The dental profession has always emphasized preventive care. Now, this spirit of prevention needs to extend to preventing the release of amalgam to the environment.
Amalgam is typically 50 percent mercury by weight. However, the mercury in amalgam chemically combines with other metals to render the mercury stable and safe for use in dental applications.
Given that dental amalgam contains mercury, dentists must safely dispose of amalgam waste to ensure it does not inadvertently become incinerated or disposed of in a way that would release mercury back into the environment in a free form.
Amalgam is, and will likely remain, an efficient and effective restorative material. Dentists will continue using it for the foreseeable future, although its use continues to gradually decline. Even if dentists completely stopped using amalgam for new fillings, the removal of old amalgam will continue to generate waste.
At dental offices, vacuum systems discharge amalgam to the sewerage system when dentists place or remove amalgam fillings. Mercury pollution has caused the Wisconsin Department of Natural Resources to issue a statewide fish consumption advisory.
The DNR requires sewage treatment facilities to implement a mercury minimization program to address mercury in wastewater. A primary element of this program is reducing the amount of amalgam discharged by dental offices.
The WDA also has identified best management practices for amalgam waste disposal. While important, best management practices alone may not be enough for regulated wastewater systems to meet the Environmental Protection Agency’s discharge standards. Some local wastewater systems will require dentists in their service areas to install amalgam separators.
If your community requires an amalgam separator, they are available from several suppliers and are decrease amalgam in wastewater by 95 percent or more. See more information below. The WDA endorses HealthFirst for this service.
More dentists are considering purchasing amalgam separator units to decrease the amount of amalgam in the wastewater leaving their offices. Although this decision is a positive one for the environment, it is not necessarily an easy one for the dentist. While the WDA endorses HealthFirst for amalgam separators, there are a variety of providers to choose from.
These units differ in terms of capacity, physical dimensions, amalgam removal process, how captured amalgam is removed and recycled, how easily they are serviced and how often, and how much they cost to buy and operate. Without some guidance, evaluating amalgam separators can be like comparing apples and oranges. This guide was designed to help dentists identify their specific needs and the key aspects of their office systems that determine which separator unit(s) will be most suitable for their operations.
Step 1: Decision flow sheet
By answering a series of questions relating to your office set-up, the dentist is led to an initial list of separator units that will probably work for his or her office.
These questions include:
The dentist’s answer to each of these questions will lead him or her to an appropriate set of potential separators for evaluation.
Step 2: Separator comparison matrix
This matrix allows a comparison of the initial list of separator units generated in the decision flow sheet above, helping the dentist zero in on which unit(s) is the best for his or her dental practice. The matrix provides both qualitative and quantitative comparisons of 15 different amalgam separator units produced by 11 different companies. The units have been commercially available since early 2004. It also provides telephone and Web site contact information for each manufacturer.
The evaluation criteria include:
After working through the decision flow sheet (Step 1) and the matrix (Step 2), the dentist should have a good idea about which unit(s) is most suitable for his or her specific circumstances. Hopefully, this exercise will also result in a list of more specific questions for your dental equipment supplier or the separator manufacturer. Working together with your supplier or manufacturer’s rep, you should now be sufficiently prepared to purchase an amalgam separator unit that will meet your needs and protect the environment for many years to come.
The WDA frequently receives member inquiries regarding the selection and installation of amalgam separators. Presently, certification under ISO 11143 (as issued by the International Organization for Standardization) has been the standard adopted by those local sewerage districts in Wisconsin that have previously mandated separators and this standard should provide a good starting point for selection of a separator for any dental practice that has not already installed one.
The Environmental Protection Agency has announced that it intends to issue a final rule regarding its national plan for a reduction of mercury waste from dental offices before the end of 2012; this could include a national amalgam separator mandate.
While many options are available, the WDA endorses HealthFirst for amalgam separators, LB Medwaste for the removal of medical waste, and Scientific Metals for the recycling of precious metals.
Also, below is a list of amalgam recyclers. This list is provided solely as a service to members and should not be viewed, or in any way interpreted, as a recommendation or endorsement of companies included on the list. Similarly, absence of a company from the list should not be interpreted as a negative comment on that company or on the quality or suitability of its product. While the WDA strongly encourages the installation and use of amalgam separators, we assume no responsibility or liability in connection with separator selection and urge that each member conduct their own independent evaluation from among all available products.
*Note if you choose a recycler not on this list, be sure they are licensed to receive and handle these materials.
| DO | DO NOT |
| Use precapsulated alloys and stock a variety of capsule sizes | Use bulk mercury |
| Recycle used amalgam capsules | Put amalgam capsules in biohazard containers, infectious waste containers (red bags) or regular garbage |
| Salvage, store and recycle non-contact amalgam (scrap amalgam) | Put non-contact amalgam in biohazard containers, infectious waste containers (red bags) or regular garbage |
| Salvage amalgam pieces from restorations after removal (contact amalgam) and recycle the amalgam waste | Put contact amalgam in biohazard containers, infectious waste containers (red bags) or regular garbage |
| Use chair-side traps to retain amalgam and recycle their contents | Rinse chair-side traps containing amalgam over sinks or other drains |
| Recycle the contents retained by the vacuum pump filter or other amalgam collection device | Rinse vacuum pump filters or other amalgam collection device over sinks or other drains |
| Recycle extracted teeth that contain amalgam restorations* | Put extracted teeth with amalgam restorations in biohazard containers, infectious waste containers (red bags) or regular garbage |
| Use line cleaners that do NOT contain bleach or other chlorine compounds | Use line cleaners that contain bleach or other chlorinecompounds |
| RECYCLE AS MUCH AMALGAM WASTE AS POSSIBLE | FLUSH AMALGAM WASTE DOWN A SINK, TOILET, OR OTHER DRAIN |
*Confirm with your recycler whether it accepts extracted teeth. Disinfect extracted teeth by storing them in an airtight container with a solution of glutaraldehyde or 10 percent formalin until they are removed for recycling with your other amalgam waste.
Amalgam capsules
Non-contact (scrap) amalgam
Disposable chair-side traps
Reusable chair-side traps
Vacuum pump filters
Line cleaners
Use line cleaners that do NOT include bleach or other chlorine compounds.
Disinfection
Disinfecting amalgam waste for recycling is unnecessary, except for extracted teeth that contain amalgam restorations. For disinfection use glutaraldehyde or 10 percent formalin rather than bleach. Bleach dissolves amalgam and releases mercury. Use bleach only if your recycler accepts the disinfectant solution along with the amalgam waste.
*Some recyclers allow you to place all amalgam waste, including capsules, non-contact amalgam, contact amalgam, traps, filters, and teeth into the same container. If so, you may use one container labeled Amalgam Waste for Recycling. Follow your recycler’s instructions for packaging and shipping amalgam waste.
