In 2004 the ADA agreed with the EPA that a significant portion of mercury flowing into our POTWs was from dental offices. In 2008 the ADA argued for a voluntary pretreatment reduction program. The EPA monitored mercury levels in the regulated states and waste water districts. They validated that the mercury inflows decreased by 50 percent. They monitored the ADA voluntary program. To estimate that 20 percent of dentists voluntarily installed an amalgam separator. While my research suggests a mere 2 percent.

Last month we covered the history and scale of this issue. We are deceiving ourselves if we believe that the EPA will not pass a rule to stop 50% of all mercury flowing into the 1000's of POTWs around the country. Look at the reduction in mercury levels published by Kings County after they implemented their pretreatment program. This is clearly the most logical and cost effective solution to our problem.

I wonder if we fully appreciate the legal and logistical effort it has taken for the EPA to propose this rule; Effluent Limitations Guidelines and Standards for the Dental Category; 64 pages; 28,266 words; plus a change to selected parts of the General Pretreatment Regulations? To confront the ADA, special interest groups and environmental politics in this time of unpopular government expansion. 

We need to keep this Newsletter accurate and pithy. Open4BioClean has a reference document; Analysis of the EPA proposed Rule; with links to the EPA, ADA, source documents, and objective on-line resources. The dental publications are under pressure. They have limited resources to apply to this issue. Their readers are not interested in more regulations, let alone costs to sustain the environment. They maintain editorial independence despite immense pressure from special interest groups.

I have read the rule. The 181 public comments. Spoken to the Kings County Industrial Waste Program Manager. Interviewed manufacturers and professionals. It is my privilege to bring you an informed view on this difficult issue of dental amalgam, environmental impact and what dental offices are being told to do.

These dates may be extended. This could happen if the ADA challenges the EPA in court. The EPA may take extra time (they did extend the closing dates for public comment) to modify the rule based on the comments they have received. I also know that many POTWs are being fined by the EPA for failing to meet their mercury discharge standards. They do not have the capital to upgrade their plants. Less to deal with the leaking pipes which flood (water leaks in) their plants when it rains. A serious issue I learned of while analyzing peak demand and electricity use by POTWs. Do not be misled by any media and other objectionist literature.

Once the rule is effective (see below for my opinion on legislative authority) all dentists are required to register as a DIU. If a dentist misses the deadline to register as a DIU, they are automatically registered as a (SIU) Special Industrial User. This would not be a good thing. Especially if they discharge any mercury! The oversight for a SIU includes control mechanism issuance requirement, annual inspection and sampling requirements. Here is a link to the EPA's existing regulations for the control of mercury in the United States.

I believe that all people have the potential to do good. Installing an amalgam separator is such an opportunity! Every gram of particulate mercury, and every drop of soluble mercury that does not go down the office drain is a good thing. For the POTWs who do not have to process it. For the fish, birds and the water critters that live in the POTWs waste water treatment ponds. For everyone when this water filters into our local waterways. It is without doubt the right good thing to do!   

I also understand the high tension between environmental "gooder" and environmental clean up costs. Common sense dictates that we should not flush dangerous materials down our drains. We have all seen the fish symbols where rain water runs into the drains. We have all seen do not dispose of signs for septic systems. Every dental office knows the waste water district that they fall under. I do not know how each will enforce this new rule. I think that those in environmentally sensitive areas will embrace it. I imagine that others will fear the ire of local dentists and their tax revenues. I hope that dentists will stop flushing amalgam-mercury and any other potentially harmful material down the drain soon. To use my late fathers words, "in our enlightened long term self interests". 

Congress passed the Federal Water Pollution Control Act Amendments of 1972, also known as the Clean Water Act, to “restore and maintain the chemical, physical, and biological integrity of the Nation's waters.” The CWA establishes a comprehensive program for protecting our nation's waters. Among its core provisions, the CWA prohibits the discharge of pollutants from a point source to waters of the U.S. except as authorized under the CWA. Under section 402 of the CWA, EPA authorizes discharges by a National Pollutant Discharge Elimination System (NPDES) permit. The CWA also authorizes EPA to establish national technology-based effluent limitations guidelines and standards (effluent guidelines or ELGs) for discharges from different categories of point sources, such as industrial, commercial, and public sources.

The CWA requires EPA to manage nationally-applicable pretreatment guidelines and standards that restrict pollutant discharges of wastewater indirectly through sewers flowing to POTWs. National pretreatment standards are established for those pollutants in wastewater that may pass through, interfere with or are otherwise incompatible with POTW operations. Pretreatment standards are designed to ensure that wastewater from direct and indirect industrial dischargers is subject to similar levels of treatment. In addition, POTWs are required to implement local treatment limits applicable to their industrial indirect dischargers to satisfy any local requirements.

The EPA has clear evidence to demonstrate that 50% of the mercury flowing into POTWs via the public sewers is from dental offices. The EPA can show that cost effective pretreatment technology is available. The EPA allowed the ADA to distribute amalgam BMPs, invite their members to voluntarily install ISO compliant amalgam separators and gave time for adoption to be monitored. The voluntary program has failed. The EPA has the authority to propose a pretreatment standard for mercury discharge in dental offices. I believe that the EPA will implement this rule after considering the public comments received.      

This can be achieved by installing, properly operating and maintaining, a dental amalgam separator certified to achieve at least 99.0% reduction of total mercury. Dental offices will be required to verify that the amalgam separator installed is compliant with the 2008 ISO 11143 standard. Dental offices will be expected to operate and maintain the separator following all manufacturer's instructions, and conduct inspections at least monthly to ensure all features are functional.

Dental offices can elect to not use an amalgam separator. To capture 100% of their dental water in a collection tank, like the system from Anterior Quest. This must meet the proposed numeric limit, and will be subject to the same oversight and compliance requirements for other indirect discharges.

b) Incorporation of two Best Management Practices to control mercury discharges that would not be captured by an amalgam separator. i) Scrap amalgam, including but not limited to dental amalgam from chair-side traps, screens, vacuum pump filters, dental tools, or collection devices may not be flushed down the drain. ii) Chair-side traps that may drain to a sewer must be cleaned with non-bleach, non-chlorine containing cleaners that have a pH of 6 to 8.

c) Bleach and other strong chemical cleaners will "solubilize" mercury. Significantly increasing soluble mercury discharges. The EPA proposes that evacuation system cleaners do not contain bleach, and are of a neutral (6.9) pH. I have been saying this for some time now. Refer my article on the excessive use of chemicals in the dental industry. Has the day of microbiology based evacuation cleaners finally arrived?

e) The EPA recognizes that there are offices who have amalgam separators in place (by state and local regulation) (by voluntary compliance) that are certified at a lower rate than the proposed new 99% standard. EPA does NOT propose that these offices be retrofitted with new amalgam separators. These offices will be required to comply with the new BMP's, operational and regulatory reporting standards.

Partly as none of the currently regulated states and districts include a standard for soluble mercury. Mostly as the additional cost of capturing this final 0.4% of soluble mercury with a pretreatment technology, is not reflected in the environmental advantages given to the POTWs.

A study by the president of Purves Environmental Inc., which I found in the public comment submitted by Mr. Mike Darcy of M.A.R.S Bio-Med Process Inc. suggests that the EPA are "mostly" correct. Some amalgam separators (by a combination of design and operations) allow dental water to remain in contact with the captured amalgam-mercury before it is discharged into the public sewers. The study placed 4 grams of amalgam-mercury in 125 milliliters of pure water neutral pH (6.9) and allowed it to stand for 30 days. Simulating water remaining in an amalgam separator that had captured particulate amalgam-mercury.

The volume of soluble mercury in the water was measured; Day 1: 119,000 ng/L. Day 10: 2,410,000 ng/L. Day 30: 3,110,000 ng/L. Note: The EPA limit for mercury discharge by a POTW is 12 ng/L. It would certainly be foolish to support a pretreatment technology that captured particulate amalgam-mercury, only to have it dissolve into a mix of dental water and evacuation cleaning chemicals. And then discharged down the drain. Mr Purves findings strongly supports the EPA proposal that dental offices do not use bleach for cleaning, and that their evacuation cleaner is of a neutral pH.

I am going to dig into this issue in the April Newsletter. When I will review the different "technological" approaches available for the pretreatment of amalgam-mercury. I sincerely do not believe that the EPA's goal is to have dentists comply with a rule. I believe it is to "strongly" help the dental industry to stop flushing all toxic material into the public sewers.

According to the Chicago Tribune, the ADA spent more than $2.8 million lobbying the EPA, members of Congress and other federal agencies in 2012. The MMDI estimate the ADA to be the third-biggest-spending health professionals’ lobby. On October 21, 2014, a personal dental mal-practice lawsuit was quietly settled out of court in favor of the plaintiff, Freya Koss. I see an organization fighting tooth and nail to deny every potential statement of negativity or damage that could arise from the use of amalgam-mercury. First to patients, and then to the environment.

I understand why dentists have been reluctant to accept the cost of capturing amalgam-mercury removed from patients mouths. They did not create it. They often did not put it there. Why should they pay to resolve this? It is not fair. But it is what happens when corporations avoid accountability for the long term environmental costs of their products lifecycle. I know how I feel about 320 tons of amalgam-mercury lurking in 200 million mouths. What will next generations say if we miss our chance to capture it now? When they learn that we flushed it into the trillions of gallons of water in our local water systems.