» Mercury from dental amalgam
Mercury from dental amalgam
Context - Dental amalgam, an alloy of mercury and silver, has been in use for over 150 years for the treatment of dental cavities, due to its excellent mechanical properties and durability.
Dental amalgam is the second largest use of mercury in the EU, after its use in the chlor-alkali industry.
The use of alternative materials such as composite resins, glass ionomer cements, ceramics and gold alloys is increasing, either due to their aesthetic properties or to alleged health concerns in relation to the use of dental amalgam
What are the environmental risks and indirect health effects of mercury from dental amalgam?
- Source document:SCHER (2013)
- Summary & Details: GreenFacts
How much mercury is released into the environment through its use in dental amalgams ?
Emissions from the use of mercury in
dental amalgam fillings can occur
during the preparation of the amalgams and
their subsequent removal and disposal. They can also occur when human remains
that have amalgam fillings are cremated or
In Europe, the total amount of mercury
released into the air by human sources is estimated to have been around 142 tons
per year in 2010. Natural emissions, such as those from volcanic activity or
forest fires, are estimated to be at around 87 tons per year for the same
period. By comparison, releases in the air from dental practices are estimated
to be at around 19 tons per year.
Are mercury releases caused by the use of dental amalgam a risk to the environment ?
At present there is still not enough information available to make a
comprehensive risk assessment for the environment; however some general
conclusions can be reached.
For the aquatic environment, in general,
amalgam does not represent a risk for
European surface waters. However, under
exceptional local conditions (maximal dentist dentistry, maximal mercury use, absence of separator devices), it could be that
the amount of mercury would be higher than the environmental quality standards.
In such cases, a risk for the aquatic
ecosystem could not be excluded. For soil
and air, there is still not enough data available to make an
assessment of the risk.
Is the amount of mercury present in the environment a possible health risk for humans ?
Mercury coming from
dental amalgam as well as from many
other sources present in the global environment can be taken up by the general
human population via food, water and air.
However, mercury present in the
environment from amalgams is only a very
minor fraction of the total amount of mercury that people are exposed to.
In the aquatic environment, under particular local conditions where the
concentration of mercury in the aquatic
environment is higher than the environmental quality standards, a risk of
secondary poisoning in humans through food cannot be excluded. Indeed some
mercury can be transformed into methyl mercury, which can accumulate in
organisms along the food chain. This, in
turn can cause health problems in humans if there is more mercury than the safe
level, mainly through the consumption of fish. However this risk is minimized by
the EU food legislation excluding food commodities from the market exceeding the
maximum allowed concentration of mercury and other metals.
Are the alternative materials for dental fillings safer than mercury amalgams?
In many reports it is concluded that the ecological risk of the available
alternatives is very low, with low emissions and low intrinsic toxicity. However
available information does not allow a proper comparison assessment of
amalgam alternatives. For the human
health, SCHER is again of the opinion that the indirect risks to human health
from the release of the amalgam alternatives without
mercury is low, except for alternative
materials containing bisphenol A-glycidyl methacrylate. For these materials
SCHER recommends to refer to an on-going SCENIHR mandate on the use of bisphenol
A in medical devices. Ecotoxicological information on the effects of the
products more frequently used for dental resins is practically absent and more
research on those materials is needed to make a sound risk assessment. In
addition, SCHER suggests that the chemical composition of alternative materials
should be fully declared.
This fact fact sheet is based on the preliminary opinion of the independent
Scientific Committee On Health And Environmental Risks : "Opinion on the
environmental risks and indirect health effects of mercury from dental
amalgam ", June 2013.