Instrumental neutron activation analysis (INAA) techniques for filterable river water and suspended particulate matter (SPM)
are described together with preconcentration techniques and simple radiochemical procedures to allow analyses when the trace
element concentrations are very low (e.g. for mercury) and also when the sodium and calcium concentrations are very high.
Detection limits are given for these methods and compared with those of other analytical techniques, including inductively
coupled plasma emission spectrometry. The precision of measurement is between 10–15% for most elements and the detection limits
are between 1 ng–1 μg.