to have a pollution-measuring gadget you could carry or bolt to your handlebars. Show people how much air crud they are creating and exposing themselves to. I bet there are millions of people who fret over the random cigarette smoker walking by on the sidewalk, but who then calmly expose themselves and their children to loads of secondhand exhaust fumes every day from thousands of cars (including their own).

I used to work for air quality scientists who measured these sorts of things and living in a house on a major road is as bad as being a multi-pack-a-day smoker.
posted by Jacqueline at 5:43 AM on April 17, 2016 [1 favorite]

Jacqueline: I used to work for air quality scientists who measured these sorts of things and living in a house on a major road is as bad as being a multi-pack-a-day smoker.

I'm remembering something - vaguely - about scientists who tried to find out if the "living near high voltage lines is unhealthy" thing is true, and what they ended up finding was that it was true only so long as the high voltage lines were next to freeways (which they often are). Whenever the high voltage lines and the freeways diverged, all the bad health effects followed the freeways.
posted by clawsoon at 4:44 PM on April 17, 2016 [2 favorites]

It really is breathtaking (heh), the number of ways cars are killing us, isn't it? Crashes, air pollution, noise pollution, inactivity, climate change.. To say nothing of the destruction of greenfields to support autocentric growth and all the social and economic impacts of autocentric development.
posted by entropicamericana at 6:23 AM on April 18, 2016 [1 favorite]

More good health news about cars!

The findings suggest that those who live within 1,500 feet of a highway have a greater likelihood of developing cardiovascular disease than those living twice as far away. More than 45 million Americans live within 900 feet of a major road, railroad, or airport, according to the US Environmental Protection Agency... Even relatively brief exposure — just months or days — can elevate health risks, they said.

posted by entropicamericana at 6:18 AM on April 19, 2016 [4 favorites]

Huh. Yet somehow health insurance companies are nagging subscribers to wear fitbits instead of lobbying for cleaner energy. Go figure!
posted by Salamandrous at 3:35 PM on May 14, 2016 [1 favorite]