The study, one of a handful to examine airborne pollutants near regional airports, suggests that officials should heed these overlooked emissions, posing potential health problems for locals.

The scientists measured a range of air pollutants near a general aviation airport for private planes and corporate jets in Southern California in the first half of 2008.

They found that emissions of so-called ultrafine particles, less than 1/500th width of a human hair, were significantly elevated when compared to background pollution levels.

Suzanne Paulson, atmospheric scientist at the University of California (UC), and colleagues noted that scientists have known that aircraft emissions during takeoffs and landings can seriously impact air quality near major airports.

However, researchers know little about the impact of such emissions at general aviation or regional airports, which tend to be located closer to residential neighbourhoods than major airports, the article notes.

Levels of these pollutants were up to 10 times higher at a downwind distance from the airport equal to about one football field and as much as 2.5 times higher at a distance equal to about six football fields, says an American Chemical Society (ACS) release.

The study appears online in ACS' Environmental Science & Technology.