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Take the Bite Out of Dental Amalgam Waste

Breakout Group Recommendations

One of the key efforts of the April 2008 conference was an interactive session to identify 

components of a model dental amalgam waste reduction program. Breakout groups 

discussed five topics. The groups reached the conclusions described below.

Outreach and Education

 A critical first step is meeting with dental societies. This action includes both 

meeting with officers and speaking to the general membership.

 Assembling a dental office database requires a variety of resources. The most

important resource is a local business directory, such as the Yellow Pages. 

Additional resources include state licenses, plumbing or building inspections, and 

occupancy permits. The database will need constant maintenance because the 

dental office population is dynamic. 

 Time needs to be allowed for education to be absorbed and for multiple 

opportunities for the message to be shared. Being open to dialogue is important 

for assuaging skepticism, answering technical questions, and addressing unusual 

situations. 

 To achieve long-term change in the culture of dentistry, dental schools and 

technical schools need to establish an awareness of mercury issues and reduction 

strategies. Therefore, contact with local dental and technical schools is strongly 

recommended. This contact includes both speaking to staff and speaking directly 

to students.

 An initial survey to identify current practices is valuable to establish a baseline for 

measuring progress.

Reduction Approach

 Programs should include both “carrots” and “sticks.” Factors affecting 

implementation include the administrative and financial capacity of the public 

agency; the size of the dental community; the amount of private, state, or federal 

support available; and existing local and state law. 

 “Carrots” include awards recognizing positive action and subsidies for installing 

separators or recycling. Awards and subsidies are great for maintaining rapport 

and speeding progress. However, they will not work alone. In most 

communities, some degree of willful disregard or simple ignorance is likely to 

persist. For these offices, “sticks”, such as reporting rules and penalties, are 

necessary.
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 The size of the community is a critical factor. Generally, the larger the 

community, the more formal the program needs to be. If a community is small 

enough that the public agency can reach every office individually, then a less 

formal approach is more likely to be effective. 

 Public agencies often have broad legal authority, making existing legal authority 

sufficient to take action in most cases. This authority includes the authority to 

abate a public nuisance, to prevent pass-through, or to require pollution 

prevention plans. However, detailed new rules would focus attention and 

facilitate compliance. General requirements, rather than individual control 

mechanisms, are likely to be sufficient because requirements will not change from 

place to place. 

 The recommended criterion for being included in the source reduction program is 

whether the dental office conducts any placement or removal of amalgam. This 

criterion is simple and maximizes environmental protection.

 Finally, communities should investigate opportunities to coordinate amalgam 

work with other environmental or health programs. For example, amalgam 

management could be consolidated with work regarding lead foil, X-ray film 

development chemicals, radiation safety, or medical waste.

Separator Standards

 Generally, implementing the ISO standard is effective and efficient. Uniformity 

and certainty benefit the market. Requirements beyond the ISO standard require 

substantial effort for uncertain environmental benefits. If communities desire a 

standard more stringent than the ISO standard, then they should consider using 

the lists that other communities, such as King County, Washington, have already 

developed. 

 Certainly, the ISO standard needs to be reviewed for opportunities for 

improvement. Also, the testing of devices by certification bodies is valuable. 

However, these tasks are most appropriate when done on a national basis, rather 

than locally.

 Importantly, implementation of a device that meets the ISO standard is not the 

only relevant factor for ensuring good performance. Effort is also needed to 

ensure that devices are matched to appropriate circumstances. Dental supply 

companies are developing expertise in this area. However, this expertise is 

focused on protecting the dental practice, rather than maximizing environmental 

protection. Therefore, developing some capacity to review the appropriateness of 

installations would be valuable. 
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 Finally, even if the separator is appropriate for the circumstances, it will not be 

effective unless it is maintained. Separator manufacturers and suppliers need to 

clearly articulate maintenance requirements, dental offices need to maintain the 

devices as indicated, and public agencies need to review the maintenance that is 

occurring. Just as with separator selection, some expertise regarding appropriate 

maintenance would be valuable. Inspections and reports are techniques to obtain 

information regarding actual maintenance practices. Of course, some risk of 

adverse consequences, such as penalties, needs to be present for cases where 

maintenance is chronically poor. 

Ensuring Compliance

 Reporting, certifications, and inspections each have important roles for ensuring 

good performance. Considerations include: maintaining an awareness of mercury 

issues among dental office staff; the amount of information needed by the public 

agency to measure progress; the administrative burden for the public agency; and 

the administrative burden for dental offices. 

 Generally, for showing the amounts of mercury waste recycled and the date of the 

shipments, annual reports are appropriate. This report would include 

certifications indicating continuing implementation of best management practices

and proper maintenance the amalgam separator, if one is installed. Inspections 

are necessary to verify the reported information and maintain familiarity with the 

dental community. Inspections of each office should occur at least every two 

years.

 For ensuring compliance, both initial and continuing training is critical. 

Therefore, public agencies need to work with continuing education providers to 

ensure coverage of mercury issues. 

 Sampling dental office discharges is not recommended, except in cases of unusual 

problems.

 One aspect of ensuring compliance is being aware of changes to dental office 

locations over time. To track dental offices as they open, close, and move,

monitoring occupancy permits and business directories should occur.

Evaluating Progress

 Knowing initial conditions is important for evaluating progress. These initial 

conditions include both dental office practices and influent, effluent, and biosolids 

concentrations. Over time, collecting data regarding these parameters on regular 

schedule is necessary.
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 Influent and effluent concentrations are likely to decrease slowly. Therefore, 

public agencies need to be prepared to track data over a long time.

 Tracking the total mass or volume of mercury being shipped from dental offices 

for recycling is valuable. However, obtaining timely and uniform data will be 

challenging. 

 Tracking the amount of mercury being collected would be optimum, but obtaining 

the mass of mercury in every shipment of mercury waste is likely to be 

impractical.

 Sewer cleaning and rehabilitation may release mercury accumulated over long 

periods. These temporary loads of mercury complicate evaluating long-term 

trends. Therefore, being aware of cleaning and rehabilitation projects is important 

for understanding these trends.

 As with other topics, maintaining an accurate list of current dental offices is 

important, along with information showing their current compliance status.