- Air pollution impairs the function of blood vessels in the lungs
- Air pollution is more harmful to lung circulation during exercise
- Obstructive sleep apnea patients are at greater risk
Air pollution is linked to increased pulmonary vascular tone which makes it more difficult for blood to flow to the lungs.
"This is the first human study to report an influence of air pollution on pulmonary vascular function," said lead author Dr Jean-Francois Argacha, a cardiologist at the University Hospital (UZ) Brussels, Belgium. "This is a major public health issue for people living in polluted urban areas where exercise could damage the lungs and potentially lead to decompensated heart failure."
‘Air pollution causes narrowing of the blood vessels in the lungs, this combined with the effects of pollution could cause decompensated heart failure.’
New research study conducted by a team of scientists revealed the effect of air pollution on pulmonary hemodynamics. The study assessed whether levels of outdoor air pollution influence echocardiography parameters. The parameters were used to evaluate the pulmonary circulation and right ventricular function.
The study participants were exposed to pollutants in a chamber with standardized conditions. The volunteers were exposed to ambient air or dilute diesel exhaust with a PM2.5 concentration for two hours in a randomized, crossover study design.
Echocardiography was conducted on the participants to check the effects of pulmonary vascular resistance at rest and during a cardiac stress test (dobutamine drug was given to stimulate heart function during physical activity).
A negative effect of PM10, PM2.5 and ozone was observed on pulmonary circulation on the same day and over five and ten days.
Higher amounts of air pollutants were associated with reduced pulmonary acceleration time and increased pulmonary acceleration slope.
Increases in PM10 and PM2.5 over 10 days time were linked to worse right ventricle function.
Negative impact of PM10 on pulmonary circulation was more pronounced in obstructive sleep apnea patients.
Exposure to diesel exhaust did not modify the pulmonary circulation compared to ambient air when the volunteers were at the resting stage.
Diesel exhaust exposure had an effect on the pulmonary circulation in the dobutamine administered group.
Dr Argacha said: "Our dual approach provides original data on the impact of air pollution on the pulmonary circulation. The individual study strengthens the plausible link emerging from the epidemiological research."
Regarding how to minimize the health risks, Dr Argacha said: "Our main advice is to limit physical activities during heavy air pollution.
More studies are needed before specific recommendations on intensity and duration of exercise can be given. Emission controls such as particulate filters have reduced tailpipe emissions, but other sources such as engine crankcases, tyres and brake wear are becoming important. No strong evidence exists on effectiveness of face masks to eliminate or reduce particle exposure."
He added that legislation protecting the population from air pollution is weak. He said: "Diesel emission control has been associated with health outcomes but unfortunately the standards defined by the European Union differ from those of the World Health Organization."
The individual study showed that exposure to diesel exhaust did not modify the pulmonary circulation compared to ambient air when the volunteers were resting but did when dobutamine was administered. "This suggests that pollution is more harmful to the lung circulation during exercise," said Dr Argacha.
Air Pollution Facts
Air pollution consists of particles (particulate matter [PM] of different sizes) and gases (nitrogen dioxide, ozone, etc).
Common sources of air pollution include household combustion devices, motor vehicles, industrial facilities and forest fires.
Annually 7 million premature deaths are linked to air pollution.
Five most polluted cities in the world
List of five most polluted cities in the world along with the primary pollutant information in each city
- China (coal)
- India (chromium)
- Russia (nickel)
- Peru (lead)
- Ukraine (radioactivity)
- Air Pollution - (
- Information on Air Pollution - (http://www.who.int/mediacentre/news/releases/2014/air-pollution/en/)
- Polluted Cities in the World - (http://www.conservationinstitute.org/10-most-polluted-cities-in-the-world/)