Biophysical assessment of single cell cytotoxicity

published 2012 May 25 Biophysical assessment of single cell cytotoxicity; diesel exhaust particle-treated human aortic endothelial cells.

Exposure to diesel exhaust particles (DEPs), a major source of traffic-related air pollution, has become a serious health concern due to its adverse influences on human health including cardiovascular and respiratory disorders. To elucidate the relationship between biophysical properties (cell topography, cytoskeleton organizations, and cell mechanics) and functions of endothelial cells exposed to DEPs, atomic force microscope (AFM) was applied to analyze the toxic effects of DEPs on a model cell line from human aortic endothelial cells (HAECs). Fluorescence microscopy and flow cytometry were also applied to further explore DEP-induced cytotoxicity in HAECs. Results revealed that DEPs could negatively impair cell viability and alter membrane nanostructures and cytoskeleton components in a dosage- and a time-dependent manner; and analyses suggested that DEPs-induced hyperpolarization in HAECs appeared in a time-dependent manner, implying DEP treatment would lead to vasodilation, which could be supported by down-regulation of cell biophysical properties (e.g., cell elasticity). These findings are consistent with the conclusion that DEP exposure triggers important biochemical and biophysical changes that would negatively impact the pathological development of cardiovascular diseases. For example, DEP intervention would be one cause of vasodilation, which will expand understanding of biophysical aspects associated with DEP cytotoxicity in HAECs.

PLoS One. 2012;7(5):e36885. Epub 2012 May 25. http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0036885

Controlled human exposures to diesel exhaust

Controlled human exposures to diesel exhaust

Published 31 May 2012

...

Many extra-pulmonary health effects of diesel exhaust exposure, including systemic inflammation, pro-thrombotic changes, and cardiovascular disease, are considered consequent to pro-inflammatory events and inflammation in the lung. Future research will focus on the relative importance of diesel exhaust components, potential interactions between components and other pollutants, effects in sensitive individuals, and effects of longer or repeated exposures.

Full Free text at Swiss Medical Weekly:

http://www.smw.ch/content/smw-2012-13597/

Inflammatory Effects of Diesel Exhaust Particles in Children and Adults

Inflammatory Effects of Diesel Exhaust Particles in Children and Adults / Lin / Sanchez



http://www.docstoc.com/docs/525918/Inflammatory-Effects-of-Diesel-Exhaust-Particles-in-Children-and-Adults

PS. This is one of our top-posts and one of the best presentations to understand the very severe health problems exposure to diesel exhaust induces.

The Toxicity of Diesel Exhaust Implications for Primary Care

Diesel fuel and the products of its combustion represent one of the toxins most commonly encountered by people living in both urban and rural areas of the world. As nations become more heavily populated, there will be increasing reliance on diesel fuel to power mass transportation and commercial vehicles, as well as heavy machinery involved in construction, farming, and mining. The majority of patients who present to urban primary care clinics and emergency departments will have had significant chronic exposure to diesel exhaust because most use and/or live near busy streets and highways. Furthermore, those who operate or work or live near diesel-powered machinery will have even more toxic exposure. Primary care physicians should be aware of the acute and chronic deleterious clinical effects of diesel exhaust. In this article we review the toxicity and myriad health problems associated with diesel exhaust.

http://www.jabfm.org/content/21/1/55.short

Effect of a diesel engine ban on asthma-related morbidity in Beirut

Recap: On July 1, 2002, a ban was imposed on the use of diesel-operated vehicles on the Lebanese territory as a public health measure.

Results: The average concentration of particulate matter was 181.3 g/m3 and 97.1g/m3 before and after the ban respectively. The total numbers of ER visits for pediatric patients were 6453 and 6865 in period 1 and period 2 respectively. Of those, 313 were due to asthma in period 1 and 223 in period 2. The number of asthma-related visits was significantly reduced during period 2. When we looked at the monthly distribution of visits, asthma-related visits were significantly reduced during October, November and December of period 2 compared to the same months of period 1, while it was significantly increased during the month of June.
Discussion: This study shows that a ban on diesel engine resulted in a decrease in the air concentration of particulate matter and was associated with a reduction in the number of emergency room visits for acute asthma. This reduction was most marked during the season of viral respiratory infections. We postulate that a reduction in the concentration of air pollutants was protective against viral-induced asthma exacerbations.

http://eprints.soton.ac.uk/52847/

More Recap on Diesel Ban

Oslo mulls winter ban on diesel cars

“(Diesel engines) are the big bad wolf when it comes to air quality,” he said.

The city experimented with closing its streets to diesel emissions in February 2011, when the last digits on licence plates determined whether a vehicle could enter the city on days when the air was “acutely bad”.

This year, a number of actions are being considered: making all diesel-driven cars stay away; a ban on all personal cars burning diesel; no driving alone in a diesel-powered car and no heavy transport through the city.

http://www.thelocal.no/page/view/diesel-cars-set-to-idle-in-winter

Madrid bans new taxis and buses running on diesel

lberto Ruiz-Gallardón, Mayor of Madrid has announced last week during an informative breakfast meeting in Madrid that the City Council of Madrid is preparing a regulation that will prevent the purchase of new taxis and urban buses running on diesel.

“The Transport Municipal Company (EMT) will not buy diesel vehicles and the taxis renovation will not be done with diesel vehicles anymore” declared Gallardón.

This decision was taken because diesel models emit too much NO2. Madrid is the first European city that acts against Diesel technology for environmental reasons. The municipality will not force to buy any special technology, but will establish a control not only in terms of CO2 but also regarding the NO2 emissions.

http://www.ngvaeurope.eu/madrid-will-ban-new-taxis-and-buses-running-on-diesel

Diesel exhaust particulate induces pulmonary and systemic inflammation in rats without impairing endothelial function ex vivo or in vivo

Diesel exhaust particulate induces pulmonary and systemic inflammation in rats without impairing endothelial function ex vivo or in vivo

http://www.particleandfibretoxicology.com/content/9/1/9/

Asthma Rates Climb for Children, Adults

Some 24.6 million Americans had asthma in 2009, up from 20.3 million at the beginning of the decade, according to a new report from the Centers for Disease Control and Prevention.

Asthma, a chronic respiratory disease, affected 8.2% of all U.S. residents in 2009, up from 7.3% in 2001, an increase of 12.3%, the CDC said. Children were more prone than adults to have asthma, and women more than men. African-Americans were affected at higher rates than other ethnic groups. About half of persons with asthma reported having an asthma attack in the preceding 12 months, the CDC said.

http://online.wsj.com/article/SB10001424052748704740604576301342646270586.html

How the Auto Industry fought against the Diesel Ban in Greece

eagleAID an Automotive Industry Website sums up how the Automotive Industry has been directly involved in recklessly promoting hazardous diesel vehicles and even overturning sound diesel ban legislation...

While diesels have continued to make large inroads into Europe’s car market, including of late even Switzerland and Scandinavia’s small markets - all comparative latecomers to Europe’s diesel car sales party - there was just one single market that clearly bucked the trend.

That market was Greece, and the reasons are easily identified.

Greece, some 20 years ago, banned the use of diesel powered cars in its two biggest cities.

As a result, diesel-powered cars could not be driven in either Athens or Thessaloniki, which couldn’t fail but impact on the country’s diesel car market.

That’s chiefly because a large chunk of the cars sold in Greece in an average year are sold in those two metropolitan areas.

The ramifications were such that Greece stood out as the only European car market with a virtually static and low single-digit diesel car sales share...

http://www.eagleaid.com/AID-Newsletter-preorder-1208e-Diesel-latecomer.htm

More here as well:

http://www.grreporter.info/en/ban_diesel_cars_movement_athens_and_thessaloniki_cancelled/5432

Oslo may restrict driving with diesel

Norway’s government once urged Norwegians to buy cars that use diesel, thinking they were less polluting, but later determined that wasn’t true because of their nitrogen oxide emissions. Now Oslo’s city government is poised to ban driving with diesel on cold winter days, to reduce smog in the capital.

http://www.newsinenglish.no/2012/06/14/oslo-may-restrict-driving-with-diesel/
This is good news.
We hope the WHO Report on adverse health effects of Diesel Exhaust will have also an impact on policy and legislation in other countries.

But, Citizens and Politicians, beware of the Diesel / Big Oil-Lobby / Automotive Industry! They just recently achieved to cancel the Diesel Ban in Athens that was introduced in 1991.

New diesels produce similar nitrogen oxides to those bought 15 years ago. ..

Urban nitrogen dioxide is mainly from traffic. While exhaust catalysts have decreased total nitrogen oxides from petrol cars by around 96%, real-world tests show that pollution controls on diesel cars are not as effective. New diesels produce similar nitrogen oxides to those bought 15 years ago.

Typical modern diesel cars emit around 20 times more nitrogen oxides than petrol cars. Less traffic would be the most effective way to decrease air pollution but is difficult to achieve quickly. Electric cars require new charging points. Offering incentives for small petrol and petrol hybrid cars, as well as reversing the trend towards more diesel vehicles, could be a practical route to controlling urban nitrogen dioxide.

http://www.guardian.co.uk/environment/2012/jul/08/pollutionwatch-diesel-petrol-electric-cars



and for more details, lets have a look at this study from 2004:

This study concludes that the replacement of gasoline with modern diesel vehicles in the U.S. may drive up photochemical smog, including total column ozone, near surface ozone, and nitrogen-containing species, over the U.S. on average and in the Southeast in particular, unless NOx emissions and the NO2:NO ratio from diesel vehicles are reduced to or below those of gasoline vehicles. The study also finds that vehicle NOx controls may be more effective than NO2:NO ratio controls at reducing ozone.

http://www.stanford.edu/group/efmh/jacobson/Articles/I/DiesNOxTextnew.pdf

Respiratory Effects of Exposure to Diesel Exhaust

The effects were greater in subjects with moderate asthma than in those with mild asthma. These changes were accompanied by increases in biomarkers of neutrophilic inflammation (sputum myeloperoxidase, 4.24 ng per milliliter after expo- sure in Hyde Park vs. 24.5 ng per milliliter after exposure on Oxford Street; P=0.05) and airway acidification (maximum decrease in pH, 0.04% after exposure in Hyde Park and 1.9% after exposure on Oxford Street; P=0.003). The changes were associ- ated most consistently with exposures to ultrafine particles and elemental carbon. Conclusions Our observations serve as a demonstration and explanation of the epidemiologic evidence that associates the degree of traffic exposure with lung function in asthma.

from "The new england journal of medicine"

http://www.des-pneumo-idf.com/s/IMG/pdf/Respiratory_Effects_of_Exposure_to_Diesel.pdf

"Phasing out Diesel"

Before things get worse, we should apply our mind towards adopting the Delhi model for a Imphal with cleaner and healthy air. We could start by phasing out the diesel autos from the city within a limited timeframe.

http://kanglaonline.com/2012/06/ban-diesel-autos/

Cell Damaging Reactive Oxygen Species (ROS)

EPFRs can be environmentally persistent but also biologically active by generating cell damaging reactive oxygen species (ROS). These ROS induce oxidative stress, a defense mechanism in the body where the immune system “over-responds” to invaders. When this process is started by free radicals it becomes a contributor to heart and lung dysfunction as well as DNA damage. This works by the EPFR’s ability to “piggy-back” on particulate matter (PM) which is then inhaled and transferred to the alveolar region of the lungs. This site will easily transport particles to other tissues in the body because of its close relation to the blood stream and the high amount of blood flow.

http://www.srp.lsu.edu/files/item24088.pdf

Diesel Exhaust Prime Source for Persistent Free Radicals

The expression PFR, Peristant Free Radicals or EPFRs, Environmentally Persistent Free Radicals explained:

Environmentally Persistent Free Radicals (EPFRs) are formed in combustion and thermal processes including hazardous waste incineration and diesel combustion. These processes create tiny particles called Particulate Matter (PM). PM is classified as coarse (10-2.5 μm), fine (2.5-0.1 μm), and ultrafine (0.1 μm and smaller). (To put this size into perspective, a human hair is approximately 70 μm in diameter, so the largest fine particle is still 30 times smaller than that.) 90% of ultrafine particles are formed from combustion sources, and these particles have the potential to penetrate in to the deepest portion of the lungs (the alveolar region). These particles provide the perfect breeding ground for EPFR formation. The free radical first forms a “loose” bond with the surface of the particle. Next, the EPFR is formed when the loosely bonded free radical forms a chemical bond with metals present in the particle in order to stabilize its own unpaired electron. This process reduces the metal allowing the attached EPFR to have a half life of up to several days rather than the fractions of a second of a normal free radical. EPFRs are also present in some contaminated soils as well as in ambient air. A recent Baton Rouge air sample revealed that airborne fine PM contained EPFRs with concentrations of 1017- 1018 radicals/g of air.

http://www.srp.lsu.edu/files/item24088.pdf

Persistent Endothelial Dysfunction in Humans after Diesel Exhaust Inhalation

Persistent Endothelial Dysfunction in Humans after Diesel Exhaust Inhalation.


Rationale:
Exposure to combustion-derived air pollution is associated with an early (1–2 h) and sustained (24 h) rise in cardiovascular morbidity and mortality. We have previously demonstrated that inhalation of diesel exhaust causes an immediate (within 2 h) impairment of vascular and endothelial function in humans.

Objectives: To investigate the vascular and systemic effects of diesel exhaust in humans 24 hours after inhalation.
...

Conclusions:
Twenty-four hours after diesel exposure, there is a selective and persistent impairment of endothelium-dependent vasodilatation that occurs in the presence of mild systemic inflammation. These findings suggest that combustion-derived air pollution may have important systemic and adverse vascular effects for at least 24 hours after exposure. http://www.ncbi.nlm.nih.gov/pubmed/17446340

Urban Air Initiative?

A new promising but also questionable campaign called the "Urban Air Initiative" has been launched http://urbanairinitiative.com

We are looking forward to see how this campaign will develop.

There are some signs that the Diesel-Lobby is trying hard to 'white-wash' Diesel Exhaust with the help from Burson-Marsteller and bought "Scientists". One of the alleged Junk-Scientists, "Consultant" and Meteorologist is Loren Carl Marz, who already in 2002 suggested - against all scientific evidence - that Diesel was less harmful than petrol. More alleged Junk-Science is now produced and released by the American Geophysical Union including Roya Bahraini... unfortunately the urbanairinitiative.com has no problem with citing Bahraini as a credible source. Well maybe we must defend Baharaini a bit, the study focuses on Secondary Organic Aerosol Mass: from a Clean Air Perspective (as from where the urbanairinitiative.com claims to be looking things) this is just the wrong premise: From a toxicological point of view overall particulate mass isn't the relevant public health threat: On the alveolar level this means: the smaller and therefore lighter the particles the more dangerous. Thats why health experts today focus on Particle Numbers or even better on the LDSA (Lung Deposited Surface Area). Diesel Exhaust is far more toxic than gasoline exhaust and contains far more noxious nano-particles from which many are PFR's (Persitent Free Radicals).But Bahraini seriously concludes that only gasoline emission should be reduced, ignoring all relevant and recent science on diesel exhaust... Even from a climate change perspective Diesel is worse than gasoline (see Mark Jacobson et al., Stanford, Ca). The urban air initiative doesn't allow comments yet, but we d'like to discuss this issue with them.