HOT article: nitrate radical real culprit in respiratory diseases?

24 Mar 2011

Although the presence of ozone and NO_x gases (i.e. NO^. and NO₂^.) are often linked to an increase in respiratory conditions such as asthma, the mechanism by which these pollutants cause respiratory distress is still not clear. Interestingly, the highly reactive NO₃^. (formed in the atmosphere at night by reaction of O₃ and NO₂^.) has been somewhat overlooked as a possible respiratory irritant despite numerous studies on its role in the atmosphere.

In this HOT paper Uta Wille and colleagues at the University of Melbourne follow up a previous study published in Chem. Comm. which identified the products of the reaction of the NO₃ radical with amino acids. Now, they have simulated the exposure of proteins present at the surface of the respiratory tract to a number of environmental pollutants, determining clear reaction pathways resulting in aromatic ring nitration of the amino acids studied. They note that nitrated aromatic amino acids are often observed in a wide range of inflammatory-immune responses such as asthma and cystic fibrosis, leading them to suggest that the NO₃ radical could actually be the real culprit in certain pollution-related diseases.