Mercury vapor released from amalgam fillings has been associated with brain and neurological damage, especially among young people. It has been linked to kidney damage and damage to the digestive tract as well. (Photo: Steve Heap/Shutterstock)

2014-2-14 | News Americas

CHAMPIONSGATE, Fla., USA: The International Academy of Oral Medicine and Toxicology (IAOMT), a nonprofit health organization advocating for mercury-free dentistry, has released a new report on the safety of dental amalgam. Among other aspects, the report suggests that dental amalgam fillings may cause mercury poisoning in genetically susceptible populations.

According to IAOMT, dental amalgam contains up to 50 percent mercury. While it was once thought to be inert, health authorities worldwide, including the Food and Drug Administration, have acknowledged that dental amalgam releases low levels of elemental mercury vapor. Ever since, numerous studies have attempted to determine whether these levels are safe.

For instance, animal studies and human trials have demonstrated that mercury vapor from amalgam is rapidly absorbed and distributed throughout the body, becoming concentrated in organs, and is transferred to breast milk. In addition, some studies have suggested that susceptibility to mercury toxicity differs among individuals based on multiple genes. In the report, IAOMT stated that in the past decade at least six common genetic variants have been identified that appear to convey increased susceptibility to mercury toxicity from dental amalgam. However, not all susceptibility genes have been identified yet. 

"These findings may help explain the amalgam controversy ― why some people seem to be harmed by their mercury fillings, while others appear to be fine, and why amalgam studies have shown inconsistent results, leading authorities to presume the product is safe," IAOMT stated in a press release. 

Today, efforts are underway throughout the world to phase down or eliminate the use of mercury dental amalgam. Norway and Sweden, for example, have already banned the use of dental amalgam, and Germany and Canada advise against its use in pregnant women and children. In autumn last year, the Minamata Convention on Mercury, an international treaty initiated by the United Nations Environment Programme to reduce emissions and releases of the toxic metal into air, land and water and to phase out many products that contain mercury, was signed in Japan. Since October 2013, 94 countries have signed the convention. 

The report, titled "New Science Challenges Old Notion that Mercury Dental Amalgam is Safe," was published in the February issue of the Biometals journal.