Can Air pollutants negate health benefits of cycling in city urban centres??

sxt

I know that this is less of a problem than 10 years ago with more and more electric vehicles etc but with there is still a high percentage of diesel vehicles in Ireland...

magicbastarder

cyclists are exposed to better air quality than occupants of cars stuck in traffic - this is a well tested issue AFAIK and in a city like dublin, the answer to the question in the thread title is a definite no.

mazdamiatamx5

Seriously?

CramCycle

Plenty of published evidence to say this is not the case. The electric vehicle idea aside (to few to be have made a difference with an increase in numbers of other motorised vehicles). Modern cars pollute less and less in the immediate environment but again, doesn't really make a difference in somewhere like Ireland.

TLDR: No, air pollutants (in Ireland) do not negate the benefits of cycling.

magicbastarder

you're asking me? yes, seriously.

https://www.theguardian.com/environment/2016/may/05/benefits-cycling-walking-outweigh-air-pollution-risk-cities

sxt

https://www.boards.ie/discussion/comment/120888543#Comment_120888543

If you are stopping at traffic lights every 500 yards and inhaling diesel fumes, It has to be a lot healthier to cycle in a non Urban/ non congested area etc

magicbastarder

yes, but that wasn't your question.

CramCycle

https://www.boards.ie/discussion/comment/120888572#Comment_120888572

That wasn't the question, you've set the query, respect it. A fairer, more sensible query would be " in a scenario where you are stopping every 100m, is cycling or driving healthier?"

Evidence points to one, guess what it is.

sxt

https://www.boards.ie/discussion/comment/120888785#Comment_120888785

I presume cycling

But if you are a cylist and breathing in diesel fumes every 100m , there has to be a health concern or not?

Dial Hard

https://www.boards.ie/discussion/comment/120888848#Comment_120888848

Again, not the question you asked. Why are you being so obtuse?

sxt

https://www.boards.ie/discussion/comment/120888852#Comment_120888852

My question hasn't changed at all

I believe cycling in urban areas isn't as healthy as it could be , as it should be ,or as it is portrayed to be

You are taking in 3 times the air when you are cycling compared to walking, hence 3 times pollutants

It would be alot more healthy if you walked

Mellor

https://www.boards.ie/discussion/comment/120888848#Comment_120888848

What air do you think the people is cars are breathing? Or people standing at the lights beside the cyclists. You aren't really comparing to anything, looking at one in isolation is a bit pointless. To harmless if something is bad or worse, you need to establish a counterfactual or banchmark.

But the short answer yes, at a certain point, if pollution is high enough cycling long durations daily could cause more harm that good. That duration is likely to be extremely long in Ireland, far longer than you would cycle.

https://www.boards.ie/discussion/comment/120888897#Comment_120888897

You take in 3 times the air when cycling? By what unit. Have a little think about that it it might change you "hence more pollutants" conclusion.

Peregrinus

Cyclists and motorists on the same streets breathe the same air, and are exposed to the same pollutants. But because cyclists are engaged in moderate physical exercise their metabolic rate is higher, and they process those pollutants more effectively. (Same goes for runners and people engaged in brisk walking.)

Even if it is true that cyclist take in three times the air that motorists do (and I've not seen that attested, but let's assume it is true) this doesn't just mean three times more pollutants; it also means three times more oxygen, etc. The concentration of pollutants in the air they breathe is unchanged, but their capacity to deal with it is enhanced.

o1s1n

https://www.boards.ie/discussion/comment/120888897#Comment_120888897

You are forgetting time and length of exposure.

It would take me about 40-50 minutes to walk through the city centre on my commute to work. Beside the road, breathing in car fumes the whole time.

The equivalent part of my cycle takes me about 12-15 minutes.

Weepsie

https://www.boards.ie/discussion/comment/120888572#Comment_120888572

Unless you're quite literally down at the exhaust, you're fine

Weepsie

https://www.boards.ie/discussion/comment/120888897#Comment_120888897

You believe all you want, but you're wrong.

Pigeon Reaper

https://www.slideshare.net/JamesTate22/exposure-to-the-trafficrelated-air-pollutants-particle-number-and-no2-when-commuting-by-modes-walk-cycle-car-and-bus

Here's just one of many peer reviewed scientific studies on this subject everyone can read.

https://ij-healthgeographics.biomedcentral.com/articles/10.1186/s12942-021-00272-2

Another study this time based in Delhi.

US based one at "https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4893018/"

Candaian one. "https://iopscience.iop.org/article/10.1088/1748-9326/ac1379"

Tenzor07

https://www.boards.ie/discussion/2058306183/can-air-pollutants-negate-health-benefits-of-cycling-in-city-urban-centres

Whilst Electric vehicles may be "Zero emissions" at the exhaust pipe, they emit particulates from tyres and brake pads, and the fact that most EV's weigh about 400 to 500kg+ more than an Ice equivalent... So all those particulate can end up in the lungs...

zg3409

https://www.boards.ie/discussion/comment/120893076#Comment_120893076

This is a total exaguration. One study I read claimed more was emitted than the entire rubber in the tyre. These particles are heavy and they fall to ground and get washed away. Also rubber is not hazardous.

EVs use less brakes and my EV has same brake pads after 100,000km.

Exhaust fumes are bad particularly when cars engines are cold, but again cycling is far better for your lungs than any damage caused. Naturally try stay away from exhausts at traffic lights but the health benefits far outweigh any risks.

Tenzor07

https://www.boards.ie/discussion/comment/120893111#Comment_120893111

Not going to be dragged down the rabbit hole of EV's versus ICE cars, needless to say there is such a thing called "non-exhaust emissions" and heavy EV's emit them.

increasingly stringent standards regarding the PM content of exhaust emissions, non-exhaust emissions are quickly becoming the dominant source of PM emissions from road traffic, and are expected to comprise the vast majority of all PM from road traffic as early as 2035. While the uptake of electric vehicles (EVs) will contribute to reducing exhaust PM in future years, non-exhaust PM will not noticeably fall unless targeted policies are undertaken.

kirving

It is worth noting that cars use fairly large cabin air filters, so it would be reasonable to assume that particulate matter concentration inside a vehicle is less than outside.

It obviously filters much more air than I breath in, but it's usually fairly filthy when I change it.

magicbastarder

not so sure about that.

https://www.theguardian.com/environment/2017/jun/12/children-risk-air-pollution-cars-former-uk-chief-scientist-warns

pollutants build up inside a car, from what i have read - you could cycle through an oily cloud of exhaust and be through it in a second - but your car will suck it in and hold it inside the car for possibly minutes.

DownByTheGarden

Working in big data for decades myself im fully aware that i can get a study done to say any result i want, opposite sides of any argument - using the same dataset - at least until next week when im finished working - yippeee

So im not going to go linking to articles because we can all find ones that contradict each other depending on the source of them

So, I can only tell you what I feel.

When im cycling im breathing in deep and heavy. I can feel the pollutants going down my throat and deep into my lungs. I can taste it.

When im driving im relaxed and not breathing deep or heavy. I usually have the windows closed too and the Ac on when in traffic. There is a filter between me and the air. What it fitlers out i dont know, but i can tell myself the difference in the taste and feeling in my lungs between being in the car and cycling in the city.

o1s1n

https://www.boards.ie/discussion/comment/120893313#Comment_120893313

Where are you cycling through, a smog riddled city in China?

I cycle right through Dublin city centre twice a day every day in peak time traffic and over to the N11, which I continue along all the way out to the outskirts of Dublin.

The only time I feel what you are talking about is if I'm stopped in traffic behind someone who has a ruined exhaust on their car. Which is very very rare.

DownByTheGarden

https://www.boards.ie/discussion/comment/120893587#Comment_120893587

You are probably just used to it so dont notice it. Most of the time I cycle outside the city. When I cycle in the city it is very, very noticeable.

Kind of like a smoker going into a smoky room with someone who doesnt normally smoke. Only one of them is going to notice the smoke they are breathing in.

o1s1n

https://www.boards.ie/discussion/comment/120893800#Comment_120893800

I'll give it a 'taste' on the way home and see what you mean. 😁

I still think time spend is a very important factor though. Doesn't matter what the traffic is like, I'll be through the city centre on my bike in about 15 minutes.

I've sat in traffic on the same commute along the quays for 40 minutes plus. So exposure time is far longer. You can definitely smell fumes and the likes when sitting on a bus or in traffic in the summer with your car windows open.

As an aside, I'd be a bit worried about someone's health if they were breathing 'deep and heavy' while cycling through the city. You can't exactly go relatively fast with the traffic and Dublin city is very flat. I'll monitor my breathing rate on the way home but I don't think it's particularly laboured when I actually hit the city centre and have to start slowing down.

Paddigol

I cycle from the countryside into the city centre at least a couple of days a week most weeks. Can't say that I've ever noticed an issue with filthy air being inhaled, other than when I'm behind a car/ truck/ bus that has a visibly defective exhaust. That said, I rarely notice anything in the car either. I don't think I'm going to convince you that you're not tasting pollution any more than you're going to convince me that I am inhaling it. And since we're not referencing any data/ studies, I guess the debate is over.

The question isn't "is it healthier to cycle down the quays or over the wicklow mountains" and it's not "is air quality in dublin city centre optimum for recreational cycling". I just can't accept that "air pollutants negate health benefits of cycling in city urban centres".

CramCycle

Works in big data but doesn't like what the data says. All of the studies pretty much agree with each other. Varying levels of the same thing. The BMJ one is one of the most comparable to living in Ireland as it's from UK data.

The question was can air pollutants negate the health benefits of cycling. As a scientific question there are huge issues so I will clarify a few assumptions. One, it's an Irish city, so not a highly polluted one compared to a small number that are actually dangerous to your health just by being there. Two, that it is a fair comparison, so it's either against pedestrian or motorist, or its against being in the city in general.

For an Irish city like Dublin, the BMJ paper (based from UK data, so highly comparable) which has a huge amount of data points implies that regular cycling reduces all cause mortality quite significantly.

Compared to driving or walking, evidence implies for your health that cycling regularly (when it has to be in a city) is better for your health than not regularly cycling (or not cycling at all). For the other, if you are comparing rural to urban, I am not sure on the all cause mortality reduction but the air pollution would be reduced but I'm not sure that's fair as there, in many scenarios, unlike your transport choice, there is very little choice on whether you live in an urban or rural location.

DaveyDave

This is a very interesting question. You're spending less time on a bike but you're breathing more. No matter where I go whether it's commuting or a leisurely spin on the ebike I'm always going around 60-70% effort and breathing a fair bit more than when walking.

When walking I'm also not stuck behind a vehicles exhaust fumes. Cars generate 15-20kg of CO2 per 100km plus NOX and all other chemicals.

Plenty of older diesels on the roads in Ireland, lots of them emitting black smoke. Diesels on our roads account for twice as many new sales as the EU average.

A car isn't breathing in the same fumes because they have carbon filters in the climate system. Maybe not HEPA quality but better than nothing.

Whatever fumes you do breathe in I'm sure the physical benefits of cycling nore than make up for it.

Weepsie

https://www.boards.ie/discussion/comment/120894313#Comment_120894313

Works in big data but goes by vibes

Flinty997

https://www.boards.ie/discussion/comment/120894582#Comment_120894582

A car is breathing in MORE fumes because it takes in air from in front. What's in front but the exhaust of the vehicle in front. It's literally got an intake fan sucking and funnelling it into the cabin. Most cars don't filter out the really bad stuff. What's more someone in a car is mostly likely to be sitting in traffic longer than other forms of transport.