Estimated environmental Hg exposure in the town of Idrija still poses a potential risk to susceptible groups of inhabitants. Actual internal exposure reflects mainly exposure to Hg° from dental amalgam and, to a certain extent atmospheric Hg°. The internal doses of Hg received in the Idrija children and pregnant women did not decrease the bioavailability of Se. Changes in activity of antioxidative enzymes were not associated with exposure to Hg in the town of Idrija.