The new study looked at the effects on 60 people with mild and moderate asthma of walking along the western end of busy Oxford Street in London, where only diesel-powered taxis and buses are permitted.
The researchers, from Imperial College London, the New Jersey School of Public Health, and other international institutions, found that both during and after a two hour walk along Oxford Street, the test volunteers experienced increased asthmatic symptoms, reduced lung capacity, and inflammation in the lungs. It took a few hours for these to return to their normal levels.
The researchers confirmed their results by comparing how the same people were affected by a two hour walk in the traffic-free, western part of London's Hyde Park. Here, the volunteers experienced some of the same problems but to a far lesser degree.
This is the first study to investigate in a real-life setting, outside of the laboratory, if traffic fumes make symptoms worse for people with asthma. Two thirds of people with asthma believe this to be the case, according to Asthma UK.
The researchers believe that diesel exhausts cause problems for people with asthma because of the particulates - minute particles of dust, dirt, soot and smoke - which they release into the air. Particulates come in different sizes but those of less than 2.5 microns, and the tiniest "ultra fine" ones, can interfere with the respiratory system, because they are so tiny that they can be inhaled deeply into the lungs. Ultra fine particles can also be absorbed in the blood, which may have damaging effects.
The researchers found a correlation between the level of diesel exhaust particulates at street level during the two walks and reductions in lung capacity and increases in lung inflammation in the volunteers.
Diesel engines emit lower concentrations of carbon monoxide and carbon dioxide than petrol engines, but they can generate over 100 times more particles per distance travelled than similar sized petrol engines, and are major contributors to particulate pollution in the atmosphere. Previous studies have shown that in urban environments, almost 90 per cent of traffic-generated particulate matter is from diesel exhausts.
Professor Fan Chung, from the National Heart and Lung Institute at Imperial College London and one of the authors of the study, said: "Our study illustrates the need to reduce pollution in order to protect people's health. For the first time we are able to measure exactly what's happening inside the lungs of people with asthma when they spend only a couple of hours strolling in a real-life polluted area. By observing the effect of pollutant diesel particles on the lung surfaces, we can confirm that such an exposure causes inflammation in the lungs of asthmatic people.
"Our study should not necessarily deter asthmatic people from venturing into Oxford Street, but different measures to reduce the levels of pollution, and to protect the lungs of asthmatic people from the effects of pollution, should be considered," added Professor Chung.
The researchers measured air quality in the study areas and found more than three times as many ultra fine particles on Oxford Street compared with Hyde Park (65,229 pt/cc vs 18,298 pt/cc). The researchers also found that Oxford Street had more than three times as much nitrogen dioxide in the air (80.8 vs 20.9 micrograms per cubic metre) and six times as much elemental carbon (12.4 vs 2.0 micrograms per cubic metre).
The researchers measured lung function; symptoms; exhaled nitric oxide and condensate from the breath; bronchial reactivity; sputum and blood. They took measurements before, during and after the volunteers' walks.
While the changes that were reported in their study were relatively modest, the researchers would now like to investigate the cumulative effects of exposure to these diesel fumes over time and to look at the effects of pollution on other conditions such as cardiovascular disease. They also want to look into whether the treatments currently available to combat asthma are able to reduce the effects of exposure to diesel exhausts on the lungs, for example by analysing if it is possible to reduce these effects by using an inhaler or tablets before going for a walk in a polluted area.
Professor Chung is a Principal Investigator in the MRC-Asthma UK Centre in Allergic Mechanisms of Asthma at Imperial College London and King's College London, which was set up in 2005 to tackle severe asthma caused by allergies. The study was supported by the Health Effects Institute in Boston.
WAKE-UP provides new treatment option for stroke patients | International study led by UKE
17.05.2018 | Universitätsklinikum Hamburg-Eppendorf
First form of therapy for childhood dementia CLN2 developed
25.04.2018 | Universitätsklinikum Hamburg-Eppendorf
So-called quantum many-body scars allow quantum systems to stay out of equilibrium much longer, explaining experiment | Study published in Nature Physics
Recently, researchers from Harvard and MIT succeeded in trapping a record 53 atoms and individually controlling their quantum state, realizing what is called a...
The historic first detection of gravitational waves from colliding black holes far outside our galaxy opened a new window to understanding the universe. A...
A team led by Austrian experimental physicist Rainer Blatt has succeeded in characterizing the quantum entanglement of two spatially separated atoms by observing their light emission. This fundamental demonstration could lead to the development of highly sensitive optical gradiometers for the precise measurement of the gravitational field or the earth's magnetic field.
The age of quantum technology has long been heralded. Decades of research into the quantum world have led to the development of methods that make it possible...
Cardiovascular tissue engineering aims to treat heart disease with prostheses that grow and regenerate. Now, researchers from the University of Zurich, the Technical University Eindhoven and the Charité Berlin have successfully implanted regenerative heart valves, designed with the aid of computer simulations, into sheep for the first time.
Producing living tissue or organs based on human cells is one of the main research fields in regenerative medicine. Tissue engineering, which involves growing...
A team of scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg investigated optically-induced superconductivity in the alkali-doped fulleride K3C60under high external pressures. This study allowed, on one hand, to uniquely assess the nature of the transient state as a superconducting phase. In addition, it unveiled the possibility to induce superconductivity in K3C60 at temperatures far above the -170 degrees Celsius hypothesized previously, and rather all the way to room temperature. The paper by Cantaluppi et al has been published in Nature Physics.
Unlike ordinary metals, superconductors have the unique capability of transporting electrical currents without any loss. Nowadays, their technological...
02.05.2018 | Event News
13.04.2018 | Event News
12.04.2018 | Event News
18.05.2018 | Power and Electrical Engineering
18.05.2018 | Information Technology
18.05.2018 | Information Technology