Heavy exposure to black carbon is like smoking a pack a day for 15 years
Breathing in black carbon from diesel fumes, coal power plants, and forest fires increases the number of small blood vessels in the lungs, and exposure to high levels of black carbon causes the same amount of lung damage as smoking a pack of cigarettes a day for 15 years.
Researchers led by Columbia University professor Dr. Carrie Pistenmaa Aaron observed for the first time the impact that breathing in tiny black carbon particles has on the peripheral blood vessels in the lungs.
Even small amounts of particles could increase the risk of developing lung disease, which is the third leading cause of death worldwide.
The results of the study were published in the journal European Respiratory Journal.
“A few previous studies have suggested a link between air pollution and the pulmonary circulation, but we wanted to evaluate whether there were associations between chronic air pollution exposure and the vascular structure of the lungs,” said Aaron. “We were interested in the lung vasculature as we think it may be related to chronic lung conditions.”
For the study, the researchers reviewed data from the National Heart, Lung, and Blood Institute’s Multi-Ethnic Study of Atherosclerosis (MESA) Lung and Air Pollution Studies which included information from more than 3,000 people across six cities in the US.
The participants’ long-term exposure to outdoor air pollutants were recorded, and pulmonary blood vessels were measured with CT scans.
Important factors like age, height, sex, history of smoking, and medical history were included in the data.
The 3,000 participants were exposed to .8 micrograms of black carbon per cubic meter every year and 11 micrograms of fine particulate matter.
While these levels are well below air pollution limits set by the Environmental Protection Agency and the European Union, the researchers still found that black carbon exposure impacted blood vessels in the lungs.
“Our findings suggest that long-term exposure to black carbon may impact the pulmonary circulation,” said Aaron.
Because the study was based on cross-sectional observations, there are limits to the conclusions, but the researchers hope to further explore how black carbon impacts pulmonary blood vessels and lung disease risk.
“No previous research has looked specifically at whether these changes in humans lead to disease, so we cannot say for certain how this may be affecting health,” said Aaron. “However, other studies of similar pulmonary vascular measures on CT and MRI in humans, in addition to a number of studies in animals, suggest that differences in the pulmonary vasculature might make people more likely to develop chronic lung disease.”
Image Credit: Shutterstock/Igor Grochev