Featured Research

from universities, journals, and other organizations

Older dental fillings contain form of mercury unlikely to be toxic, study finds

Date:
December 12, 2009
Source:
American Chemical Society
Summary:
A new study on the surface chemistry of silver-colored, mercury-based dental fillings suggests that the surface forms of mercury may be less toxic than previously thought.

Older mercury-based dental fillings contain a form of mercury that scientists say is unlikely to be toxic.
Credit: American Dental Association

A new study on the surface chemistry of silver-colored, mercury-based dental fillings suggests that the surface forms of mercury may be less toxic than previously thought.

It appears online in ACS' journal Chemical Research in Toxicology.

In the study, Graham George and colleagues note that mercury-based fillings, also called amalgams, have been used by dentists to repair teeth for well-over a century. In recent decades their use has become controversial because of concerns about exposure to potentially toxic mercury. However, mercury can potentially exist in several different chemical forms, each with a different toxicity. Prior to this report, little was known about how the chemical forms of mercury in dental amalgam might change over time.

Using a special X-ray technique, the scientists analyzed the surface of freshly prepared metal fillings and compared these with the surface of aged fillings (about 20 years old) from a dental clinic. Fresh fillings contained metallic mercury, which can be toxic. Aged fillings, however, typically contain a form of mercury, called beta-mercuric sulfide or metacinnabar, which is unlikely to be toxic in the body.

The scientists found that the surfaces of metal fillings seem to lose up to 95 percent of their mercury over time. Loss of potentially toxic mercury from amalgam may be due to evaporation, exposure to some kinds of dental hygiene products, exposure to certain foods, or other factors.

The scientists caution that "human exposure to mercury lost from fillings is still of concern."


Story Source:

The above story is based on materials provided by American Chemical Society. Note: Materials may be edited for content and length.


Journal Reference:

  1. George et al. The Chemical Forms of Mercury in Aged and Fresh Dental Amalgam Surfaces. Chemical Research in Toxicology, 2009; 22 (11): 1761 DOI: 10.1021/tx900309c

Cite This Page:

American Chemical Society. "Older dental fillings contain form of mercury unlikely to be toxic, study finds." ScienceDaily. ScienceDaily, 12 December 2009. <www.sciencedaily.com/releases/2009/12/091209121206.htm>.
American Chemical Society. (2009, December 12). Older dental fillings contain form of mercury unlikely to be toxic, study finds. ScienceDaily. Retrieved August 20, 2014 from www.sciencedaily.com/releases/2009/12/091209121206.htm
American Chemical Society. "Older dental fillings contain form of mercury unlikely to be toxic, study finds." ScienceDaily. www.sciencedaily.com/releases/2009/12/091209121206.htm (accessed August 20, 2014).

Share This




More Health & Medicine News

Wednesday, August 20, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Raw: World's Oldest Man Lives in Japan

Raw: World's Oldest Man Lives in Japan

AP (Aug. 20, 2014) A 111-year-old Japanese was certified as the world's oldest man by Guinness World Records on Wednesday. Sakari Momoi, a native of Fukushima in northern Japan, was given a certificate at a hospital in Tokyo. (Aug. 20) Video provided by AP
Powered by NewsLook.com
Ebola-Hit Sierra Leone's Freetown a City on Edge

Ebola-Hit Sierra Leone's Freetown a City on Edge

AFP (Aug. 19, 2014) Residents of Sierra Leone's capital voice their fears as the Ebola virus sweeps through west Africa. Duration: 00:56 Video provided by AFP
Powered by NewsLook.com
101-Year-Old Working Man Has All The Advice You Need

101-Year-Old Working Man Has All The Advice You Need

Newsy (Aug. 19, 2014) Herman Goldman has worked at the same lighting store for almost 75 years. Find out his secrets to a happy, productive life. Video provided by Newsy
Powered by NewsLook.com
Researcher Testing on-Field Concussion Scanners

Researcher Testing on-Field Concussion Scanners

AP (Aug. 19, 2014) Four Texas high school football programs are trying out an experimental system designed to diagnose concussions on the field. The technology is in response to growing concern over head trauma in America's most watched sport. (Aug. 19) Video provided by AP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins