Putting Into Place the BMPs for Amalgam Waste Frederick Eichmiller, DDS VP & Science Officer Delta Dental of Wisconsin

Amalgam Material A mixture of elemental mercury with powdered silver-tin-copper alloy Mercury combines with silver and tin to form stable strong intermetallic compounds Powder (~50%) Liquid (~50%) Silver 63% Mercury 100% Tin 23% Copper 13% Zinc <1% Ag3Sn + Hg  Ag2Hg3 + Sn7-8 Hg

The Amalgam Revolution Early attempts with lead, tin and bismuth The “Amalgam War” of 1850 Dentists manufacturing amalgam G.V. Black formula (1890s) The first amalgam standard (1920) Modern alloys (1960s)

Lost “most used” status between 1998 & 1999 Utilization in North America is dropping at a constant rate Some European are countries eliminating use Global demand remains fairly constant

Alternatives

Amalgam Most cost effective from cost-service standpoint Still only “underwater dentistry” material Still frequently the Tx of choice in some situations

Human Toxicity What kind of Hg is it? What’s the route of exposure? What’s the dose?

Mercury: Man’s Deadly Servant National Geographic October 1972 J. Osborne

Biological Activity 70 trace elements in human body 35 have no biological activity Mercury has no biological activity Carcinogen: no positive human results Teratogens: highly positive, numerous systems J. Osborne

Liquid Mercury Very low absorption on skin Less than 0.01% absorption J. Osborne

Liquid Mercury (continued) No toxic effect when swallowed Less than 0.01% absorption Miller-Abbott (bowel obstruction) tube breaks 2% to 3% Pre-1900s drink a pound of Hg for constipation 7 lbs. Hg ingested (1/2 pint) took 10 days to clear J. Osborne

Liquid Mercury (continued) Bizarre forms Inject subcutaneously, intramuscular and intravenously Cause local inflammation, abscess and gangrene Patient does not see doctor for years Rarely causes severe mercury toxicity

Inorganic Mercury HgCl2 mercuric chloride (corrosive sublime) Chemical catalyst, preservative, treatment for syphilis Hg2Cl2 mercurous chloride (calomel) Diuretic and laxative, electrodes HgO mercuric oxide (montroydite) Batteries HgS mercuric sulfate (cinnabar) Red tattoo color, native ore of Hg Hg(ONC)2 mercury fulminate Contact detonators J. Osborne

Organic Mercury Alkyl Aryl Phenyl methyl - food chain, shellfish, ethyl - preservative Aryl aromatic series anti-fungal on seeds Phenyl prevent mildew J. Osborne

Organic Mercury Methyl mercury: Very toxic 90-95% absorbed in gut half-life 70-90 days Hg enters waterway Methylation by microorganisms Hg concentrated as it moves up food chain (tuna, shark, and swordfish) J. Osborne

Organic Mercury Ethyl mercury, preservative Thimerosal (mercurochrome) controls microbial growth 0.003-.01% used in: Soaps Shaving cream Hyper allergic cosmetics Ear flush Multidose vaccines Gamma-globulin shots Ophthalmic solutions Shampoos Nasal sprays J. Osborne

Organic Mercury Aryl Aromatic series anti-fungal for seeds Highly toxic 90-95% absorption in gut Widely used in agriculture J. Osborne

Mercury Vapor 80% absorbed in lung Significant toxicity when inhaled Accounts for most occupational and home exposures Acute toxicity is rare, but can occur Large dose causes acute pneumonitis, renal failure, seizures and neurological dysfunction J. Osborne

Mercury Vapor Sun light → UV light ← J. Osborne

Hg Sources 50% of the mercury released to the environment comes from human activity Of that amount: 53% is emitted from combustion of fuels for energy production and 34% is from the combustion of waste 13% from all other sources, including manufacturers and consumers Dentistry contributes less than one percent EPA Data

2001 Hg Use in Products Electric Other Lighting 7% 9% Electronic Measuring and Control Devices 28% Dental 14% Other 7% Electronic Switches 42% Electric Lighting 9% EPA Estimates

Common Mercury-Added Products

Hg in Products Hg content in common products: Toothpaste 3.8 ppb Deodorant 1.35 ppb Soap 25 ppb Laundry detergent 2.4 ppb Kool-Aid 6 ppb Mountain Dew .158 ppb Hampton Roads Sanitation District

USGS/ICE CORES

Dental Use of Mercury No organic or inorganic mercury is used in dentistry or in dental amalgam Restorations in 1999 required approximately 35 tons of elemental Hg in the U.S. The use of amalgam and mercury in dentistry continues to drop at a fairly constant rate (58% from 1979-99)

(Publicly 0wned Treatment Plants) The Dental Hg Trail Chairside traps and vacuum filters (78% efficient) Amalgam placements and replacements 6.5 ton Hg 29.7 ton Hg Sewers & POTWs (Publicly 0wned Treatment Plants) VanDeven JA & McGinnis SL Water, Air, and Soil Pollution (2005) 164: 349–366

The Dental Hg Trail Hg emissions 0.1 tons Incinerated biosolids 1.0 tons Hg Hg emissions 0.1 tons Sewers & POTWs POTW effluent 0.3 Tons Hg Grit solids 1.6 tons Hg 6.5 tons Hg Total Bioavailable Up to 0.4 tons Hg Beneficial use biosolids 3.6 tons Hg VanDeven JA & McGinnis SL Water, Air, and Soil Pollution (2005) 164: 349–366

So what’s dentistry’s relative contribution? Tons/Yr Municipal Waste Combustors Industrial Boilers Hazardous Waste Combustors Chlor-alkali Plants Portland Cement Kilns Geothermal Power Dental Coal Utilities

Various Cities’ Estimates of Mercury Loads (% of Total System Loads) Coming From Dental Facilities 76 80 60 34 40 26 13 14 11 20 9 Boston Seattle S.F. Minn/St Paul Cleveland Duluth Palo Alto

Typical Mercury Influent Loadings to a POTW (Metro Boston) Infiltration 33% Dental Offices 13% Water Supply <1% Corrosion Septage DITP Recycle Stream 7% Residential Sewage Inflow 11% Unknown Commercial 20% Permitted Industries 3%

Why is Mercury an Issue for Municipal Sewer Systems? Plant performance and environmental conditions at outfalls closely scrutinized Many POTWs are committed to beneficial re-use of biosolids as fertilizer and soil amendment Cities operating combined sewers facing new restrictions on storm water flows

Why is Mercury an Issue for Municipal Sewer Systems? Fish consumption advisories in 50 states Discharge limits are being lowered nationwide Mercury “Virtual Elimination Strategies” are gaining attention in NE, Great Lakes, other locations

The Regulatory Process EPA’s maximum mercury allowed in surface water is 0.001 µg /L of mercury per liter for states located along the Great Lakes and 0.05 µg /L for other states. (µg/L = parts per billion) States may use more stringent limits than EPA regulations.

Municipal Wastewater Treatment Facilities’ and Dentistry Municipal POTWs are receiving more stringent mercury limits for their discharge This requires them to begin to look “upstream” for additional sources of mercury Dental offices have been identified by many cities as a significant mercury source to their systems NACWA Position: “Pollution prevention efforts targeting sources of mercury should focus on dental offices and medical facilities (hospitals)”

They have a problem and they need our help! The Unfortunate Facts While our overall contribution to bioavailable Hg is very small, our contribution to an individual wastewater treatment facility averages approximately 40%. Treatment facilities have a growing problem meeting their stricter discharge requirements. They have a problem and they need our help!

The Solution to Pollution is Not Dilution

What about Mercury in Amalgam? “While we recognize that dental amalgam is a safe material for filling cavities, its waste should be handled properly, recovered and recycled just as we do with other waste products.” Dr. J. Bramson, Executive Director, ADA July 2002 Press Release

So what can your office do today?

ADA Recommended Best Management Practices (“BMPs”) for Dentists

What are the BMPs? Use pre-capsulated alloys Recycle used capsules Salvage, store and recycle amalgam Recycle extracted teeth with amalgam restorations (following disinfection) Use disposable chair side traps to retain amalgam; they can be recycled Install and use amalgam separators

What are the BMPS? (continued) Clean or replace screens, traps and filters regularly Store amalgam wastes in separate airtight, labeled containers Recycle all amalgam wastes through an amalgam recycler (including used capsules) Use non oxidizing vacuum line cleaners

BMP Video

Practices to Avoid Never use bulk mercury for amalgams Never pour bulk elemental mercury waste in the garbage, red bag or down the drain Never place amalgam waste of any kind (including extracted teeth with amalgams) in the biohazard (red) bag, the trash or the sharps container

More Practices to Avoid Never rinse traps, filters, or screens over or down the drain, or empty into a waste basket Never disinfect teeth or any item containing amalgam with any method that uses heat

More Practices to Avoid Never decant liquid in which amalgam has been stored down the drain Never rinse tools used to place or carve amalgam over the drain Never clean spills of elemental mercury with a vacuum cleaner

Proper Use/Maintenance of Existing Traps is an Important Amalgam Capture Mechanism

ADA Recommended BMPs for Dentists Use non oxidizing agents or cleansers when flushing and cleaning dental suction systems

In-Office Separators Sedimentation Filtration Ion Exchange

Sedimentation From suction pump To sewer Scrap

Sedimentation + Filtration From suction pump To filter Scrap To sewer Filter canister

Sedimentation + Filtration + Ion Exchange From suction pump To filter Scrap To sewer Filter canister Ion column

The Current ISO Test Run a 10 g sample of amalgam powder through the separator with 1 liter of water Capture 95% of the total mass of amalgam powder Repeat with a system that is full

Separator Results Name Company Method Cost Empty / Full Amalgam Collector R&D Services Sed $350 99.9 / 99.9 % Asdex Avprox, Inc. Filtr $215 99.1 / 99.4 % BullfroHg DRNA Technologies Sed/Filt $100/mo 99.9 / 99.4 % Durr 7800 Air Techniques Centrifug $4,000 98.1 / 97.7% Eco II Metasys $29/mo 98.2 / 97.5 % Hg 5 Solmetex Sd/Fl/IonExch $500 99.4 / 99.3 % Hg 10 $6,000 99.9 / NT % MRU $150/mo MSS 2000 Max. Separation Syst. $3,000 99.7 / 98.9% Rasch 890-400 AB Dental Trends $2,730 RME 2000 Rebec $1,895 99.7 / 99.7 % Fan et al. JADA 2002;133:577-589

Separators come in many different shapes and sizes; one size does not fit all!

Asdex Amalgam Separation System Mfr Installation Location Features American Dental Accessories $229/unit $79/filter Chairside (recommended) One unit per chair (recommended) Monthly-quarterly replacement of filters (workload dependent) Dimensions: Diameter = 3” Height = 9”

Installation Location Solmetex Hg5 Unit Mfr Installation Location Features Solmetex Hg5 $695/unit $150/filter cartridge Between chair and vacuum pump Handles up to 10 chairs Operates using combination of physical settling and chemical filtration Replace filter cartridge every 6 mos (or when full) Hg10 for larger offices Dimensions: 10” x 13” x 29”

Solmetex Hg5 High Volume Unit Mfr Installation Location Features Solmetex Hg5 $695/unit $250/filter cartridge 20% discount available to dental society members Between chair and vacuum pump Designed for larger offices/higher wastewater flows Replace filter cartridge every 6 mos (or when full) Hg10 for larger offices Dimensions: 18” x 22.5 x 28”

Installation Location MRU Mfr Installation Location Features DRNA, Inc. $1,800/year lease (includes service/replace-ment costs Between chair and vacuum pump (can be at outlet) 120V AC (to pump treated effluent) Capacity of 6-16 chairs (flow dependent) Utilizes sedimentation, filtration, ion exchange Dimensions: 12” x 16” x 24”

Installation Location R&D Amalgam Collector Mfr Installation Location Features R&D Services $495/unit (CH9, 12) (can be emptied and reused) Chairside (CH9 and12) Central location, immediately upstream from vacuum pump (CH18) Outlet height needs to be calibrated and adjusted to flow rate; decant as needed Daily valve adjustments to remove treated effluent Dimensions: 6”x6” x 9” (CH9) 6”x 6” x 12” (CH12)

Installation Location Rasch 890 Mfr Installation Location Features AB Dental Trends $1190/unit $596 per replacement unit At outlet of vacuum system (wet system) or outlet of air/water separator (if already installed) 1 unit serves 12 chairs Canister replacement 18 months 4 l/min flow rate Upgrade canisters available for additional Treatment Dimensions: 12.75”x 10.15” x 28.5”

Installation Location ECOII Mfr Installation Location Features Pure Water Systems $160+ $288 annual exchange and recycling Between chair and vacuum system 1 unit/5 chairs Annual Container exchange Internal mercury recycling program Utilizes specific GREEN & CLEAN M2 cleaner Dimensions: 8.7” x 8.7” x 13.8”

Installation Location REBEC Systems Mfr Installation Location Features Rebec (4 units) $1895-2995/unit $395-495/settle tank Between chair and vacuum system (not designed for chairside installation) Units sized to handle different # of operatories; typical replacement recommended annually

Guardian Amalgam Collector Mfr Installation Location Features Air Techniques $1,500-$3,225 After vacuum pump (drains by gravity Replace collection container every 6 months Dimensions: 6.3”x 10.5” x 7.5”

Installation Location Amalgam Boss Mfr Installation Location Features Hygenitek $695 Chairside or central location before vacuum pump Replace unit annually Sedimentation/ chemical filtration Recycling program includes disposal costs Dimensions: 12” x 20”

Practical Issues for Selection of Amalgam Separators Cost Effectiveness (Short and Long Term) Maintenance, Reliability Solids Handling and Disposal Integrity of Vacuum Systems

Practical Issues for Selection of Amalgam Separators (contd) Space and Utility Requirements Dental Office/building Constraints Regulatory Considerations Ease of Maintenance and Replacement Effect on Other Equipment

Typical Amalgam Separator Installation Locations

Separators Need to Be Maintained to Operate Effectively… Amalgam, other waste buildup in air/water separation chamber

Who Should Install A Unit? Licensed Plumber recommended Licensed Electrician may be needed for systems utilizing pumps (depending upon application) May be arranged by dental dealer (depending upon local code requirements, and lease requirements)

Space and Utility Requirements Physical Dimensions of typical units Height: 9-28” Width/diameter:3-12” Length 8-24” Installation locations (relative to existing vacuum pump and air/water separators) Electrical Power Requirements: Typically 110V if not utilizing vacuum system)

Dental Office Constraints Basement vs. Office level installations Access to Centralized plumbing Locations Multi-chair installation requirements Tenant/Landlord Issues

Other State/Local Regulatory Requirements to Check… Plumbing Code requirements for separators Amalgam Waste Handling Requirements Approved Amalgam Separator list for your state, county or municipality

Amalgam Separator Buyer’s Checklist Number of Operatories? Amalgam restorations placed or removed per day? Office operations (No. days/week)? Dental practices/types located in your building? Do you own or lease your space? Would lease stipulations affect installation of a separator? Source: Kevin R. McManus; P.L. Fan, Ph.D. Hanu Batchu, Purchasing, Installing and Operating Dental Amalgam Separators: Practical Issues, JADA

Amalgam Separator Buyer’s Checklist What terms are included for utilities maintenance? Do you operate wet/dry cuspidors? Is sufficient space available to the air/water/separator drain line and sewer line connection? Access to electrical power (voltage) Size and material of existing sewer connection

Amalgam Separator Buyer’s Checklist Do you operate wet or dry vacuum system? Will any warranty be affected by third party installations? Is the vacuum system dedicated to your office? Location of the vacuum system? Space available adjacent to vacuum system (height, length and width)?

Amalgam Separator Buyer’s Checklist Recommended installation location Maximum flow rate Life-cycle cost† In your group practice, who is responsible for: Water/sewage/utilities? Equipment servicing and maintenance? Amalgam collection/recycling?

MAXIMIZING VOLUNTARY REDUCTIONS IN DENTAL AMALGAM MERCURY Reduction in Mercury Discharges EPA # E0000127 PI-98765101-0                                                                             Environmental Assistance Center Marie Steinwachs, Director Frederick Eichmiller, DDS Co-Investigator

Goals Determine whether significant reductions in mercury discharges from dental offices could be achieved through voluntary best management practices (BMPs) Determine what effect BMPs have on mercury load to wastewater influent, effluent and biosolids To assess the level of knowledge and compliance before and after BMP training

Partners Funding and support was provided by: U.S. Environmental Protection Agency American Dental Association Foundation Springfield Public Works Department Greater Springfield Dental Society The University of Missouri Extension’s Office of Waste Management (now the Environmental Assistance Center)

Why Springfield? Commitment of staff resources from the Springfield Public Works Department and the Greater Springfield Dental Society Low existing level of BMP usage and few amalgam separators Modern treatment facilities with little storm water loading and good access for sampling

Design Influent and effluent samples collected at two treatment facilities using EPA method 1669 Total mercury determined by EPA method 1631 at Frontier Geosciences lab Biosolid analysis done on monthly blended samples using EPA method 245.1 Pre-BMP sampling on wastewater done for 4 months, biosolid for two years Intervention was a 1/2-day training seminar on BMPs followed by mailings and office visits

Intervention ½-day course provided on BMPs for dentists and office staff Participants received a DVD, wall poster with best management practices, a brochure of other available resources, and articles including: Dental mercury hygiene recommendations ADA Guidelines on Amalgam Accumulations in Dental Office Plumbing Summary of Recent Study of Dental Amalgam in Wastewater Missouri Dept. of Natural Resources determination of status and options for various types of dental waste List of amalgam recyclers

Questionnaire A questionnaire was distributed to dentists by the Greater Springfield Dental Society and Environmental Assistance Center in February 2006 Collected baseline data on amalgam use and management practices. The questionnaire was a list of 34 questions adapted from a national survey of dental office practices conducted by the ADA. A follow up survey was distributed to members of the Greater Springfield Dental Society (GSDS) in February 2007 to measure any changes in management practices after the education efforts as reported by area dentists.

Biosolid Results No significant difference in biosolid levels after the April 2006 BMP training

Influent Results No significant change after BMP training for NW plant with 3 dental offices

Influent Results Highly significant reduction in loading to SW plant with approximately 90 dental offices

Effluent Results No significant change in effluent loading after BMP training for either treatment plant

Survey Results 35% of respondents (25) reported that they did not use dental amalgam. Dental amalgam use decreased 5% from the year before. A significant decrease (from 70% to 30% ) in improper disposal of capsules in regular waste was observed 16% increase in recycling of non-contact scrap, 41% increase in recycling of contact scrap 10% increase in the practice of placing non-contact scrap into medical waste containers, and nearly an 18% reported increase in placing contact scrap in medical waste

Traps and Filters 23% decrease in the practice of disposing of chairside trap contents with regular waste (42% to 19%) 21% increase in the recycling of trap contents (from 29% to 50%) A decreases (from 39% to 21%) in the practice of placing filter contents in with regular office waste Most of the respondents, 85% (up 20% from the year before) reported using vacuum pump filters An increase (41%, up from 23%) in pump filter users who reported placing filter contents in a container with medical waste

Conclusions The practice of BMPs in the area dental offices resulted in a measurable and significant reduction in mercury load to the influent wastewater of the treatment plants. The practice of BMPs in the dental offices did not result in a measurable change in biosolid mercury levels. The practice of BMPs in dental offices did not result in a measurable change in mercury load to effluent treatment water. Better training needs to be provided to prevent amalgam waste from being mixed with medical waste for disposal

Line Cleaners The following did not appear to mobilize Hg from amalgam particulate: All-In-One E-Vac Evacuation Cleaner EZ-Zyme Gobble Plus Green and Clean MAXI-EVAC ProE-Vac Purevac Sani-Treet Plus Stay-Clean Super-Dent Turbo Vac Line Flush VacuCleanse VAC-U-EZ Source: Naval Dental Research Institute

ADA’s Amalgam Waste Program Label gray/silver container “Amalgam Waste for Recycling” Store amalgam dry (not under fixer or other solutions) Utilize USPS or parcel delivery service to ship container to qualified recycler Keep written records of the date of the shipment, the approximate mass of waste being shipped, and the name and address of the recycler

ADA Amalgam in Plumbing Waste Initiative ADA has prepared “Guidelines on Amalgam Accumulations in Dental Office Plumbing” Includes guidance on new office design features Pipe sample taken from MA dental office 2/03

ADA Guidelines are intended to apply to the following circumstances: When plumbing work is being done in areas where waste may be likely to adhere; When plumbing work is being done near areas where waste may accumulate and waste may be dislodged; During major operatory renovations; During demolition work; Whenever the pipes are cleaned out or a dentist monitors adhered waste at the request of third parties.

ADA Amalgam in Plumbing Guidelines (New Offices) Use of some basic design guidelines can help minimize collection and buildup of amalgam in office plumbing

Today, Dentists Have Better Information and More Choices These BMPs will help ensure that dental offices properly handle and dispose of these wastes The options and support for collecting and recycling amalgam waste have increased significantly over past few years

Thank you! And if All Else Fails… http://www.ada.org/prof/resources/topics/amalgam.asp Thank you!