Study reveals environmental impact of dental amalgam
SAN JUAN, Puerto Rico/SPRING, Texas, U.S.: Mercury in dental amalgam is a hidden source of global mercury pollution, resulting from factors such as the illegal diversion of dental mercury into the artisanal and small-scale gold mining industry, crematoria emissions from the deceased and sewage sludge that is sold to farmers. These significant mercury sources result in air, water and food contamination that consequently have a negative impact on human health. The aim of a recent study was to investigate and report on all of the various pathways of mercury in dental amalgam into the environment.
According to the United Nations Environment Programme, dental amalgam represents over 20% of the global mercury used in products. The Minamata Convention on Mercury is now in force, 110 countries of the 128 signatories having ratified the treaty. Countries are now working on implementation for treaty compliance.
Dental amalgam has been listed as a phase-down product in the Minamata Convention. The nine provisions are listed below:
(i) setting national objectives aiming at dental caries prevention and health promotion, thereby minimizing the need for dental restoration;
(ii) setting national objectives aiming at minimizing its use;
(iii) promoting the use of cost-effective and clinically effective mercury-free alternatives for dental restoration;
(iv) promoting research and development of quality mercury-free materials for dental restoration;
(v) encouraging representative professional organizations and dental schools to educate and train dental professionals and students on the use of mercury-free dental restoration alternatives and on promoting best management practices;
(vi) discouraging insurance policies and programs that favor dental amalgam use over mercury-free dental restoration;
(vii) encouraging insurance policies and programs that favor the use of quality alternatives to dental amalgam for dental restoration;
(viii) restricting the use of dental amalgam to its encapsulated form;
(ix) promoting the use of best environmental practices in dental facilities to reduce releases of mercury and mercury compounds to water and land.
The environmental impact that is caused by dental amalgam has been discussed within the text of the treaty, and factors such as sewage sludge, cremation, burial, human waste, and artisanal and small-scale mining are mentioned. However, there has been little research on the topic. According to the authors of the study, they believe that it is the first paper to address all of the pathways through which mercury from dental amalgam enters the environment as a cradle-to-grave deadly pollutant. They also stated that significant mercury pollution from cremation is growing owing to various factors. Cremation is less expensive than burial and is favored because of population density and lack of burial space. This increase in cremation is happening globally.
Another area of serious concern is sewage sludge. The European Federation of National Associations of Water Services advocated a ban on dental amalgam in order to decrease mercury in the sludge from wastewater treatment plants. They noted that the major source of the mercury in wastewater in most treatment plants in the EU is from dental amalgam. Dental amalgam will be a major topic of discussion at the upcoming third meeting of the Conference of the Parties to the Minamata Convention on Mercury, to be held in November. Since the EU has mandated a ban on using dental amalgam for children under 15, pregnant women and breastfeeding women, it is expected that other countries will follow.
The study, titled “Mercury contamination from dental amalgam”, was published in the June 2019 issue of the Journal of Health and Pollution.