Human bladder stones, surgically removed from a 4 years old boy, were studied by X-ray diffraction (XRD) and by electron microprobe analyses (EPMA). XRD data show that the bladder stones are mainly composed of struvite with minor apatite.

Tiny particles, <10 μm in size, composed of mercury (Hg) and selenium (Se) were found using scanning electron microscopy (SEM) and quantitative analysis by wave-length dispersive system (WDS). On the basis of their composition, the particles consist of tiemannite, a rare mineral with the ideal formula HgSe.

The young patient was not exposed to relevant mercury contamination and has no teeth fillings of amalgam. Although this observation is not conclusive, we suggest that Hg was introduced as methylmercury by food. The discovered tiemannite can be classified as endogenous mineral, i.e., directly precipitated from the same fluids that formed the host bladder stones. This assumption is supported by the fact that tiemannite and struvite can crystallize at the same temperature and pH values.

As proposed for the formation of tiemannite previously reported in the liver of cetaceans, we suggest that the tiemannite in the human body represents a probable product of demethylation of Hg. In this contribution, we suggest that Hg and Se were initially collected by urine in the human body and finally precipitated to form tiemannite under appropriate chemical-physical conditions together with the formation of the host bladder stone.

This observation suggests that the precipitation and accumulation of metals, including Hg and Se, in the human body can be considered a physiological response to eliminate part of these trace elements, thus enabling detoxification.

通过 X 射线衍射 (XRD) 和电子显微探针分析 (EPMA) 对从 4 岁男孩手术切除的人类膀胱结石进行了研究。XRD数据显示膀胱结石主要由鸟粪石和少量磷灰石组成。

使用扫描电子显微镜 (SEM) 和波长色散系统 (WDS) 的定量分析发现了由汞 (Hg) 和硒 (Se) 组成的小于 10 μm 的微小颗粒。根据其组成，这些颗粒由铁锰矿组成，这是一种具有理想分子式 HgSe 的稀有矿物。

这位年轻患者没有接触到相关的汞污染，也没有用汞合金填充牙齿。虽然这一观察结果不是决定性的，但我们认为汞是作为甲基汞通过食物引入的。发现的铁曼石可归类为内源性矿物，即直接从形成宿主膀胱结石的相同流体中沉淀出来。铁曼石和鸟粪石可以在相同的温度和 pH 值下结晶这一事实支持这一假设。

正如先前报道的在鲸类动物的肝脏中形成铁曼铁矿的建议一样，我们认为人体内的铁曼铁矿代表了 Hg 去甲基化的可能产物。在这个贡献中，我们建议 Hg 和 Se 最初是通过人体尿液收集的，最后在适当的化学物理条件下沉淀形成铁锰矿，同时形成宿主膀胱结石。

这一观察结果表明，包括汞和硒在内的金属在人体内的沉淀和积累可以被认为是消除部分这些微量元素的生理反应，从而实现解毒。