[Sources of mercury].

Mercury and its compounds arising from many sources, among which dental amalgams, are present everywhere, usually in low concentrations. Mercury is absorbed by inhalation, ingestion and skin from the air, diet and water. A large proportion of the population absorbs also mercury vapour and amalgam particles from amalgam restorations. Mercury may lead to allergic and may cause toxic reactions. Presumably due to the mass media and instigated by acupuncturists, an unknown number of patients ascribe a large diversity of complaints to their amalgam restorations. Many of the complaints do, however, not fit the symptoms of mercury poisoning. If the amalgam restorations underlie the complaints indeed, the material has to be banned. Moreover, for the Netherlands estimated 70-120 million restorations of amalgam should be replaced by fillings of another material. The question then is which material(s) must be used to perform such an almost impossible large and expensive task.