Debate Over Silver Amalgam Tooth Fillings Shifts to the Environment

A movement in the dental industry calls for phasing out silver amalgam—which contain up to 50% elemental mercury, a toxic substance—due to health and environmental concerns, the Chicago Tribune reported.  Studies on the direct impact of silver amalgam tooth fillings on human health have been inconclusive, but the preparation of silver amalgam does contribute mercury pollution to the environment, according to the Tribune.

According to a 2010 EPA estimate, about half the mercury entering municipal wastewater treatment plants comes from dental amalgam waste, and some of that mercury ends up in landfills, fertilizer, or flushed into waterways.  Once in water, it transforms into methylmercury and builds up in fish and shellfish that are then consumed by humans.  Methylmercury has been linked to health and developmental problems in pregnant women, fetuses, infants, and children.

These concerns have culminated in several recent actions:

•  Over 140 nations have agreed to a U.N. treaty calling for decreasing use of dental amalgam.
• New York University’s College of Dentistry will be putting less emphasis on the preparation and placement of silver fillings.
• Two large, nonprofit Catholic hospital chains are pressuring two leading American makers of dental amalgam to phase out mercury.
• Norway, Denmark, Sweden, Japan and Finland have either banned dental amalgam or restricted its use within the last five years.

Mercury, mercury compounds, methylmercury, and methylmercury compounds have been designated by the State of California as chemicals known to cause cancer and reproductive harm.  Companies doing business in California must provide consumers with a health hazard warning if their products contain such chemicals.

A popular alternative to silver amalgam fillings are tooth-colored resin-based composites, but many contain bisphenol-A (BPA), an endocrine disrupter that has been linked to developmental harm and has been banned from infant and children products.  BPA is currently the subject of a legal battle in California in order to determine whether or not it should be designated as a chemical known to the State of California to cause reproductive harm.

The Chanler Group represents citizen enforcers who, acting in the public interest, commence actions against businesses offering products for sale in California that contain chemicals known to cause cancer or reproductive harm without first providing the health hazard warning required by Proposition 65. Citizen enforcers bringing Proposition 65 actions in the public interest may obtain a Court Judgment imposing civil penalties, an injunction requiring reformulation of products, and/or provision of health hazard warnings. The Chanler Group has represented citizen enforcers of Proposition 65 for more than twenty years.