Children's lung development in urban Los Angeles has markedly improved due to better air quality, according to a decades-long study released Wednesday.
While previous groups of kids tested were found to have stunted lung development and be at increased risk for asthma after living close to freeways, the lung development of the latest group was much closer to kids who live in clean air zones, according to the study from University of Southern California researchers, which was published in the March 5 issue of the New England Journal of Medicine.
The study details the two-decade long process of following more than 2,000 children in the same geographic locations. USC researchers say local, state and federal air quality regulations have helped clear the air, and they see the results in kids' lungs.
Professor Jim Gauderman and his team at USC studied cohorts of kids over the last 20 years, making them breathe and blow to test the growth of their lungs.
Better lung development, means better life prospects, according to Gauderman. "As children transition into adulthood," he said, "if they’ve got better lung capacity it will set them up for lower risks of respiratory and heart disease later in their life and even to longer life span."
Researchers found that "children’s lungs grew faster as air quality improved."
Yet study authors warned against complacency. "Our population is continually increasing, meaning more cars on our roads, and economic activity will also grow leading to more ships in the ports, more trains and trucks on our roads as well," Gauderman said.
The ongoing California drought is expected to raise pollution levels, too.
"So if no new control technologies are introduced, we're likely to see air quality get worse in future years," Gauderman added. "It's important to continue developing those new strategies so that the impressive gains that have occurred in the previous decades are not lost in the coming ones."
The South Coast Air Quality Management District, the agency responsible for monitoring air quality, welcomed the news. In a press statement, the agency's executive officer, Barry Wallerstein said: “This study shows that our efforts to clean the air are paying dividends for children’s health today as well as throughout their lifetimes.”
The statement pointed out that while levels of ozone and fine particulates had decreased in Los Angeles, "much more remains to be done to meet current federally mandated standards for those pollutants."
This story has been updated.