Car and rail pollutants raise a child's risk have of developing asthma, U. S. researchers have concluded.

Their data indicated those children living near major highway or railroad intersections had higher diagnoses of asthma, researchers from the Mayo Clinic in Rochester, Minn., said.

Dr. Young Juhn says in a statement, "Children who lived in census tracts facing the intersection with major highways or railways had about 40 percent to 70 percent increased risk of developing childhood asthma. What this tells us is that clinicians need to be concerned about neighborhood environment beyond home environment to understand the individual asthma case."

It has been reported that Juhn and colleagues looked at 3,970 people born between 1976 and 1979 in Rochester, Minn. Of the 1,947 subjects living in census tracts that faced intersections, 6.4 percent developed asthma, while 4.5 percent of those living in census tracts not facing intersections developed asthma.

The Journal of Allergy and Clinical Immunology has published the study. (With Inputs from Agencies)