Dental amalgam waste: what practices must do

The rules dental practices have to meet

Article 10 of the Mercury Regulation sets out the core duties. It came into UK law from the EU and now sits in assimilated law in Great Britain. NHS England's Chief Dental Officer wrote to all registrants in 2018 explaining the changes. The rules that matter most for waste are these:

• Dental facilities where amalgam is used, or where amalgam fillings or teeth containing them are removed, must have amalgam separators. All separators in use since 1 January 2021 must retain at least 95% of amalgam particles.
• Separators must be maintained according to the manufacturer's instructions.
• Amalgam may only be used in pre-dosed encapsulated form. Bulk mercury is prohibited for dental practitioners.
• Practitioners must see that amalgam waste, including residues, particles, fillings and contaminated teeth, is handled and collected by an authorised waste management establishment or undertaking.
• Practitioners must not release such waste into the environment, directly or indirectly, under any circumstances.

The separator duty falls on the operator of the dental facility, and the waste duty on dental practitioners. A practice owner may arrange the contract, but associates working there should know the arrangement is in place.

Northern Ireland works differently

The EU regulation continues to apply directly in Northern Ireland under the Windsor Framework, and an amending EU regulation adopted in 2024 restricts the use of amalgam there. Practices in Northern Ireland should check the current position with the Department of Health, and we have not tried to summarise it here.

In the surgery: three amalgam waste streams

Chairside waste. Amalgam residues, excess from capsules and removed filling material go into a dedicated amalgam container. HTM 07-01 asks for this stream to be kept separate, with a sealable rigid container, clearly marked as dental amalgam, showing the relevant hazard symbols and holding a mercury suppressant. A chairside pot left unlidded through the day defeats the purpose, as mercury gives off toxic vapour.

Used capsules. These go in the same stream. They often contain a small residue, so they do not belong in sharps or in general waste.

Extracted teeth containing amalgam. HTM 07-01 says these are disposed of as dental amalgam waste, and mentions tooth pots for holding them. Burning releases mercury, so keep them out of sharps bins and other waste sent for incineration.

Keep two amalgam containers if your practice needs them. HTM 07-01 says infectious and non-infectious amalgam should go in separate bins. The code differs too: non-infectious amalgam is 18 01 10*, while infectious amalgam takes 18 01 03* together with 18 01 10*.

At the sink: the separator

The separator is both a piece of equipment and a waste source. Sludge and collection canisters are amalgam waste, handled under the same code.

Three things commonly go wrong. The canister is left past its replacement point, because nobody owns the job. The service visit is recorded, but not the waste that came out of it. And a new unit gets installed with no record showing it meets the retention standard. Keep the manufacturer's maintenance schedule with your waste file, along with the certificate or data showing the 95% retention figure. Staff should also know the separator does not make the drain a permitted route for anything else.

Spillage is its own hazard. Where amalgam or elemental mercury is spilled in a surgery, follow your spill procedure, keep the area ventilated and do not use a vacuum cleaner, as this can spread mercury vapour into the room. Old dental surgeries sometimes have jars of elemental mercury left from the days before encapsulation. If you find one, leave it closed and in place and get a specialist to deal with it.

Other chemical waste in a dental practice

Amalgam is not the only stream. Solvents and disinfectants, including ethanol based products, become chemical waste when discarded in bulk, or past date, and must not go into clinical or municipal bins. The hazardous entry for chemicals from human healthcare is 18 01 06*, with 18 01 07 for the non-hazardous counterpart.

Photochemicals and X-ray film take codes from chapter 9 of the technical guidance, so a practice that still runs wet processing will have that stream as well. Gypsum moulds and casts are a separate stream under HTM 07-01. Keep them apart from the amalgam stream.

Veterinary practices using amalgam should note that WM3 also directs them to 18 01 10*, even though it sits in the human healthcare section.

Storage and packing before collection

Bins awaiting collection should sit somewhere secure and away from patient areas, with their lids closed. HTM 07-01 also sets out packing and marking points for amalgam, and a container certified for transporting mercury may be needed. Your waste contractor should confirm which applies.

Do not decant one container into another to save bin space. It exposes staff to vapour, and it removes the certainty about what is in each container.

Paperwork for amalgam collections

Amalgam moves as hazardous waste, so a consignment note goes with it in England. The note should show the correct code, the weight and the hazard. You keep one copy and hand two to the carrier. The practice keeps its record for three years, alongside the related documents, on the premises that produced the waste.

Rules differ elsewhere. Scotland uses special waste consignment notes with a code from SEPA. Northern Ireland uses codes issued by its environment agency. In Wales, premises producing over 500kg of hazardous waste a year must register, and a consignment note is needed regardless.

Before signing with a contractor, check the public register for their carrier registration, and ask where the amalgam will go. Recovery is the usual aim for this stream, so ask them to confirm that it is what happens to yours.

The inspection file

A small file answers most questions an inspector might ask. It holds the separator's data sheet and service records, your amalgam policy, the waste contract, the carrier's registration check and three years of notes. Keep a simple log of collections and bin changes, and name who is responsible when the practice manager is away.

Our dental practices page covers the wider waste picture for a practice, while mercury and heavy metal disposal covers old mercury stock and similar one-off finds.