Determination of major, minor and trace elements in urinary stones by neutron activation analysis.

In five kinds of human urinary stones 18 elements have been identified by instrumental neutron activation analysis (INAA). From the results it may be concluded that calcium is the most important initiating cation, magnesium is the second most significant one, and Na, Cl, Sr, Zn, Fe, Br and Co may also play an important role in the stone formation. The results indicate also that ions like Ca, Br and Cu are easily incorporated into the nucleus to form a urate stone; Mg and Sr, into the nucleus to form a magnesium ammonium phosphate stone; and Zn, into the nucleus to form a calcium oxalate combined with apatite stone. The differences in elemental composition among the different kinds of stones as well as across the layers of stones are statistically evaluated.