Manganese to life and health. Generally, exposure to ambient Mn air concentrations in excess of 5 μg Mn/m3 can lead to Mn-induced symptoms. Increased ferroportin protein expression in human embryonic kidney (HEK293) cells is associated with decreased intracellular Mn concentration and attenuated cytotoxicity, characterized by the reversal of Mn-reduced glutamate uptake and diminished lactate dehydrogenase leakage. Waterborne manganese has a greater bioavailability than dietary manganese. According to results from a 2010 study, higher levels of exposure to manganese in drinking water are associated with increased intellectual impairment and reduced intelligence quotients in school-age children. It is hypothesized that long-term exposure due
Chemical clock can be added to some chemical clocks to build a chemical oscillator. For example, the Briggs-Rauscher reaction is derived from an iodine clock reaction by adding perchloric acid, malonic acid and manganese sulfate.. Chemical clock A chemical clock (or clock reaction) is a complex mixture of reacting chemical compounds in which the onset of an observable property occurs after a predictable induction time. In cases where one of the reagents has a visible color, crossing a concentration threshold can lead to an abrupt color change after a reproducible time lapse. One class of example is the iodine clock reactions, in