Radon in water : a new environmental issue?

Interest in radon has burgeoned over the last decade following the realisation that its concentration in indoor air may reach significant levels under certain circumstances. Suddenly a new, albeit natural and long-standing, ''environmental hazard'' seems to have appeared in our midst, and its measurement and control have become important issues in some areas. A recent move by the United States Environmental Protection Agency to drastically lower limits for radon concentrations in drinking water has focused the attention of water supply authorities throughout the US on the issue, and raised concerns about the costs and even the practicability of compliance. This article attempts to put the radon issue into perspective for the New Zealand situation. (author). 18 refs