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Though dental amalgam is considered by the American Dental Association as a safe, affordable and durable material for use in filling cavities and restoring teeth, the importance of its proper disposal cannot be understated.

That’s due to the environmental concerns presented by mercury, a chemical element present in amalgam. Dental amalgam is a mix of liquid mercury and a powder that is made up of silver, tin, copper, zinc and other metals.

Due to those concerns, proper waste management and disposal best practices must be closely adhered to anywhere dental amalgam waste is collected in bulk.

Fortunately, the American Dental Association (ADA) has offered best practices for dental offices and other who handle and encounter amalgam waste on how to dispose of and recycle the material.

What happens when dental amalgam isn’t handled properly

Those best practices have been shared for critical reasons.

When dental offices mishandle or do not follow best practices for managing their amalgam waste, it can in fact find its way into the environment, typically though wastewater systems via office spittoons. This could put people at risk of exposure to mercury and mercury poisoning.

Once the amalgam waste travels through wastewater systems and reaches sewers, it eventually arrives at a municipal sewage treatment plant. These facilities have a 90 percent efficiency rate of removing amalgam from the water, according to the EPA.

It is estimated that less than 1% of the mercury that is released into the environment comes from dental practices, but precautions are still necessary.

However, if the amalgam waste is not successfully removed, it remains in the facilities’ treated water and can be discharged back into the water stream. That is when it becomes an environmental hazard.

Mercury can also seep into the ground or enter the air. When it is disposed of improperly, there is a chance that the mercury in dental amalgam can end up in a landfill where, over time, it could leak into the ground and enter groundwater systems. It could also be burnt at a landfill with other items, causing it to pollute the air.

Mercury, whenever it could come into contact with people, is health concern.

Use amalgam waste disposal and recycling best practices to prevent problems

This is why the ADA has compiled a list of best practices, including dos and don’ts, for any dental practice and other facilities. The organization has also provided a guide to integrating these methods and strategies into everyday routines.

The ADAs best practices include using chairside traps, amalgam separators, regular inspection and cleaning of traps in the office, as well as use of a commercial waste service to recycle and dispose of the collected amalgam in the appropriate manner.

And, don’t forget, as this blog has explained before, compliance with the Environmental Protection Agency’s final rule regarding amalgam separation is required.

Do: Amalgam waste best management practices

The following is a list of what to do when it comes to handling and disposing of dental amalgam waste, according to the ADA. The ADA also provides some practical guides to implementing these suggestions.

• Do use precapsulated alloys and keep in stock different capsule sizes.
• Do recycle used disposable amalgam capsules.
• Do save, store and recycle scrap amalgam, also known as non-contact amalgam. Place the scrap in a wide-mouthed container and label it clearly as “Non-Contact Amalgam Waste for Recycling.” Ensure the container is sealed well.
• Do save amalgam pieces from restorations after they are removed and the recycle their contents. As with scrap amalgam, other amalgam pieces should be stored in a wide-mouthed container, sealed tightly when full and clearly labeled.
• Do use chairside amalgam pieces from restorations after they are removed and recycle their contents. If the trap from a chairside separator is part of a unit used only for hygiene purposes, then the trap can be placed in regular garbage. For reusable traps, it’s recommended to empty the contents but not to rinse the trap under running water, as this could allow dental amalgam to enter the water system.
• Do recycle teeth that contain amalgam restoration. Be sure to ask you recycling service provider whether those teeth need to be disinfected.
• Do recycle as much amalgam as possible.
• Do use line cleaners so that dissolution of amalgam is minimal.

Don’t: Amalgam waste best management practices

The following list is comprised of what the ADA suggests not to do when handling amalgam waste:

• Don’t use bulk mercury.
• Don’t place used disposable amalgam capsules in biohazard containers.
• Don’t put scrap - or non-contact - amalgam waste in biohazard containers, infectious waste containers (red bags) or in regular garbage containers.
• Don’t put contact amalgam waste in biohazard containers, infectious waste containers (red bags) or in regular garbage containers.
• Don’t rinse devices containing amalgam over drains or sinks.
• Don’t dispose of extracted teeth that contain amalgam restorations in biohazard containers, infectious waste containers (red bags), sharps containers or regular garbage.
• Don’t flush amalgam waste down drains.
• Don’t use bleach or chlorine-containing cleaners to flush wastewater lines.

Amalgam separators are a requirement, not just suggested guidance

EPA regulations now require any place that removes dental amalgam to have amalgam separators installed, maintained and monitored. That includes any dental practice, hospitals, schools, clinics, mobile units and similar facilities that are owned by federal, state or local governments.

Amalgam separators are equipment that can remove particles of amalgam from wastewater through one or a combination of several processes, which can include sedimentation, filtration, centrifugation, chemical removal.

The ADA states amalgam separators that comply with ISO 11143. Equipment that meets this standard, which is set by the International Organization for Standardization (ISO), can separate 95 percent of the amalgam waste that is discharged into sanitary sewer systems.

In addition, always follow the recommendations set by the amalgam separator manufacturer.

Partner with DRNA

DRNA is the dental community’s complete regulatory solution provider. We are proud of our status as the number one environmental compliance partner for dentists and take seriously our commitment to responsible dental waste recycling and disposal.

Contact DRNA to learn about this commitment and how we strive to provide each of our customers the very best dental waste management services.