Traffic found to be a major source of atmospheric nanocluster aerosols

July 4, 2017 by Bob Yirka report
Credit: CC0 Public Domain

(Phys.org)—A team of researchers affiliated with several institutions in Finland has found that automobile traffic can be a major source of atmospheric nanocluster aerosols. In their paper published in Proceedings of the National Academy of Sciences, the group describes how they obtained air samples from several locations in Helsinki and elsewhere and looked for extremely small traffic-originated nanocluster aerosol (NCA) particles and what they found by doing so.

Most everyone knows that automobiles emit pollution, which consists of like soot and gasses such as carbon dioxide and carbon monoxide. The result in congested areas is dirty air, which besides being unsightly, is also harmful to health. But as the researchers with this new effort note, less is known about the extremely tiny particles that are also emitted into the air from cars and trucks.

To learn more about such tiny particles, the researchers collected air samples near roadways under various conditions in Helsinki and other spots throughout Europe. They then tested the air samples for both the tiny particles and the nanoclusters that are formed when they combine with other particles. Tiny particles in the air, they note, as well as nanoclusters, come from a variety of sources, not just traffic. They can be emitted by factories, and in many cases, from natural sources such as plants. To separate other sources from those created by traffic, the researchers compared from the same places when the wind was blowing in different directions.

In looking at their data, the researchers report that they found a significant amount of NCA particles with a diameter range of 1.3 to 3.0 nm in urban air near heavily trafficked areas. They also found that a significant portion of the particles were a direct result of traffic, as opposed to other industrial or natural emissions. To show this was the case, they offer statistics such as finding that approximately 20 to 54 percent of NCA particles in a semi-urban roadside site came from emissions.

The researchers note are more difficult to study because of their short-lived nature—they bind to other particles and often wind up as part of water droplet formation in the atmosphere. They further note that the smaller the particles, the easier it is for them to make their way deeper into lung passages, causing unknown health problems.

Explore further: Unique model tagging technique identifies soot's pollution source over China

More information: Topi Rönkkö et al. Traffic is a major source of atmospheric nanocluster aerosol, Proceedings of the National Academy of Sciences (2017). DOI: 10.1073/pnas.1700830114

Abstract
In densely populated areas, traffic is a significant source of atmospheric aerosol particles. Owing to their small size and complicated chemical and physical characteristics, atmospheric particles resulting from traffic emissions pose a significant risk to human health and also contribute to anthropogenic forcing of climate. Previous research has established that vehicles directly emit primary aerosol particles and also contribute to secondary aerosol particle formation by emitting aerosol precursors. Here, we extend the urban atmospheric aerosol characterization to cover nanocluster aerosol (NCA) particles and show that a major fraction of particles emitted by road transportation are in a previously unmeasured size range of 1.3–3.0 nm. For instance, in a semiurban roadside environment, the NCA represented 20–54% of the total particle concentration in ambient air. The observed NCA concentrations varied significantly depending on the traffic rate and wind direction. The emission factors of NCA for traffic were 2.4·1015 (kgfuel)−1 in a roadside environment, 2.6·1015 (kgfuel)−1 in a street canyon, and 2.9·1015 (kgfuel)−1 in an on-road study throughout Europe. Interestingly, these emissions were not associated with all vehicles. In engine laboratory experiments, the emission factor of exhaust NCA varied from a relatively low value of 1.6·1012 (kgfuel)−1 to a high value of 4.3·1015 (kgfuel)−1. These NCA emissions directly affect particle concentrations and human exposure to nanosized aerosol in urban areas, and potentially may act as nanosized condensation nuclei for the condensation of atmospheric low-volatile organic compounds.

Related Stories

Sea traffic pollutes our lungs more than previously thought

November 20, 2015

New data presented by researchers at Lund University and others in the journal Oceanologia, show that the air along the coasts is full of hazardous nanoparticles from sea traffic. Almost half of the measured particles stem ...

Recommended for you

The world needs to rethink the value of water

November 23, 2017

Research led by Oxford University highlights the accelerating pressure on measuring, monitoring and managing water locally and globally. A new four-part framework is proposed to value water for sustainable development to ...

'Lost' 99% of ocean microplastics to be identified with dye?

November 23, 2017

The smallest microplastics in our oceans – which go largely undetected and are potentially harmful – could be more effectively identified using an innovative and inexpensive new method, developed by researchers at the ...

13 comments

Adjust slider to filter visible comments by rank

Display comments: newest first

MR166
1 / 5 (3) Jul 04, 2017
Meanwhile, life expectancy continues to increase so what is the point of the research other than to condemn fossil fuels? If you happen to be wondering why the western economies are almost bankrupt perhaps people doing useless work are part of the answer.
betterexists
not rated yet Jul 04, 2017
Tesla's All-Electric-Semi-Trucks coming in September leading to a Very Rapid Transition into Economics Driven Truck Industry, Where COST Really Matters even To the Very Last cent ! Going to be Very Disruptive to the Currently ongoing Industry!
Some Doubt it because of Big Battery Sizes. I say Leave Batteries on the way in Gas Stations. Keep Pushing out Old ones and Pushing in New ones at intervals.
This is Robotic Age!
RealityCheck
3 / 5 (4) Jul 04, 2017
MR166.
Meanwhile, life expectancy continues to increase so what is the point of the research other than to condemn fossil fuels? If you happen to be wondering why the western economies are almost bankrupt perhaps people doing useless work are part of the answer.
That's you being 'one eyed' again, MR166; explicitly omitting many of the OTHER determinants of life expectancy; namely: health care, medicine, better life/work styles/cnditions verall, better social security/safety-net by govts/society and so on.

So if you actually were honest about it, you would realize that better life expectancy has come DESPITE all the pollution/damage associated with pollution/costs incurred using fossil fuels.

The above article points to that very pollution caused by fossil fueled cars! On top of pollution caused by fossil fueled power plants, MR66.

Please in future be more OBJECTIVE when considering/commenting re especially IMPORTANT issues, ok, MR166? Thanks. :)
betterexists
not rated yet Jul 04, 2017
Tesla's All-Electric-Semi-Trucks coming in September leading to a Very Rapid Transition into Economics Driven Truck Industry, Where COST Really Matters even To the Very Last cent ! Going to be Very Disruptive to the Currently ongoing Industry!
Some Doubt it because of Big Battery Sizes. I say Leave Batteries on the way in Gas Stations. Keep Pushing out Old ones and Pushing in New ones at intervals.
This is Robotic Age!

Send a Regular Truck with Charged Batteries to be dumped on the way, for Electric Semi-Trucks to use them. Initially, All Truck Cos should work together on this!
MR166
1 / 5 (2) Jul 05, 2017
Reality Check the point that you refuse to admit is that fossil fuels play a huge role in our increased lifespan. They feed and house us. One person estimated that fossil fuels provide every person with the equivalent labor of 100 slaves. The the net contribution of fossil energy far outweighs any harmful effects. Papers like this are just propaganda intended to create hysteria.
MR166
1 / 5 (2) Jul 05, 2017
The biggest threat that mankind faces is running out of the cheap oil and gas. We are very lucky that fracking is so successful in the US. Otherwise oil prices would be double or triple today's prices and the US would be deep into depression. 10s if not 100s of millions more would be hungry, homeless and in poverty.
antialias_physorg
5 / 5 (3) Jul 05, 2017
Why do we even find it acceptable that city air is more polluted than air in the countryside? Particularly when through the use of technolgy (e.g. using electric vehicles) it doesn't need to be?
MR166
1 / 5 (1) Jul 05, 2017
I have no problems with electric vehicles. They are a great idea for some drivers. In the not to distant future they will be suitable for most drivers. The grid and generating facilities need to be seriously upgraded before that is possible. I just am against taxing the general population in order to make all of this happen.
MR166
1 / 5 (1) Jul 05, 2017
Before the invention of fossil powered vehicles pollution in the cities was a major health problem. Animal excrement and the associated flies were a serious health problem. I imagine that the smell had to be pretty bad also i.e. air pollution.
greenonions1
5 / 5 (1) Jul 06, 2017
MR
Meanwhile, life expectancy continues to increase so what is the point of the research other than to condemn fossil fuels?
What is wrong with studying our world - and if there is a problem - pointing it out? MR166 supports the dumping of thousands of tons of toxic coal ash into land fills - that pollute the environment - and raise the risk of cancer - http://bittersout...BuemQyM-
If we could find a viable alternative to fossil fuels - that has less of an environmental impact - and still give us the benefits of abundant energy - that would be a win/win right? Developing win/win ideas - requires critical thinking.
betterexists
5 / 5 (1) Jul 06, 2017
No more Petrol, Diesel vehicles in France by 2040
US has Deviated!
RealityCheck
2.3 / 5 (3) Jul 08, 2017
@MR166.

No argument that fossil fuels have been instrumental in many humanity-friendly advances as a cheap energy source, especially for heating, cooling and machines replacing much household/industrial labor previously the lot of house/industry 'slave' and 'wage-slave' labor. But, MR166, that does not mean we should keep using them to the same extent forever if we can avoid the downsides mentioned earlier, does it? We can feasibly (economically/technically) wean off much of fossil dependency with renewable alternatives.

Further points:

Extreme acid rain damage from fossil fuels (since pre-industrial age), to statues/buildings which have stood for hundreds/thousands of years before then, dramatically demonstrates high costs/effects of fossils pollution.

If materials technologies advance as at present, SUPERCONDUCTING ring systems will probably overtake chemical batteries/gravity storage systems for renewable energy storage/smoothing, sooner than later.

Ok, MR166? :)
Captain Stumpy
5 / 5 (1) Jul 09, 2017
@mr
Meanwhile, life expectancy continues to increase so what is the point of the research other than to condemn fossil fuels?
think how much longer they would live if they weren't being polluted
perhaps people doing useless work are part of the answer
since when is any fundamental research useless?
perhaps you just can't see the potential for said research, and i know you don't agree with research in areas where you have a cognitive bias against reality (climate change), so who, then, should choose which direction research goes in?
you?

if people like you chose the direction, we would still be riding horses and we would still believe heavier than air flight is impossible because you ignore the reality proven by experimentation and solid research

case in point, your comment
fossil fuels play a huge role in our increased lifespan
or - the "supplement delusion" argument

iodine is required for life too
you should double your intake because it's good

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.