First it was cement kilns, then municipal sludge burners had to control mercury emissions. And the next industry to dray the mercury-hating eye of the EPA: your dentist.

The EPA announced on Monday, Sept. 27, 2010, that it intends to propose a rule to reduce mercury waste from dental offices. Dental amalgams, or fillings containing mercury, account for 3.7 tons of mercury discharged from dental offices each year, according to the agency. The mercury waste results when old mercury fillings are replaced with new ones. The mercury in dental fillings is flushed into chair-side drains and enters the wastewater systems, making its way into the environment through discharges to rivers and lakes, incineration or land application of sewage sludge. Mercury released through amalgam discharges can be easily managed and prevented.

The agency believes that dental offices will be able to use existing technology to meet the proposed requirements. Amalgam separators can separate out 95 percent of the mercury normally discharged to the local waste treatment plant. The separator captures the mercury, which is then recycled and reused.

Until the rule is final, the agency is encouraging dental offices to voluntarily install amalgam separators. Twelve states and several municipalities already require the installation of amalgam separators in dental offices.

Approximately 50 percent of mercury entering local waste treatment plants comes from dental amalgam waste, the agency said. Gone are the days when dental amalgam waste at the dentist's office was given to children to play with while they wait for an appointment.

The EPA expects to propose a rule next year and finalize it in 2012.

SOURCE: EPA press release