Comment on 'A photoelectron spectroscopy study of lava stones' by D. A. Cristaldi, C. G. Fortuna and A. Gulino, Anal. Methods, 2013, 5, 3458

Exposure to high levels of manganese can cause neurotoxicity with the development of a form of parkinsonism known as manganism, a neurologic syndrome that resembles Parkinson's disease. A higher concentration of water soluble MnOOH species has been found at the surface of the lapilli emitted by the Etna volcano. Atmospheric agents can remove surface layers from the emitted stones that go directly into the air and groundwater of the surrounding area. This evidence correlates with the very high concentration of Mn recently reported in the groundwater collected from Etna wells. An excess of Mn in water has been connected to manganism disorders and, on this ground, a possible increased risk of developing manganism has been suggested in this area, even if to date this hypothesis has not been supported by epidemiological evidence.