Some air pollution 'is just as dangerous in the country as it is in city centres'

Air pollution may be just as dangerous in rural areas as it is in city centres, a new study has warned.

PM2.5 - tiny particles 2.5 microns or less in width - poses a health risk because it can become embedded in lung tissue when inhaled, the researchers warn.

The researchers said current methods of assessing PM2.5 pollution are lacking, as they focus on mass - and lighter particles are often more dangerous, according to Professor Vishal Verma of the University of Illinois Urbana-Champaign.

Verma said: "Most air pollution studies have shifted focus from particle mass to a property called cellular oxidative potential.

"Cellular oxidative potential describes the capability of the particles to generate reactive, oxygen-based chemicals that can lead to a variety of health problems in the cells of lung tissue."

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The researchers collected PM2.5 samples weekly in the summer and autumn of 2018 and in the winter and spring of 2019.

They chose three urban localities: Chicago, Indianapolis and St. Louis; a rural location in Bondville, Illinois; and a roadside location adjacent to an interstate highway in Champaign, Illinois.

The team found that all locations shared similar levels of oxidative potential - but the results suggested that some of the lighter particles that make up PM2.5 contribute more to tissue damage than others, the study reports.

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“The oxidative potential was equal to samples from urban settings," Verma said.

"Additionally, the oxidative potential of the rural samples was higher in the summer than in the winter, suggesting that summertime agricultural activity can produce PM2.5 particles that are just as toxic as those from urban settings."

The team hopes this study brings attention to these newly uncovered risks associated with PM2.5 in rural areas.

"The current methods used to measure PM2.5 oxidative potential are time-consuming and laborious, and we hope that our new methodology, combined with these study findings, makes testing for oxidative potential more appealing to environmental regulators and policymakers," Verma said.

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