contexts: The oligodynamic effect ( from Greek oligos `` few '' , and dynamis `` force '' ) is a biocidal effect of metals , especially heavy metals , that occurs even in low concentrations . The effect was discovered by Karl Wilhelm von Nägeli , although he did not identify the cause . Brass doorknobs and silverware both exhibit this effect to an extent .
name: Oligodynamic effect
answers.input_text: short
answers.span_text: a biocidal effect of metals , especially heavy metals , that occurs even in low concentrations
questions.input_text: the oligodynamic effect is a phenomenon that describes