Two rooms over, the bachelor’s degree candidate Ilona Wagner is exploiting another selective behavior of superabsorbers. “Depending on the degree of cross-linking, superabsorbers also soak up water polluted with different metals at different rates,” she explains. She is experimenting with arsenic, cadmium, lead, and chromium—extremely toxic metals that are present in untreated industrial wastewater. Unfortunately, in underdeveloped countries and emerging markets they end up in the drinking water of millions of people. “There are processes for removing these toxins from the water, but they are complicated and very expensive,” says Wagner. Her initial experiments have shown that carcinogenic chromium salts, which are used in the tanning industry in India and Bangladesh, for example, can soon be removed from water by superabsorbers at rates as high as 99 percent. Because chromium salts are colorful, even laypeople can see this effect. In Wagner’s beakers, the superabsorber flocculates steadily, causing the greenish color of the chromium to disappear from the overlying water. Wagner’s idea is that even very small businesses could put fleeces containing superabsorbers, which are merely oversized diapers, into their tanning brew to remove the chromium and dispose of it separately. However, the road from her bachelor’s thesis to the implementation of her idea will be a long one.