Air Pollution, Traffic Linked to Respiratory Deaths

Air Pollution, Traffic Linked to Respiratory DeathsAir Pollution, Traffic Linked to Respiratory Deaths

Researchers have shown for the first time that lung transplant patients in Europe who live on or near busy roads with high levels of air pollution are more likely to die or to experience chronic organ rejection, than those living in less polluted areas.

Dr David Ruttens, from the University of Leuven (Belgium) told the European Respiratory Society’s International Congress that the risk of dying increased by 10% for patients living in an area where air pollution was above World Health Organization (WHO) recommended maximum levels, compared with patients living in areas with lower levels of pollution.

However, this increased risk was not seen in lung transplant patients who were taking a class of antibiotics called macrolides, which include azithromycin and clarithromycin, reports Science Daily.

WHO estimates that 3.7 million people worldwide die prematurely every year as a result of exposure to small particulate matter measuring between 2.5-10 micrometers in diameter (known as PM10). Ten micrometers is less than the width of a human hair, and PM10 particles tend to be dust particles stirred up by vehicles on roads and some grinding operations. WHO recommends PM10 particles should not exceed 20 micrograms per cubic meter in the atmosphere.

Ruttens said: “Short and long-term exposure to air pollution has been linked to an increase in deaths from respiratory diseases, particularly among vulnerable populations. Lung transplant patients are among the most vulnerable because they have weakened immune systems due to the immunosuppressive drugs they have to take to prevent organ rejection.”

Around 50% of lung transplant patients survive for five years or more after their operation; a rate that is lower than for other organ transplants and is due to a higher incidence of chronic organ rejection. Doctors have suspected for some time that this might be due to air pollution.

Ruttens and a team of European researchers led by Prof. Bart Vanaudenaerde, also from the University of Leuven, collected data on 5,707 lung transplant patients from 13 major lung transplant centers in 10 European countries from 1987 to 2012, including follow-up data in 2013.

In order to standardize the information on road density and air pollution, researchers collaborated with an environmental expert consortium (ESCAPE) to quantify annual mean concentrations of PM10 particles and the distance from patients’ homes to the nearest main roads.

During an average of 5.6 years of follow-up, 2577 patients (45.2%) died and 2688 (47.1%) developed chronic organ rejection. A total of 3511 patients (62.2%) took macrolides at some point in their treatment, and 2149 patients (37.7%) did not.