The scientific community and public authorities need to thoroughly investigate the potential effects of the potential effects of the volcanic ash cloud originating in Iceland and now covering large areas of Europe (Nature 464, 1253; 2010).

Although the associated climate and meteorological phenomena are being well documented, questions arise as to what the environmental and public-health effects might be in the longer term. For example, micro- and nano-sized particles and residues could contaminate food, fields and water.

Samples can readily be obtained from the atmosphere, as well as from industrial and domestic filters in machinery. These need to be analysed for carbon and metallic particles, and the ash tested for radiation, because the volcano explosion arose from deep geological deposits that may contain radioisotopes. This research and monitoring could be undertaken by public-health departments.

It cannot be assumed that volcanic ash has no dangerous effects. It is the duty of public authorities to investigate and report back to the public.