Clearing the Air Indoor Air Exposures and Asthma Development
		Biological Agents § Sufficient evidence of a causal relationship §     House dust mite § Sufficient evidence of an association §     None found § Limited or suggestive evidence of an association §      Cockroach (in        preschool-aged        children) §      Respiratory syncytial        virus (RSV)
				Chemical Agents § Sufficient evidence of a causal relationship § None found § Sufficient evidence of an association § Environmental tobacco smoke (in preschool- aged children) § Limited or suggestive evidence of an association §    None found