Minamata Convention on Mercury Dr. Theodoros Mechteridis DDS

Minamata Convention on Mercury World-wide environmental concerns over mercury led the United Nations Environmental Programme (UNEP) to draw up the Minamata Convention on Mercury, which was formally signed in October 2013. The objective of this Convention is to protect the human health and the environment from anthropogenic emissions and releases of mercury and mercury compounds. The treaty commits the world to a gradual phase-down in the use of dental amalgam but without a commitment to a specific timetable.

Measures to be taken to phase-down dental amalgam Setting national objectives aiming at caries prevention and health promotion Setting national objectives aiming at minimizing its use; Promoting the use, research and development of cost-effective and clinically effective mercury‑free alternatives for dental restoration; Educate and train dental professionals and students on the use of mercury- free dental restoration alternatives and on promoting best management practices; Discouraging insurance policies and programmes that favour dental amalgam use over mercury‑free dental restoration; Restricting the use of dental amalgam to its encapsulated form; Promoting the use of best environmental practices in dental facilities to reduce releases of mercury and mercury compounds to water and land.

What did the BDA do? BDA representatives worked through the Council of European Dentists and FDI World Dental Federation to lobby for the gradual reduction in the use of dental amalgam rather than an unworkable complete ban. We argued that a total ban could destabilise dentistry in the UK and time was needed to enable a phase down, as well as the need for comparable alternative materials for restorations. A true alternative to amalgam has yet to become available and, until it is, a ban would have adversely affected public health and an already complex service delivery process.

WORLD HEALTH ORGANIZATION Dental amalgam is used in almost all countries. A 2009 WHO expert consultation concluded that a global near-term ban on amalgam would be problematic for public health and the dental health sector, but a phase down should be pursued by promoting disease prevention and alternatives to amalgam; research and development of cost-effective alternatives; education of dental professionals and the raising of public awareness.

Scientific Committees Three independent non-food Scientific Committees provide the Commission with the scientific advice it needs when preparing policy and proposals relating to consumer safety, public health and the environment. The Committees also draw the Commission's attention to the new or emerging problems which may pose an actual or potential threat. They are: the Scientific Committee on Consumer Safety (SCCS), the Scientific Committee on Health and Environmental Risks (SCHER) and the Scientific Committee on Emerging and Newly Identified Health Risks (SCENIHR) and are made up of external experts.

Committee on Emerging and Newly Identified Health Risks (SCENIHR) According to the Scientific Committee on Emerging and Newly Identified Health Risks (SCENIHR) Opinion adopted in May 2008, dental amalgam is a safe material to use in restorative dentistry for patients. No health risk other than allergic reaction in certain individuals can be associated with the use of dental amalgam. The alternatives are not without clinical limitations and toxicological risks, and less is known about these alternatives for which available scientific data are more limited.

Revised opinion of SCENIHR Local effects Local adverse effects in the oral cavity are occasionally seen with dental amalgam fillings, including allergic reactions and an association with clinical features characteristic of lichen planus, but the incidence is low (< 0.3% for all dental materials in general) and usually readily managed.

Revised opinion of SCENIHR Systemic effects Elemental mercury is a well-documented neurotoxicant, especially during early brain development. Inorganic mercury also constitutes a hazard to kidney function. In some scientific reports the presence of dental amalgam has been suggested to be associated with a variety of systemic adverse effects, particularly developmental neurotoxicity as well as neurological and psychological or psychiatric diseases. However, the evidence for such effects due to dental amalgam is weak.

Revised opinion of SCENIHR Placement and removal of dental amalgam fillings results in transient short-time exposure to the patients compared to leaving the amalgam intact. There is no general justification for unnecessarily removing clinically satisfactory amalgam restorations, except in those patients diagnosed as having allergic reactions to one of the amalgam constituents. Recent studies do not indicate that dental personnel in general, despite somewhat higher exposures than patients, suffer from adverse effects that could be attributed to mercury exposure due to dental amalgam.

Revised opinion of SCENIHR The SCENIHR concludes that current evidence does not preclude the use of either amalgam or alternative materials in dental restorative treatment. However, the choice of material should be based on patient characteristics such as primary or permanent teeth, pregnancy, the presence of allergies to mercury or other components of restorative materials, and the presence of impaired renal clearance.

References SCENIHR 2015. The safety of dental amalgam and alternative dental restoration materials for patients and users MINAMATA CONVENTIONON MERCURY. Text and annexes. October 2013 (www.mercuryconvention.org) https://www.bda.org/amalgam http://www.who.int/mediacentre/factsheets/fs361/en/