Researchers from the UK have called into question a theory suggesting that a previously reported risk of leukemia among children born close to overhead power lines could be caused by an alteration to surrounding air pollution. In a study published today, 31 October, in the Journal of Radiological Protection (the official journal of The Society for Radiological Protection), the researchers have found little evidence to support the ‘corona-ion hypothesis’ which has been cited as a possible explanation for the excess of childhood leukemia cases close to high-voltage overhead power lines in the UK prior to the 1980s.