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That diesel exhaust we suck in when riding busy roads...


Chris NewbyFraser

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I was digging for facts to use in writing a safety procedure for some guys at work in our vehicle installation workshops. I found two articles about diesel exhaust which spooked me a bit and I am posting a short section of each, which provide the basic message for us cyclists who ride busy urban roads.

 

Diesel exhaust, a specific type of diesel fume, has more negative health effects than regular diesel fumes. Short-term exposure can irritate your eyes, nose, throat and lungs; it can cause coughs, bronchitis, headaches, lightheadedness and nausea.
Lengthy exposure to diesel exhaust may increase your risk of developing asthma, a variety of lung diseases, heart disease, as well as brain and immune system issues. In studies using human volunteers, exposure to diesel exhaust particles made people with allergies more susceptible to the materials to which they were allergic, like dust and pollen. Exposure may also trigger lung inflammation, aggravating chronic respiratory symptoms and increasing the frequency and severity of asthma attacks.
The 40 different toxic compounds found in diesel exhaust can cause immediate and serious health concerns.
A complex mixture of fine particles and gases, diesel exhaust contains both unburned diesel fuel and particulates (soot). The primary dangerous substances found in diesel exhaust include particulate matter, carbon monoxide, nitrogen oxides, hydrocarbons, volatile organic compounds, and other hazardous gases.
Diesel particulate matter (DPM), sometimes called diesel exhaust particles (DEP), is the term used for the solid or liquid particles the exhaust carries into the air. Some particles are visible as soot or smoke, but most are fine particulate matter, which is composed of very small objects floating in the air, like dust, dirt, soot, smoke, and liquid droplets. Ninety per cent of diesel particulate matter is considered fine particulate matter (less than 2.5 microns in diameter).
Diesel particulate also contains diesel soot and aerosols, including: ash particulates, metallic abrasion particles, silicates and sulfates. Since the fine particles are so small, you easily inhale them deeply into your lungs where they are quickly transported into your bloodstream. So, people with existing heart or lung disease, asthma or other respiratory problems are most sensitive to the health effects of these fine particles.
As well, the particulates' rough surfaces catch and carry other harmful, environmental toxins along with them as you breathe them deeply into your lungs. Inhaling this particulate matter may aggravate asthma, bronchitis, emphysema, and/or cause coughing and difficult or painful breathing, decreased lung function, weakening of the heart, heart attacks and/or premature death.
Carbon monoxide, another component of diesel exhaust, reduces your blood's ability to deliver oxygen to your organs, damaging these organs. Extremely high concentrations cause death. Nitrogen oxide, also found in diesel exhaust, covers a group of highly reactive gases composed of various amounts of nitrogen and oxygen.
Low levels of nitrogen oxide can irritate your eyes, throat, lungs and cause coughing, shortness of breath, tiredness and nausea. However, breathing high concentrations can trigger more serious symptoms like rapid burning, spasms and swelling of the throat and upper respiratory tract, reduced oxygen in your tissues and a build up of fluid in your lungs.
Nitrogen oxides damage lung tissue, lower your body's resistance to respiratory infections and can increase the severity of chronic lung diseases, such as asthma.
Since studies show that people who work around diesel equipment, including truck drivers, are more likely to develop these health issues than workers not exposed to diesel emissions, it is important to take precautions.

 

If the smell of diesel exhaust isn't enough to make you avoid getting a lungful, new research now shows that even a short exposure to the fumes can affect your brain. A study published in the open access journal Particle and Fibre Toxicology reveals that an hour of sniffing exhaust induces a stress response in the brain's activity.

Previous studies have already suggested that very small particles, called nanoparticles, breathed in from polluted air can end up in the brain. But this is the first time that scientists have demonstrated that inhalation actually alters brain activity.

Ten volunteers spent one hour in a room filled with either clean air or exhaust from a diesel engine. They were wired up to an electroencephalograph (EEG), a machine that records the electrical signals of the brain, and their brain waves were monitored during the exposure period and for one hour after they left the room.

The researchers found that after about 30 minutes the diesel exhaust began to affect brain activity. The EEG data suggested that the brain displayed a stress response, indicative of changed information processing in the brain cortex, which continued to increase even after the subjects had left the exposure chamber.

The concentration of diesel exhaust that the subjects breathed was set to the highest level that people might encounter in the environment or at work, for example on a busy road or in a garage.

Lead researcher Paul Borm from Zuyd University in The Netherlands said: "We believe our findings are due to an effect nanoparticles or 'soot' particles that are major component of diesel exhaust. These may penetrate to the brain and affect brain function. We can only speculate what these effects may mean for the chronic exposure to air pollution encountered in busy cities where the levels of such soot particles can be very high."

One link to understanding the mechanism of this effect is that oxidative stress is one consequence of particles depositing in tissue and oxidative stress has also been implicated in degenerative brain diseases such as Parkinson's and Alzheimer's disease . "It is conceivable that the long-term effects of exposure to traffic nanoparticles may interfere with normal brain function and information processing," noted Borm

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Very interesting. Wonder if it will offset the health benefits of commuting regularly.

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I wonder what type of diesel they refer to. 50 ppm burns much cleaner than 500ppm. I had a 30 year old truck with 700000 km on the clock. When I used 500ppm it smoked like a chimney, and with 50ppm there was hardly any smoke. Newer diesel engines now also have cats and burn even more cleaner.

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This is the cabin air filter from my wife's car, changed yesterday after about 1 year of low mileage driving in a busy neighborhood.

 

That black colour is some dust, but mostly carbon.

 

 

 

post-10549-0-52537800-1552025842_thumb.png

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Had a quick scan of the OP, will read with more intent later on, but I will say this: on days that I commute, I have noticed my HR being slightly higher at night when I am chilling at home, or am I just imagining things...

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Need remember, you breath this in while sitting in your car in the traffic, might even be more as you sit longer..  so cycling past still standing traffic I would guess is still more healthy

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.....

Ten volunteers spent one hour in a room filled with either clean air or exhaust from a diesel engine. They were wired up to an electroencephalograph (EEG), a machine that records the electrical signals of the brain, and their brain waves were monitored during the exposure period and for one hour after they left the room.

 

....

 

Who wants to do a test where we poison you? Maybe to even to death?!

 

Oo me me!

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I wonder what type of diesel they refer to. 50 ppm burns much cleaner than 500ppm. I had a 30 year old truck with 700000 km on the clock. When I used 500ppm it smoked like a chimney, and with 50ppm there was hardly any smoke. Newer diesel engines now also have cats and burn even more cleaner.

CATs/DPFs are not compulsory on diesel vehicles in ZA. We only comply to Euro2 emission standards. Our diesel tends not to comply with the required standards to run ‘cleaner’ diesel engines, so the models sold here often just run ’normal’ exhaust systems

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Who wants to do a test where we poison you? Maybe to even to death?!

 

Oo me me!

 

As soon as there is money / rewards available, people do silly things...

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Need remember, you breath this in while sitting in your car in the traffic, might even be more as you sit longer.. so cycling past still standing traffic I would guess is still more healthy

As posted by Lotus, most newer vehicles have HEPA filters

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This whole Diesel debate is quite interresting. Especially here in good old Germany where the heart of the Dieselgate scandal is.

 

We bought our 1.6 TDI Golf stationwagon (1 year old model) one month before the scandal broke news.  The debates and discussions since were endless.  We investigated the option of taking part in the class action agains VW but at the end decided that I don't think I will be a clear winner on the thing in anyway.  Best scenario is VW gives back my money (not all of it as usage of the car will be subtracted) and then I have to buy a new car again.  We are paying the last installments on the car in the next 3 or 4 months.

 

Now interresting the big cities in Germany are under pressure to get the carbon emmissions down below certain levels.  Now remember it is waaaay lower than SA cities in anyway but they still need to get it down.  One of the ways they are thinking of doing it is to block diesel cars from enterening the cbd areas.

 

Very recently studies came out and apart from the Nitro polution from the diesel engines, the carbon emmissions on diesel apparently are actually way lower than petrol.  So if everybody is going to swop their diesel cars for petrol, the cities have a snowballs chance in hell to achieve their targets.

 

Many of us are keeping our diesel cars and will wait for the hybrid and e-car markets and infrastructure to catch up.  I am quite happy with my diesel car that I owe nothing on and runs at a nice 5 liter/100 km combined cycle consumption (of did I mention we have autobahns here in Germany so very seldom driver under 150 on the highway).

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