A method is described for the determination of trace metal ions, V, Al, Cu, Mo Zn, and U, in natural water samples by neutron
activation analysis, using organic coprecipitation as a preconcentration method. The preconcentration of trace elements was
accomplished by converting the dissolved trace metal ions into the oxine chelates atpH 5.2 and extraction of the chelates witho-phenylphenol which is a liquid above 56 °C and solidifies at room temperature. After cooling the extraction system, the fine
particles of the organic phase were collected on a millipore filter and the precipitate was air-dried in a clean environment.
The solid extract was wrapped up in a sheet of clean polyethylene and subjected to neutron irradiation in a reactor for less
than 10 min at a thermal flux of 2·1013 n·cm−2·sec−1. γ-Ray spectrometry by a coaxial Ge(Li) detector connected to a 1024-channel PHA was performed on the irradiated sample without
further chemical separation, and thus the ppb level concentration of the elements in natural water samples could be determined.
The fundamental study of the collection of the trace elements is also described.