A study of 3600 children living near busy highways in southern California shows that auto emissions can stunt a child's lung development and increase the risk of early respiratory problems.  VOA's Melinda Smith has details about the research and what the findings hold for their future health.

Southern California has some of the worst traffic and air pollution in the United States.  That can be annoying for motorists stuck in their air-conditioned cars.  But Professor W. James Gauderman says it can be hazardous for children who live and play close to the highway.

"If you live both near a freeway and in an area of high air pollution, our results suggest that you're getting, in a sense, a doubling of the effect -- both the regional pollution levels that the children are breathing as well as the air that they are breathing, that is coming out of the tail pipe."

Professor Gauderman of the University of Southern California Medical School co-authored a study of children who live within 500 meters of a busy thoroughfare.  What he discovered was that lung capacity in these children was far weaker than in those kids who live at least 1500 meters away. That sets up a greater risk for childhood respiratory problems, like asthma.

One mother of two children who already have asthma says she is concerned about the pollution.

"It just seems that more and more are getting asthma nowadays than they did when I was a kid.  Nobody hardly had asthma, so I do think this is a problem."

Because lung development stops when children stop growing, the researchers were also concerned about their health as adults.  Respiratory problems in adulthood can lead to other illnesses, such as heart disease and emphysema.  Professor Gauderman says health and planning experts should take measures now to solve this looming problem.

"I think everybody should be alarmed about this, and I think the real message is probably to those that are planning land use and schools, and housing developments -- anywhere a child may be spending a lot of time near a busy road.  We think that the health effects should be taken into account."

Researchers also believe that state and local air-quality regulations will have to be adjusted to take into consideration how traffic patterns affect pollution. 

The study was over a 13-year period and was limited to 3600 children aged 10 to 18.