A new study published in the New England Journal of Medicine earlier this month found that long-term improvements in air quality are associated with positive effects on lung-function growth in children. The study took place in southern California, where air pollution levels have been on a downward trend over the past several decades due to the implementation of air quality control policies.
The lung function of 2120 children was measured in three separate calendar periods: 1994-1998, 1997-2001, and 2007-2011. Large improvements were found in the children studied from 2007-2011 as opposed to those children of the same age in the same communities from 1994-1998 and 1997-2001. The results were adjusted for age, gender, ethnicity, height, respiratory illness, and other variations and strong evidence was found that improved air quality improves lung-function growth.
“We saw pretty substantial improvements in lung function development in our most recent cohort of children,” said lead author W. James Gauderman, professor of preventive medicine at the Keck School of Medicine of USC.
Combined exposure of nitrogen dioxide and particulate matter fell approximately 40% over the course of the study. Lung growth improved more than 10% and the percentage of children with abnormally low lung function dropped from 8% in 1994-1998 to just 3.6% in 2007-2011.
“It certainly supports the efforts that have been made over 40 years to improve air quality,” Gauderman told Reuters Health. “We would expect improvements in other urban centers to produce similar improvements in children’s health.”
The results of this study provide more incentive to continue strengthening air quality policies, like the final version of the Clean Power Plan expected to be released later this year which would reduce air pollution and greenhouse gas emissions from power plants.
“These gains really aren’t fixed,” said senior report author Frank Gilliland, the Hastings Professor of preventive medicine at the Keck School of Medicine. “We have to maintain the same sort of level of effort to keep the levels of air pollution down. Just because we’ve succeeded now doesn’t mean that without continued effort we’re going to succeed in the future.”