Studies on Environmental Pollution by Chemical Substances. II. Determination of Aromatic Nitro Compounds in River and Sea Water

Abstract

An analytical method for aromatic nitro compounds, such as nitrobenzene, o-, m-, and p-nitrotoluene, o-, m-, and p-nitroanisole, o-, and m-dinitrobenzene, and 2, 4, 2, 6-, and 3, 4-dinitrotoluene, in river and sea water is described. One liter of sample water was extracted with benzene in the presence of hydrochrolic acid. The extract was dehydrated and concentrated to 10 ml by a Kuderna-Danish (K. D.) evaporative concentrator. The extract was cleaned up by a Florisil column chromatography, and the components were eluted with benzene-ether (98 : 2, v/v). The eluate was concentrated to 10 ml and then quantified by a gas chromatograph (GC) with an electron capture detector (3H). A 5 ml portion of the solution was concentrated to 0.1 ml by the micro-K. D. evaporative concentrator and then qualified by a gas chromatograph-mass spectrometer (GC-MS) with a multiple ion detector. The recovery by this procedure was 86-99%, and as little as 0.025 to 0.25 ppb of the aromatic nitro compounds was able to be determined. The samples were obtained from the mouths of six rivers in Kanagawa Prefecture and the Tokyo Bay. Nitrobenzene was found in all of the samples and their content was 0.16-0.99 ppb. o-Nitroanisole (0.68 ppb) was detected in the water of the Tsurumi River in Yokohama City.