Metals in Human Gall, Bladder, and Kidney Stones Based on an Electron Microprobe Investigation

Several particles of copper accompanied by a few particles of nickel, lead, and a compound composed of selenium containing minor Ni, Si, Cu, and Co were found in human gall, kidney, and bladder stones. The investigated particles occur as tiny grains, <10 µm in size, that are irregularly dispersed in the stones. Therefore, they were studied by scanning electron microscopy and qualitatively analyzed by energy dispersive system. One grain of copper contained a small amount of Ni and Zn, and some grains of nickel proved to contain Cr as trace element. Most of the discovered metals formed a single-phase grain. However, a few grains found in two gallstones were associated with inclusions of calcium and apatite. Based on the results presented in this contribution, we argue that most of the studied metals can be classified as endogenous particles, i.e., directly precipitated from the same fluids that formed their host human stones. This observation suggests that the precipitation and accumulation of metals in some human stones can be considered an efficient way to eliminate them from the human body.