Exposure to both traffic, indoor pollutants puts some kids at higher risk for asthma later

Exposure to both traffic, indoor pollutants puts some kids at higher risk for asthma later  
http://www.eurekalert.org/pub_releases/2009-11/uoca-etb111709.php
 
"New research presents strong evidence that the "synergistic" effect of early-life exposure to both outdoor traffic-related pollution and indoor endotoxin causes more harm to developing lungs than one or the other exposure alone."