[floydarogers]

http://www.bbc.co.uk/news/resources/...ur_car_exhaust

It's a long article (and I hate the formatting), but it's quite telling. The EU has totally failed in emissions testing: modern diesels, even with BlueDef etc., all miserably fail EU6 standards. No wonder the TDI scandal happened. The US/CA is probably a bit better because they have three different regimes they're testing using the dynamometer.

[robnitro]

The problem is that they are blaming too much on NOx, when it has been shown that in California, smog increases on the weekends when there is much less industrial (diesel) equipment and more gasoline on the roads.

NOx is a sign of compete, lean combustion: meaning there is almost zero carbon monoxide and less particulates. Adblue is a good idea, but implemented badly to be long term reliable as we have seen on 35d engines, and the craze of using a lot of egr also creates other issues like particulates and our beloved CBU.

There was an article someone posted about how dpf's emit smaller, more hazardous to health particles than the original exhaust, but I can't find the link now.

[fsd350]

Originally Posted by robnitro

The problem is that they are blaming too much on NOx, when it has been shown that in California, smog increases on the weekends when there is much less industrial (diesel) equipment and more gasoline on the roads.

NOx is a sign of compete, lean combustion: meaning there is almost zero carbon monoxide and less particulates. Adblue is a good idea, but implemented badly to be long term reliable as we have seen on 35d engines, and the craze of using a lot of egr also creates other issues like particulates and our beloved CBU.

There was an article someone posted about how dpf's emit smaller, more hazardous to health particles than the original exhaust, but I can't find the link now.

I have also read that the DPF increases cancer risk. You can't really burn carbon, it creates smaller particles of soot more readily absorbed by eyes, skin and lungs.

[Adieu]

EGR and DPF just rearrange regulated particle sizes into something smaller and more dangerous --- but not measured by the testing regime and therefore not regulated

Shameless and counterproductive gaming of our imperfect emissions regulations

[kwaked]

Another thing worth considering before writing off DPF's is that it has been shown that PM10 pollution has a significantly higher risk to people within 100m of a major road..

The point of a DPF is not to dramatically reduce PM10 it's to carry out controlled burn in less densely populated areas

This makes a significant health difference to those that live in cities

[rbreding]

Originally Posted by kwaked

Another thing worth considering before writing off DPF's is that it has been shown that PM10 pollution has a significantly higher risk to people within 100m of a major road..

The point of a DPF is not to dramatically reduce PM10 it's to carry out controlled burn in less densely populated areas

This makes a significant health difference to those that live in cities

Just so I make sure I understand you right. Our diesels know when they have left the city and initiate a regen when in rural areas?

[TDIwyse]

People get very hung up on "tail pipe" emissions, but that's no longer the major source of PM10 or other particulates. Makes me laugh when people call EV's zero emission vehicles...

Just a couple sources/references shown below.

https://www3.epa.gov/ttnchie1/confer...9/dbeltran.pdf

The contribution of non-exhaust road traffic emissions to the total PM10 emissions can be as high as 90% in northern European countries.

http://ec.europa.eu/transport/roadsa...culates_d8.pdf

For example, it has been
reported that tyre wear is responsible for the
release of around 40,000 tonnes of polycyclic aromatic
hydrocarbons (PAH), in the form of respirable PM,
across Europe each year (New Scientist, 1999). Miguel
et
al.
(1999) found that paved road dust contains at
least 20 source materials known to cause or exacerbate
allergic reactions in humans, including pollen, anim
al dander and fungal spores.
Paved road dust becomes
resuspended in the atmosphere in the wake of vehicl
es, thus increasing allergen concentration levels above
those that would prevail without the traffic movement. The study showed that between 0.5% and 12% of the
allergenicity of airborne particles was attributable
to paved road dust emissi
ons. Similar findings were
obtained by Chow
et al.
(1994).

2.2 Tyre wear particles
In 1999 more than 54 million passenger car tyres were used
in the UK, equating to a total weight of more than
430,000 tonnes (Used Tyre Working Group, 2000). A new ty
re on an average European passenger car weighs
around 8kg, and loses roughly 1-1.5kg in
weight during its service lifetime, which is typically around 3 years
or 50-60,000 km. Thus, between around 10% and 20% of
the rubber which goes into a tyre will disappear
before the tyre is ready to scrap (Environment Agency
, 1998). Similarly, Ahlbom
and Duus (1994) arrived at
an average rubber loss figure for Swedish roads of 17%
. Based on the upper estimate for rubber loss of 20%,
around 90,000 tonnes of tyre material was lost to th
e UK environment from passenger cars alone during 1999,
mainly as a result of in-service wear.

2.3 Brake Wear particles
During forced deceleration, vehicle brake linings are s
ubject to large frictional heat generation and associated
wear. This mechanically-induced wear generates brake lin
ing particles which are subsequently released to the
environment. A Swedish study found that around 934 t
onnes of brake linings were used in 1993 (Malmo
E
n
vironmental Health Administration, 1998). Westerlund
(2001) calculated that, in Stockholm, passenger
cars, goods vehicles and buses released around 45 tonnes, 7.
6 tonnes, and 3.3 tonnes of brake lining material
to the environment each year, respectively. The
UK National Atmospheric Emi
ssions Inventory (Goodwin
et
al.
, 2002) indicates that in 2000 brake wear was responsible for 4,200 tonnes of PM
10
emissions in the UK

[kwaked]

Originally Posted by rbreding

Just so I make sure I understand you right. Our diesels know when they have left the city and initiate a regen when in rural areas?

Not exactly

There are certain criteria that needs to be met for a regen to occur

Engine temp, road speed, road speed for a certain length of time etc etc

This doesn't guarantee that you're not in a city but in most scenarios it does mean you will be out on open fast flowing roads, which is usually away from high population densities.


It's far from perfect, but after reading various sides from many articles over the years i'm convinced it's better than nothing, especially if you live within 100m of a main road

[kwaked]

Originally Posted by TDIwyse

People get very hung up on "tail pipe" emissions, but that's no longer the major source of PM10 or other particulates. Makes me laugh when people call EV's zero emission vehicles...

Completely agree that it's a massively complicated issue

Way i look at it is, as i need a car for my work, i can't do anything about road erosion, tyre wear, brake wear

Sure a 335d will make more of a environmental impact than say a Smart, but i'm a petrolhead so there are compromises i'm willing to make

From my research i'm 100% convinced that DPF's help massively in reducing PM10 health related problems

Even if i was taking a power/performance cost hit, i've seen enough research and spoke to enough lung and heart doctors to convince me i'd still run them

As it is, they're extremely reliable, they have no noticeable effect (road driving) on performance, so for us drivers that prefer something more performance oriented (which we must otherwise we'd be on the 318d forum) there are a fair few positives with no real negatives

Of course if we all cared THAT much about the environment and other peoples health we'd just walk everywhere

[TDIwyse]

Originally Posted by kwaked

Completely agree that it's a massively complicated issue...

Agreed.

Here's another good read.

http://www.durhamenvironmentwatch.or...enceFinal1.pdf

Standards and monitoring are now being introduced for PM
2.5 particles – termed ‘fine particles’ and mostly 1,000 to 2,500nm in
size – but there is nothing yet to cover the much smaller ones. The current standards are in terms of total mass, yet UFPs are generally around only one percent of the total mass but present the majority of the surface area that is reactive to human tissues. If the mass of a single inhaled 2.5 μm particle is divided into typical nanoparticles ~80nm, they would have 1000 times more surface area. For that reason alone, the mass-based PM standards are far from appropriate for UFPs.

...

Whilst US researchers switched to correlating PM 2.5 with health indicators authorities in Europe have tended to remained entrenched with the concept of PM10. There is, however, no longer and serious doubt that the size of the particles is the most important issue from a public health viewpoint and the reasons are obvious when the respiration of particles is considered in more detail.
•Particles larger than 10 μm (10 millionths of a metre) generally get caught in the nose and throat, never entering the lungs.
•Particles smaller than 10 μm (PM10) can get into the large upper branches just below the throat where they are caught and removed (by coughing and spitting or by swallowing).
•Particles smaller than 5 μm (PM5) can get into the bronchial tubes, at the top of the lungs.Only particles smaller than 2.5μm (PM2.5) in diameter can get down to the deepest (alveolar) portions of the lungs where gas exchange occurs between the air and the blood stream, oxygen moving in and carbon dioxide moving out [35].


I've got some references that show how the DPF are very efficient at moving the larger particles to the more dangerous smaller ultra fine and nano particle size. I am personally not convinced DPF's are an overall good thing...

[kwaked]

Interesting article

I'm happy to accept that PM2.5 cause as much if not more health problems than PM10


For me it doesn't change my view on DPF's though

1/ They remove 92% of PM2.5 and 95% of PM10

Not perfect by a long shot, but it still means that every diesel running a DPF is dramatically reducing particles that are causing major health problems for lots of people.


2/ Diesels pump out a significant amount of PM10, without a DPF this PM10 will be pumped out in high population areas at a level that is right in the golden zone to cause major health problems.


3/ Even without a DPF our cars pump out a fair bit of PM2.5 anyway

Even worse for those of us that live in cities, it's been shown to emit more PM2.5 under low load conditions i.e. tickover or shuffling between traffic lights
https://www.iitk.ac.in/erl/Index_fil...Manuscript.pdf


As i say they're not perfect by a long shot, but we have a pretty good solution for dramatically reducing some of the most harmful emissions our cars produce.

This for no negatives

Seems like a great compromise to me.


If i had to breath in emissions (which i do as i live in a large city), then the more people that run DPF's on diesels the better as far as i'm concerned.

There is no doubt that they remove a significant amount of PM be that PM10 or PM2.5

Even though i class myself as a petrolhead and have cars and bikes that are from the pre-cat period, if the laws and insurance companies allowed it, i still would run my DPF

To me there is not one single negative

[TDIwyse]

Originally Posted by kwaked

Interesting article

I'm happy to accept that PM2.5 cause as much if not more health problems than PM10


For me it doesn't change my view on DPF's though

1/ They remove 92% of PM2.5 and 95% of PM10
...

Well, it's the smallest particles that are most concerning... especially the UFP and nanoparticles (ref from post 10) as they can bypass the normal protection methods, get into the bloodstream and have high bioactive characteristics.

DPF's, in the process of reducing the mass of particles, they create even smaller and dangerous particles. From the previous link, even though mass is reduced, the reactive surface area of smaller particles increases as particle size and total mass goes down, and can even pass the blood/brain barrier.

Here's an example of lab testing of a DPF vs non DPV equiped diesel car. Slide 4 shows a very interesting graph showing how the DPF equiped car shifts emissions of particle size down into the nanoparticle area (<100nm), which is very concerning.

http://www1.eere.energy.gov/vehicles...er09_dwyer.pdf

[Chappers 71]

Originally Posted by kwaked

Completely agree that it's a massively complicated issue

Way i look at it is, as i need a car for my work, i can't do anything about road erosion, tyre wear, brake wear

Sure a 335d will make more of a environmental impact than say a Smart, but i'm a petrolhead so there are compromises i'm willing to make

From my research i'm 100% convinced that DPF's help massively in reducing PM10 health related problems

Even if i was taking a power/performance cost hit, i've seen enough research and spoke to enough lung and heart doctors to convince me i'd still run them

As it is, they're extremely reliable, they have no noticeable effect (road driving) on performance, so for us drivers that prefer something more performance oriented (which we must otherwise we'd be on the 318d forum) there are a fair few positives with no real negatives

Of course if we all cared THAT much about the environment and other peoples health we'd just walk everywhere

If indeed you were a true petrol head you wouldn't be driving a diesel

[TDIwyse]

Originally Posted by Chappers 71

If indeed you were a true petrol head you wouldn't be driving a diesel

And speaking of petrol engines ... the direct injected gas engines are horrible from a particle count perspective. And their particle size is right in that horrible <80nm range.

[kwaked]

Originally Posted by Chappers 71

If indeed you were a true petrol head you wouldn't be driving a diesel

I know, i know

I've got my "toys" that are all petrol, i hung on to a petrol daily for as long as i could, but with the mileage i do and the towing duties needed a diesel was going to happen eventually.


Mind you, saying that i still have a shite eating grin from the torque when i have a play

My previous daily was a 3.2L V6 A3 (petrol)
Great noise but only 350km per tank (90 euros) drove me crazy i was filling up twice a day some days

Amazing noise, but completely sterile handling

The 335d is a step up handling wise, but i do miss that noise.......

A mate owns a custom exhaust company, couple of times a year i miss the noise THAT much i seriously think about losing the back boxes and getting a full custom system fitted (i'd keep the DPF ), but all the 335d's with custom exhausts sound like bloody buses so it's put me off.

I'm happy with the 335d, no plans on changing it for the foreseeable future, eye still wanders on M2's though.................

[kwaked]

Originally Posted by TDIwyse

Well, it's the smallest particles that are most concerning... especially the UFP and nanoparticles (ref from post 10) as they can bypass the normal protection methods, get into the bloodstream and have high bioactive characteristics.

DPF's, in the process of reducing the mass of particles, they create even smaller and dangerous particles. From the previous link, even though mass is reduced, the reactive surface area of smaller particles increases as particle size and total mass goes down, and can even pass the blood/brain barrier.

Here's an example of lab testing of a DPF vs non DPV equiped diesel car. Slide 4 shows a very interesting graph showing how the DPF equiped car shifts emissions of particle size down into the nanoparticle area (<100nm), which is very concerning.

http://www1.eere.energy.gov/vehicles...er09_dwyer.pdf

Aye but you're looking at the grand canyon through a smarties tube though.

I understand your point that DPF's create smaller particles, i will accept that

The big thing missing from the picture is

1/ 95% of all other PM10 and PM2.5 particle are removed by the DPF

2/ Those particles that do come out, now come out in areas far less harmful to other people


Running a diesel engine is a dirty act, running any internal combustion engine is for that matter.

Sure DPF's don't solve that problem, i'll accept that they may cause other problems.
Compared to the problems caused when not running a DPF the "other" problems are insignificant though.

Imagine if every diesel car, truck, bus on the road removed their DPF's, we would all be screwed.
Inner cities and towns would be no go areas most of the year, the "old smoke" would earn it's name again, diesels would gradually be banned, there would be soooooooo many pollution restrictions put on cars that there would be no point driving anything more than a dandelion eating Smart.

As it is DPF's are a massive improvement on diesels without them, there emmisions and PM10/PM2.5 are dramatically reduced.

That to me is indisputable fact

Do they completely solve the PM10/PM2.5 problem = No
Is the a chance they produce smaller particles that are harmful = According to the sources you listed = yes

But it's already stopped 95% of PM10/PM2.5 before that, so the amount is insignificant compared to not running a DPF


What clinches it for me, is knowing that if i run without a DPF the people within 5m of my car have significant greater chances of health problems than running with one.
My family, loved ones and friends travel in my car, for me, to risk their health for absolutely zero gain, (monetary or real world performance wise) is monumentally selfish ignorant/stupid (delete as necessary).

The fact that it's also illegal, invalidates my insurance and will only be short term thing (stricter MOT's are coming, those running without a DPF will either have to sell their car at a significant price decrease or pay 1000euros+ to have one fitted again, this after they've paid what 350euros to have it removed).

For me it's a absolute no brainer

[TDIwyse]

Originally Posted by kwaked

...
The big thing missing from the picture is

1/ 95% of all other PM10 and PM2.5 particle are removed by the DPF

2/ Those particles that do come out, now come out in areas far less harmful to other people
...

1/ Are you sure it's not roughly 95% of the mass as opposed to 95% of the particles?


2 There is a growing area of study that calls that assertion into question. For example:

http://www.meca.org/resources/MECA_U...0713_Final.pdf

Once inhaled, UFPs are small enough to evade our respiratory defense mechanisms and lodge in the deepest recesses of our lungs. There, they are small enough to cross cellular walls and enter our bloodstream. Indeed, it is well known that inhaled UFPs differ from larger particles in their lung deposition patterns, in their clearance mechanisms, and in their potential to be transmitted from lungs to other tissues in the body.6
In addition to their health impacts, UFPs are also important because they represent the largest category of particulates from engine combustion. As shown in Figure 2, the greatest number of particles and the greatest amount of lung deposition occurs in the ultrafine particle size range.
...
Although precise apportionment of the health impacts of UFPs relative to total PM mass is not yet possible, a growing body of literature suggests that UFPs may be more toxic on a mass-equivalent basis than the elemental carbon that makes up much of engine PM mass emissions.For example, Sager and Castranova found that ultrafine black carbon particles were 65 times more inflammatory and cytotoxic, on a mass basis, than PM2.5-sized black carbon in the alveolar epithelial cells of rats.14

[rbreding]

Some of this stuff is over my head. Anyways are we concluding that a deleted diesel with a larger particulate is technically safer than a DPF diesel that has much finer particulate ?

[TDIwyse]

Originally Posted by rbreding

Some of this stuff is over my head. Anyways are we concluding that a deleted diesel with a larger particulate is technically safer than a DPF diesel that has much finer particulate ?

Well, we know all the particulates are "bad" (this includes tires, brakes, road surfaces, and tailpipe emissions). A concern is that by trying reduce the "mass" of particulates with various treatment techniques there might be unintended consequences that are also "bad".

Here's another great study comparing Euro 3 with and without DPF, versus the newer Euro 4 and 5 vehicles.

http://www.ft.dk/samling/20061/lovfo.../12/327149.pdf

The Euro 3 without DPF is about as good (and sometimes better) in much of the ultra fine and nanoparticle regions as the Euro 4/5 in many operating regions.

[robnitro]

Tdiwyse, thanks for those graphs.
It's because after euro3 they made a big deal about NOx. To drop NOx, you can't run lean, depend on egr to keep afr lower and run a lower compression ratio.

All of those NOx fighting techniques take away the ability of diesel to burn cleaner in a lean, high afr, high compression engine!

[kwaked]

Originally Posted by TDIwyse

1/ Are you sure it's not roughly 95% of the mass as opposed to 95% of the particles?


2 There is a growing area of study that calls that assertion into question. For example:

http://www.meca.org/resources/MECA_U...0713_Final.pdf

Once inhaled, UFPs are small enough to evade our respiratory defense mechanisms and lodge in the deepest recesses of our lungs. There, they are small enough to cross cellular walls and enter our bloodstream. Indeed, it is well known that inhaled UFPs differ from larger particles in their lung deposition patterns, in their clearance mechanisms, and in their potential to be transmitted from lungs to other tissues in the body.6
In addition to their health impacts, UFPs are also important because they represent the largest category of particulates from engine combustion. As shown in Figure 2, the greatest number of particles and the greatest amount of lung deposition occurs in the ultrafine particle size range.
...
Although precise apportionment of the health impacts of UFPs relative to total PM mass is not yet possible, a growing body of literature suggests that UFPs may be more toxic on a mass-equivalent basis than the elemental carbon that makes up much of engine PM mass emissions.For example, Sager and Castranova found that ultrafine black carbon particles were 65 times more inflammatory and cytotoxic, on a mass basis, than PM2.5-sized black carbon in the alveolar epithelial cells of rats.14

Again though, you are missing the fundamental point
Even IF the DPF causes smaller particles, it's still blocked 92% of PM2.5 and 95% of PM10

The particles you are talking about are a tiny fraction of the 8% PM2.5 and 5% PM10

There is really no alternative

1/ Run without a DPF and belch out 100% PM2.5 and PM10

2/ Run a DPF and belch out 8% PM2.5 and 5% PM10

It's a no brainer

That's even before you consider the fact that with a DPF installed these emissions are belched out further away from high population centres and more importantly not directly at people like we would if we drove in a town or city without a DPF

As i say, PM2.5 is significantly higher at load engine loads.

So without a DPF you're pumping seriously harmful particles out at a higher rate (low load) within meters of you, your family (in the car) and every pedestrian and household close by.

Originally Posted by rbreding

Some of this stuff is over my head. Anyways are we concluding that a deleted diesel with a larger particulate is technically safer than a DPF diesel that has much finer particulate ?

No, not in any way shape or form

As i no matter the tiny amount of smaller particles a DPF creates, it still filters out 95% of the larger PM10 and 92% of the smaller PM2.5 particles

Plus it only belches these out is less built up areas further away from population centres

Without a DPF you are belching out 100% PM10, 100% PM2.5 and directly where it does the most harm to you, your friends and family in the car and other people close by

Read this morning new stricter DPF regulations are being bought in this year in the UK

Any modifications/removal to emissions related devices, this includes DPF'S and EGR's is now a major fail.

Where a DPF canister has clearly been cut open and re-welded, it will now fail.

A vehicle fitted with a DPF that emits any kind of visible smoke during the metered test will now fail

Emissions limits for diesels registered on or after 1st of January 2014 have been reduced. All diesels will now need to pass the limit that was set by the manufacturer when the car was new. This can be found on the VIN plate. For example the current limit for your diesel car may be 1.50. That could change to as low as 0.30 with the new rules.

Expect a LOT of really cheap diesels in the 2nd half of the year as the idiots that removed their DPF's panic

For sure there will be some stupid corrupt MOT testers that will still let cars through they know haven't got DPF's installed.


The new "visible smoke" test is the telling addition though

It will give cops the power to stop a car they believe is putting out too much smoke and demand a test

Last i heard it was a £1000 fine for running without a DPF on a 2009> car £2500 for a van

Be interesting to see how insurance companies react
If there is any chance of them skipping a payout then you can bet they will take it

Can't be long before they start checking

[TDIwyse]

Originally Posted by kwaked

Again though, you are missing the fundamental point
Even IF the DPF causes smaller particles, it's still blocked 92% of PM2.5 and 95% of PM10

The particles you are talking about are a tiny fraction of the 8% PM2.5 and 5% PM10

...

Actually, it seems like you're not reading/understanding the research papers and references I've been posting :-)

For example, you seem to be hung up on the health impacts of the larger particles which account for the vast majority of the mass, but the large particles aren't the ones getting into the bloodstream. Also, analysis of real world conditions show most of the mass of particulate emissions do not come from tailpipes (even in places with a majority of pre DPF equipped diesels).
The large particles can cause irritation in throat and upper lungs, but can be removed by natural protective mechanisms in our bodies. But they are too large to get into the bloodstream. This is where the ultra fine and nano particles are much more dangerous than the larger range of particles (see the deposition graph above and below reference and the data showing 6500% more toxicity in mamal studies). The real world behaviors of newer DPF equipped vehicles remove a lot of the larger particles, but are not doing a good job at removing the more dangerous smaller particles, and can actually shift and increase production of the smaller particles as they process the larger less dangerous ones ...

http://www.durhamenvironmentwatch.or...enceFinal1.pdf

In common with many leading researchers in this developing field of nano-toxicology such as Donaldson’s [26] and Oberdörster’s [27] groups, I have long considered ultrafine particles to be the main contributor to its adverse effects. Though UFP is only a small fraction of PM10 , Seaton et al. in 1995 [28] hypothesised biochemical processes whereby it might be the cause of acute cardiovascular effects. The 1999 Royal Society conference “Ultrafine particles in the atmosphere” and proceedings, published in 2000, consolidated the new thinking.

...

There is, however,no longer any serious doubt that the size of the particles is the most important issue from a public health viewpoint and the reasons are obvious when the respiration of particles is considered in more detail.
•
Particles larger than 10 μm (10 millionths of a metre) generally get caught in the nose and throat, never entering the lungs.
•
Particles smaller than 10 μm (PM 10) can get into the large upper branches just below the throat where they are caught and re
moved (by coughing and spitting or by swallowing).
•
Particles smaller than 5 μm (PM5) can get into the bronchial tubes, at the top of the lungs.
Only particles smaller than 2.5μm (PM2.5) in diameter can get down to the deepest (alveolar) portions of the lungs where gas exchange occurs between the air and the blood stream, oxygen moving in and carbon dioxide moving out [35]

...

Removal of the smaller particles (<2.5 μm) deposited in the alveoli is difficult. If soluble in water, they pass directly into the blood stream within minutes. If insoluble, they are collected by scavenging cells called macrophages, which transport them to lymph nodes where they are retained for months or years (NRC, 1979). However, lung macrophage cells
seem to have difficulty in recognising the smaller UFPs (those <65 nm; Donaldson et al. 1999), so may let some of them through the lung epithelium, especially during episodes of high numbers. Once they penetrate the epithelium and enter the blood stream, UFPs may be transported around the body and potentially be absorbed into cells – a process called endocytosis. Gumbleton [36], and more recently, Yang [33] have reviewed nanoparticle mobility and removal mechanisms including endocytosis. UFPs can cross biological membranes, in common with many viruses, and their mobility within the body is thought to be high. 14

3.6
The mechanism of toxic action I have summarised and discussed a number of mechanisms by which UFPs can induce cell damage in my 2009 nanoparticle review for the WHO.