Track 8 :48 if you feel anything while I'm working just let me know, I think we got you sufficiently numb here
1:00 sound of drilling
Dr. Ray Orzechowski is a dentist in Concord.
When patients come to him with a cavity, the kind of filling they get depends on how deep the cavity is, what tooth it's in, and how much they want to spend.
But basically, they have two choices.
They can get what's called a composite.
It mimics the color of a tooth and is made up of plastic materials.
Or patients can get a silver colored filling called amalgam.
Amalgam fillings are made up four different metals; half of it is a mixture of silver, copper, tin, and zinc.
The other half is mercury.
The EPA estimates dentists nationally use about 34 tons of mercury every year.
And when those fillings are going in and coming out, some of that mercury can get loose.
Track 1 :30 so our initial means of capturing all that amalgam is these traps right here, these chair side traps, basically a lot of the larger pieces of the amalgam are captured right here
Dr. Orzechowski's office is like most others in the state.
The first line of defense in catching the bits of mercury before they head down the sewer is what's called a chair side trap.
Track 6 sound of vacuum pump
To catch the even finer particles that get passed the chair side trap, Dr. Orzechowski has a vacuum pump with more screens and filters, in the office's basement.
He says he's not sure exactly how effective all of this equipment is in keeping mercury out of the wastewater stream.
Track 5 1:24 I can't tell you what percentage we are saving here, but obviously it's significant.
But Paul Lockwood with the state Department of Environmental Services says studies suggest that chair side traps alone are not getting the job done.
Track 1
:11 chair side traps catch about 77 percent of the amalgam scrap dentists generate when he drills teeth, puts in amalgam "yada yada", so roughly 77 percent is retained at the trap, the other 23 percent therefore gets into the wastewater, that either goes to the septic system or down to the treatment plant, neither of which we want
When mercury gets into the sewer system, bacteria can change it to its toxic form, methylmercury.
That's the really harmful mercury that works its way up the food chain, into plants, birds, fish, and humans.
In fact In New Hampshire, there's an advisory warning people about the dangers of consuming certain kinds of fish.
That mercury is not all coming from dentist's offices, but some of it could be.
And DES officials say some towns with high levels of mercury in their wastewater have actually traced it back to dentist offices.
Keith Hickey is the town manager in Bedford.
He says a few years ago, Bedford found the levels of mercury in their wastewater were above acceptable levels.
1:00: we did some testing on each pipe to identify what area the mercury was coming from
Hickey says the results were clear.
2:15 we actually tested about 27 different buildings and we found the common thread were dental offices in these building and that's when we wrote the letters to the dentists offices and told them the issues we were having
Hickey says the letters encouraged dentists to install special separators that can capture almost all of the mercury before it gets into the pipes.
He doesn't know how many followed through, but he says mercury levels have since remained low.
In New Hampshire, DES officials estimate that dentists dispose of about 250 pounds of amalgam every year.
They estimate that about 64 pounds get passed the traps.
DES doesn't know how much of that amalgam contains mercury.
Doug Bogan is with Clean Water Action.
6:35 obviously power plants are a huge issue but we shouldn't lose site of the other sources, we want to get rid of them as best as we can, we know where the dentists offices are, we know they can collect the mercury, why not do it
3 years ago, New Hampshire passed a law requiring dentists to install what are called "amalgam separators".
These separators can be up to 99 percent effective in capturing disposed amalgam.
Although New Hampshire was the first state to pass such a law, the mercury waste is still not regulated.
One reason is that dentists don't agree on the standards. .
DES wants dental offices to capture 99 percent of mercury they dispose of.
The New Hampshire Dental Society has lobbied successfully for 95 percent.
Dr. Skip Homicz is the president of the New Hampshire Dental Society.
1:22 to be sure 0 is always good, we don't mind striving for perfection, the reality is at some point practicality slips in, at this point we get most of it out, I think separators are a good idea, and I think if we look at the way we've gone about it, I'm pleased with it.
Plus, Dr. Homicz says dentists will have to foot the bill.
Amalgam separators cost about 1200 dollars to buy and about 130 dollars a year to operate.
3:05 and then there's the question of efficacy, it's a political hot potato, we are a profession that's evidence based and data driven, and the amount that these separators are going to take will be really small in proportion to the amount we already get out with our recycling techniques now, so when we look at costs, I don't hear anyone complaining but it is something we want to get right
DES officials hope to have the final rules in place by the end of this year.
Track 6: sound of basement
Track 55: this is an amalgam separator, its just one more level of filtration, I don't know how it works, I know nothing about it, I haven't gotten the information yet
Dr. Orzechowski's building does have an amalgam separator down in the basement.
The 29 inch high, 10 inch wide filter belongs to the dentist in the office next door.
Dr. Orzechowski says as soon as DES approves the final regulations, he'll get one too.
For NHPR news, I'm RK
