Topic: A Sweet Tooth for Mercury?

Air Date: July 23, 2006 

Background: 

For over 150 years, mercury-containing fillings (often called “silver” or “amalgam”) have 

been used extensively to fill dental cavities. Four metals— mercury, silver, copper and 

tin—primarily comprise amalgam, with mercury being approximately 50 percent by 

weight. While use of mercury-free fillings is becoming more prevalent, most dentists in 

the United States still use mercury-containing amalgam. 

Current dental practices result in significant quantities of mercury being released from 

dental offices. Sludges generated by the treatment facilities are often incinerated, 

releasing significant amounts of mercury emissions into the atmosphere, which 

eventually pollute our waterways and fish. In 2004, the US Environmental Protection 

Agency estimated that dental clinics nationwide use 34 tons of mercury annually. 

In response, DEM has developed a program to address concerns about the amount of 

mercury being released into public wastewater treatment systems and septic systems of 

dental offices that are not connected to sewers. 

By July 1, 2008, Rhode Island dentists will be 

required to install amalgam separators in their 

facilities. The separators are installed in 

plumbing system and remove amalgam from 

new or removed fillings that would otherwise 

go down the drain. Amalgam separators are 

cost effective and filter mercury out of the 

wastewater before it leaves the dental office. 

According to industry sources, the installation 

of separators at dental offices could prevent 99 

percent of the mercury releases that go down 

the drain for approximately $50-$100 per 

month. 

The RIDEM dental certification program, that 

will soon be available to all RI dentists, will 

allow them to register and self-certify the 

installations of their separators. A simple 

electronic reporting form will minimize the 

As of July 1, 2008 Rhode Island dentists will be 

required to install amalgam separators in their 

facilities. 

EarthWatch 

Rhode Island
reporting requirements while allowing dentists to become partners with RIDEM in 

helping to quantify the amounts of mercury captured in their separators. An annual 

update will allow RIDEM to track the reductions over time. Information about Best 

Management Practices and non-mercury dental options will be available on the 

Department website for the public and the dental community. 

DEM worked with the Narragansett Bay Commission, Clean Water Action and 

representatives of the RI Dental Association to develop this program. DEM patterned the 

program after the NBC best management practices for the management of waste dental 

amalgam. Rhode Island dentists served by NBC are required to follow stringent, best 

management practices to prevent mercury pollution, including installing amalgam 

separators in their plumbing systems to remove excess amalgam from new or removed 

fillings that go down the drain. However, since more than half the dentists in the state are 

not part of the NBC service area, they have not yet taken similar steps. 

Dangers of Mercury 

Mercury makes its way into water bodies, where it is converted to methylmercury. 

Highly toxic methylmercury accumulates in many edible fish species, which are a major 

source of human mercury exposure in the U.S. Exposures to pregnant women are of 

particular concern because methylmercury can cross the placenta and enter the fetal 

brain. Children exposed to even low levels of mercury before birth can experience serious 

neurological and development deficits. Recent information is also evolving concerning a 

link between mercury exposure and an increased risk of adverse cardiovascular effects. 

Mercury and Rhode Island 

Most of the mercury that is deposited in RI’s 

water and soils comes primarily from man-made 

air emission sources such as solid waste 

incinerators and coal-fired power plants outside 

the state and the Region. Rhode Island has 

initiated aggressive programs to address key 

sources of mercury pollution that the state can

control. The programs promote the collection and 

recycling of mercury-containing wastes, including 

spent mercury switches from cars, used mercury 

glass fever thermometers, used fluorescent and 

high intensity discharge lamps, elemental mercury 

and mercury-added products from middle and 

high schools, and used mercury-added measuring 

and other devices. 

Reducing dental mercury is the next big step in making Rhode Island mercury free. 

Reducing dental mercury is also part of a regional mercury strategy. Recently revised 

projections to “virtually eliminate” mercury emissions in the Region were set by the 

Conference of New England Governors and Eastern Canadian Premiers. A goal of 

having 75 percent of dentists in the region install dental amalgam separators is expected 

Dr. Roger Turkel prepare to his assistant 

prepare to give a filling to a patient.
by the end of 2007. Using best management practices and an outreach and education 

program, RI dentists will be able to impact and significantly reduce the amount of 

mercury entering our air and waterways. 

Interviews: 

• Beverly Migliore, DEM Supervising Environmental Scientist 

• Dr. Roger Turkel, Dentist and champion of amalgam separators 

Channel 10 reporter Lisa Purcell (right) interviews DEM’s Beverley Migliore (left) on the important safety 

precautions that should be used when dealing with dental amalgam.