Amalgam and Mercury in the Dental Setting and the Efficiency of Amalgam Separators

Mercury is the only metal that is in liquid form at room temperature and it has over the years been used in various combinations to extract gold, in measuring devices, medicaments, paper industry, batteries and fluorescent lights as well as in dentistry as dental amalgam. Dental amalgam is a mixture of 50 % mercury and 50% of an alloy consisting of silver, tin, copper and zink particles and has been used in dentistry for many years. The environmental effect of mercury release into the sewer from dental practices and clinics, and the inability of the wastewater treatment plants to remove it from the sludge lead to the introduction of amalgam separators in Sweden in 1980. The ISO standard 11143 regulates the efficacy of the amalgam separators, which should be at a 95% level, but is based on a laboratory test rather than a clinical evaluation. This study looks at the available amalgam separators in use in four areas of Sweden, Uppsala, Stockholm, Östergötland and Skåne and compares their clinical efficiency. The clinical efficiency ranged between 75 to 95%, with most units below the 90% mark. In Östergötland a new improved separator is being tried, the Capere unit, which is based on finely ground pine bark treated with a chelator sensitive to all metals and used in conjunction with a cotton filter and a regular amalgam separator. This was shown to be superior to the other separators, with a 99, 9% removal of even the smallest amalgam particles and ionic mercury from the wastewater before leaving the clinic. Otherwise, combining more than one amalgam separator of the brands available on the Swedish market did not improve the efficiency of them