It has been shown by numerous studies in Europe and in the United States that some people are sensitive to mercury fillings as mercury is a neurotoxin. Studies have linked mercury vapor to bad health effects. Amalgam fillings emitted mercury vapor. Low level long term exposure to mercury vapor may be more harmful than short term acute exposure to concentrated levels of mercury vapor. The primary source of mercury in Americans is from dental fillings. A New Zealand study of more than 10,000 people mainly below the age of forty indicated a higher incidence of neurological disorders including MS among people with a greater number of mercury Amalgam fillings.
Some people had their mercury fillings replaced with composite material. DAMS published some information about the dangers of mercury Amalgam fillings and published a survey indicating people who had their mercury fillings replaced were glad they had the procedure done.