Air pollution has been linked to an increased risk of cardiovascular disease, respiratory problems, lowered life expectancy, and overall reduced health and wellbeing.Life expectancy can be impacted by exposure to fine particulate matter
But in a new study, researchers from Imperial College London and Carnegie Mellon University have discovered that mortality and life expectancy are affected by exposure to fine particulate matter called PM2.5.
PM2.5 can be emitted from cars and power plants and are so small they can be easily breathed in. Accumulations of these particulates in the lungs can increase the risk of many heart and lung diseases.
In this study, the researchers analyzed PM2.5 concentrations in the United States from 1999 to 2015. All counties in the US except Hawaii and Alaska were included in the study.
Data from 750 air quality monitoring stations in the US, along with satellite images, were reviewed for the study.
The highest PM2.5 levels during the years analyzed were recorded at 22 micrograms per cubic meter of air in Fresno County, California, in 1999.
Even though PM2.5 concentrations have decreased since 1999, the researchers discovered that levels below current standards increase the risk of disease.
Currently, the yearly standard for PM2.6 concentrations is 12 micrograms per cubic meter of air, and in 2015, the highest concentrations were 13.2 micrograms in Tulare County, California.
The researchers combined the PM2.5 data with mortality data from the National Center for Health Statistics.
Between 1999 and 2015, there were 41.9 million deaths in the US, and 18.4 million were attributed to cardiovascular disease.
A statistical model was used to predict the increased risk of death per one microgram per cubic meter of air of PM2.5
The researchers estimate that PM2.5 levels between 2.8 and 13.2 micrograms in counties across the country can be linked to 15,612 deaths in females and 14,757 deaths in men from 1999 to 2015.
What the model projections show is that PM2.5 levels, even at low concentrations, decrease life expectancy in the US and increase mortality rates.
“We’ve known for some time that these particles can be deadly,” said Majid Ezzati, the lead author of the study. “This study suggests even at seemingly low concentrations – mostly below current limits – they still cause tens of thousands of deaths. Lowering the PM2.5 standard below the current level is likely to improve the health of the US nation, and reduce health inequality.”
The researchers published their findings in the journal PLOS Medicine.
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By Kay Vandette, Earth.com Staff Writer
Image Credit: Shutterstock/LanaElcova