Measurement of gaseous and particulate nitrates in the atmosphere

Abstract

Gaseous and particulate nitrates are simultaneously sampled on a train consisting of a Millipore FHLP filter and a Toyo 51A filter impregnated with NaCl, extracted from the filters and colorimetrically determined. The interferences of NO2, of a mixture of NO2 and O3, of PAN and of organic nitrate were examined and found to be negligible in most of the measurements. The field study indicated that the inorganic gaseous nitrate concentration was significantly correlated with the oxidant level, whereas the concentration of particulate nitrate had no correlation with the oxidant level. © 1976.