Alkyl nitrates and their contribution to reactive nitrogen at a rural site in Ontario

Abstract Alkyl nitrates (C 3 C 6 ), NO, NO 2 , HNO 3 and PAN were measured at a rural site in Ontario from 26 March to 27 April 1990. A series of nine alkyl nitrates were measured daily at this site. The sum of the concentrations of these alkyl nitrates ranged from 29 to 87 ppt. The alkyl nitrates were found to contribute, on average, only 1.8% of the sum of the odd nitrogen species. In this paper, we discuss the observed distribution of the alkyl nitrates in light of the relative formation and removal processes. The observed concentration distribution is consistent with the relative formation rates calculated using the observed alkane concentrations, although it is somewhat skewed toward the lower molecular weight nitrates. The importance of the alkyl nitrates, relative to multifunctional organic nitrates that are produced from OH reaction with alkenes, is discussed.