RETN and childhood onset asthma: Results herein also support the importance of Naphthalene, 4H-cyclobenta[def]phenanthrene, 1,2-benzanthracene, Chrysene and Benzo(e)acephenanthrylene in childhood asthma and clearly indicate that the plasma concentration of these compounds correlate with asthma related biomarkers including IgE, resistin, GMCSF, IFN-γ, IL-4, IL-5, IL-8 and IL-10.