Living close to the pollution from a freeway or major road can have a serious impact on the development of a child's lungs, according to a study published in a prominent medical journal.

The new study, published in the British medical journal the Lancet, found a major reduction in the eight-year lung growth of children who lived within 500 metres of a major road or freeway, compared with those who lived at a distance of 1,500 metres or more.

While previous studies have shown the impact of regional air pollution in urban areas on respiratory effects such as increased rates of asthma, the study is the first to show local exposure to freeways is a separate and independent factor in lung growth.

W. James Gauderman of the University of Southern California and colleagues compared lung-function measurements of 3,677 children at 10 years old and again at age 18. The children were chosen from 12 southern California communities with a wide range of regional air qualities.

"In many urban areas, population growth is forcing the construction of housing tracts and schools near to busy roadways, with the result that many children live and attend school in close proximity to major sources of air pollution," the authors stated.

"In view of the magnitude of the reported effects and the importance of lung function as a determinant of adult morbidity and mortality, reduction of exposure to traffic-related air pollutants could lead to substantial public-health benefits."

The study is a followup by the research group to one published two years earlier in the New England Journal of Medicine that showed the negative impact of higher airborne or regional pollutants on children.