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BEST MANAGEMENT PRACTICES (BMPs) 

FOR DENTAL OFFICES 

 For Minimization of Mercury and Imaging Discharges to the Sewerage System 

By Dental Care Providers

Prepared by the Idaho State Dental Association 

Introduction and Regulatory Background: 

The Idaho State Dental Association has prepared this guide to assist dentists on how to best manage the 

disposal of dental office wastes. Dental office wastes (amalgam particles, waste mercury, fixers, 

developers, x-ray film packets, and chemiclave chemicals) typically cause toxic chemicals (mercury, 

silver, lead, developer solution chemicals, and chemiclave solutions) to enter our streams, sewers, and 

landfills. In addition to the environmental benefits of proper waste management, through pollution 

prevention, dentists can also reduce the regulatory requirements associated with dental wastes by 

voluntarily complying as outlined. 

Mercury discharges to the environment are receiving significant attention throughout the United States 

and in Idaho. Local city and county wastewater agencies have mechanisms to regulate dental office 

discharges through existing sewer use ordinances and the local pretreatment program. The ISDA Dental 

BMP Program has been developed to address mercury amalgam and other environmental concerns and 

regulatory requirements. Specifically, the ISDA has developed this program to help Idaho dentists 

properly manage dental wastes to ensure compliance with applicable environmental, biomedical, 

occupational health, and transportation regulations. 

This program is a two-tiered process that relies on relatively easy-to-implement and cost-effective BMPs 

with additional or optional BMPs included to provide further waste management and pollution prevention 

options that are available. 

This guide has been approved by the Idaho State Dental Association Board of Trustees. 

You should share this information, or a summarized version of it, with your local wastewater treatment 

facilities. It is anticipated that wastewater facilities representatives may visit some dental offices within 

their service areas from time to time to ensure the appropriate BMPs are in place. You can assume any 

visit will consist of confirmation that staff are trained and are performing the minimum BMPs. The 

request we make of inspectors is that they make prior arrangements with the dental office before an 

inspection visit which will allow for minimum disturbance of office routine. 

The target date recommended for Idaho dental offices to have this BMPs plan in place is October 1, 

2004. 
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Best Management Practices 

Recommended Minimum BMPs 

This set of recommended minimum BMPs relies on two principal concepts: 

1) Dentists using a minimum of dental waste products in order to minimize the amount of waste generated 

by the dental office. 

2) Properly collect, store, and ship dental wastes 

Minimizing the use and recycling of dental waste products is the preferred approach because this reduces 

the amount of, and costs associated with, dental wastes. Local and state recycling vendor information is 

contained in an appendix to this document to make it easy to contact recyclers that can help. 

To dispose of dental wastes, if recycling is not an option, proper disposal as hazardous waste is necessary. 

 Many local, city, and county wastewater agencies have hazardous waste collection programs designed for 

small generators of wastes such as dental care providers. For example, Ada County operates a 

conditionally-exempt small quantity generator (CESQG) program that can accept up to 200 combined 

pounds of scrap amalgam, x-ray fixer solution, and lead foils per month. 

 AMALGAM WASTES 

1) Limit the amount of amalgam used to the smallest appropriate size for each restoration. 

2) Eliminate all use of bulk elemental mercury (also referred to as liquid or raw mercury). Use only 

pre-capsulated dental amalgam. Any unused bulk elemental mercury must be recycled or hauled away as 

hazardous waste. It must never be poured in the regular trash, infectious waste (red bag), or down the 

drain. (See # 6) 

3) Change or clean chair-side amalgam traps frequently. If cleaning the traps, flush the vacuum 

system before changing the chair-side trap. Don't rinse the amalgam traps over drains or sinks. 

Consider dedicating specific chairs to amalgam placement and removal to minimize the number of 

amalgam-containing traps that need to be managed (traps associated only with hygiene chairs can be 

disposed of in the regular trash).

4) Change vacuum pump filters at least once per month or as directed by the manufacturer. This 

action will also improve suction and extend the life of the vacuum pump.

5) All amalgam waste must be recycled or hauled away as hazardous waste: 

Χ Non-contact amalgam (scrap); 

Χ Contact amalgam (e.g., amalgam removed from patients and extracted teeth containing amalgam); 

Χ Leaking or unusable amalgam capsules. 

Amalgam waste must never be put in the regular trash, put in with infectious waste (red bag), or flushed 

down the drain. Chair-side traps or vacuum pump filters containing amalgam must never be rinsed over 

drains or sinks. 

6) Used or empty amalgam capsules can be placed in the regular trash.

7) Store amalgam waste as directed by your recycler or hazardous waste disposal program. This 

typically includes being in covered, segregated, and clearly labeled airtight plastic containers. Check with 

your recycler for any other specific requirements such as disinfection steps or necessary dry storage.
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8) Maintain a log of amalgam waste generation and recycling/disposal. Documentation of all 

amalgam waste recycling and disposal must be obtained from your recycler or hazardous waste hauler, 

kept on file, and made available upon request. 

X-RAY FIXER AND DEVELOPER 

1) Properly manage X-ray fixer waste. Fixer waste is considered a hazardous waste because of its high 

silver content. However, fixer is easily recyclable. Recycling is the management method recommended 

by regulatory agencies. There are two suitable methods of managing fixer waste: 

a) Keep used fixers separate from used developers. 

b) You may use a silver recovery unit for you developing system; or 

c) You may give, sell, or pay someone that operates a silver recovery unit to take your 

 fixer. 

If you dispose of your fixer off-site, collect and store it in a closed plastic container labeled: Hazardous 

Waste -- Used Fixer--Contains only fixer. Many recyclers want to be sure that the liquid does not contain 

developer. If it does, it could actually remove silver from the recycling equipment. The liquid that has 

run through a recovery unit can be disposed of down the drain. 

In addition, some photo developing companies will accept x-ray fixer from dental offices. You may wish 

to check with those companies in your area.

2) Do not use products to solidify x-ray fixer or other dental waste. These products simply transfer 

the waste to a different wastestream because regular trash is taken to the landfill. 

3) Do not mix X-ray developer solutions with fixer solutions. Waste developer can be washed down 

the drain, if it is not mixed with fixer. Flush the drain thoroughly as you discharge developer down the 

drain. 

Some units mix the fixer and developer after they are spent. The resulting solution is hazardous and 

should be disposed of as hazardous waste (see amalgam waste for more information on hazardous waste 

disposal options). However, you may purchase an adapter kit to keep the fixer and developer separate. 

LEAD FOIL AND LEAD SHIELDS 

1) Recycle or dispose of lead foil that shields x-ray film or protective lead shields as hazardous 

waste. These materials should never be disposed of in the regular trash because they are hazardous 

waste, unless they are recycled for their scrap metal content. Companies which recycle amalgam or fixer 

may also accept lead waste. Eastman Kodak has a special mail in program for dentists to recycle lead 

foil. A list of metal reclaimers is given in the appendix. 

2) Do not use lead foil or give lead foil to patients to melt down for fishing weights. This is not a 

recommended practice . Dental offices are especially encouraged not to give the lead foil to patients. 
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CHEMICLAVE WASTE 

1) Move away from chemiclave sterilization to autoclaves. Normal use and discharge of chemiclave 

solutions is acceptable although discouraged. Flush following disposal with several gallons of water so 

that it does not sit in the sink trap or introduce a slug of material to the sewer system. 

2) Use up or dispose of discarded materials properly. Dental offices should buy only the amount of 

chemical sterilizer that you need: this will eliminate the need to dispose of the excess material. If you 

switch to an autoclave and has a supply of unused formaldehyde, you should give this to a dentist who 

still uses a chemiclave. The local wastewater agencies would like to avoid a large "slug" of formaldehyde 

at any one time. 

LABELING 

1) Properly label the container in which you store your hazardous waste. Although you should check 

with your disposal company, typically these containers must be labeled with the words "hazardous waste" 

with a description of the waste. Example: "Hazardous Waste - - Contains only used fixer, for recycling 

only." 

The date you start filling the container should be written on the container or on a label. Standard labels 

are commercially available. Make sure you keep a written record of any material you send or deliver to a 

recycling entity. Be sure to request a "Certificate of Recycling or Disposal." This could be simply a note 

on their letterhead that they received "x" gallons of fixer and that it would be processed in their silver 

recovery unit. 

ADDITIONAL RECOMMENDED BMPs 

1)________ Use disposable amalgam traps instead of reusable traps, and have them recycled or 

 hauled away as hazardous waste if they contain amalgam waste. 

2)________ Clean or replace sink traps and sumps, taking care to avoid spillage of the contents 

 from plumbing parts. Removed sludge must be recycled or hauled away as 

 hazardous waste. 

3)________ Use, when appropriate, based on your professional judgement, mercury-free 

 alternatives to amalgam (e.g., gold, ceramic, porcelain, composites, polymers, glass 

 ionomers). 

4)________ Install and properly maintain a dental amalgam separator or other technologies to 

 reduce amalgam discharge. 

5)________ Implement a program to have mercury-containing thermostats, switches, and 

 fluorescent light bulbs recycled when they are replaced. Thermostats and switches 

 should be replaced with mercury-free alternatives. 

6)________ Describe on attached pages any additional BMPs for mercury discharge minimization 

 hat you may have identified and plan to implement.