It is demonstrated that NQO1 expression is the activation of aryl hydrocarbon receptor (AhR) pathway by propolis, which promotes lung repair in a mouse emphysema model caused by CS exposure (Barroso et al., 2017).Also, studies have proved that NQO1 P187S polymorphisms is determined as risk genotype in children with obstructive bronchitis, whose mother smoke actively during their pregnancies. This evidence concerns the gene AHR and pulmonary emphysema.