Your dental fillings can harm the environment if you choose cremation for your final disposition, because there’s mercury in them thar amalgams. How much mercury? A study completed by the University of Minnesota Dental School gives the surprising answer.
Mercury is a naturally occurring element in our environment. You’ll find mercury emissions in volcano eruptions. It’s also generated by man-made activities – mostly gold mining, coal combustion, iron and cement production, and in a relatively small way, by cremation.
Mercury is a dangerous neuro-toxin, which means it is toxic to the nervous system, particularly to the developing system of a fetus or young child. It’s bioaccumulative, which means mercury pumped into the atmosphere falls onto the earth through contact with rain and snow, then it runs into streams, lakes and oceans where it accumulates.
That mercury gets into food chain through fish, which is why pregnant women are warned against eating too much fish. Minnesota, with its many lakes, has had a big problem with mercury pollution (the Minnesota Pollution Control Agency calls it “water impairment”).
You may have a glass thermometer at home. The mercury inside indicates your body temperature when you hold the thermometer in your mouth. If you’ve had dental work done, such as cavity fillings and crowns, your mouth also contains mercury.
Dental amalgam is a liquid mercury and metal alloy mixture used to fill cavities caused by tooth decay. It’s also underneath ceramic crowns. In 1859, the American Dental Association approved this composition for dental amalgam: silver 69%, tin 18%, copper 12%, and zinc 1%, set in 45% mercury by weight.
Mercury boils and vaporizes at 674.1º Fahrenheit. Cremation retorts run between 1,200º to 1,800º F. Any mercury in dental work becomes an emission too fine to filter out. Mercury vapor goes out the retort’s venting and up into the atmosphere.
When Minnesota legislators wanted to reduce dangerously high mercury emissions in the state by having morticians or dentists remove fillings from the mouths of dead people prior to cremation, the funeral industry freaked. It became important to get a handle on how much mercury actually gets into the atmosphere by cremation.
A pioneering report on “Quantifying Mercury Emissions From Crematoria in Minnesota” was presented at the 2015 meeting of the Cremation Association of North America (CANA). The presenters were Dr. Michael LuBrant, Director of the Program of Mortuary Science at the University of Minnesota; Dr. Sandra Myers, Associate Professor in the School of Dentistry at the University of Minnesota; and Rebecca Place with the Minnesota Pollution Control Agency (MPCA).
All three sat down with me to do an interview for A Good Goodbye Radio. We discussed how and why the study was done, what they found out, and what it all means. That interview is now posted at FuneralRadio.com. You can listen to the 22-minute interview here.
Some highlights of the study: Out of 1,000 subjects examined (actually the dental records of 1,000 living people), 23,088 teeth were evaluated for dental amalgams and scrupulously measured. They found an average of 6.8 crowns per subject aged 63-79. Their calculations came out to 2.3 grams of mercury per subject. In 2014, Minnesota had a 57% cremation rate.
Long story short: The Minnesota Pollution Control Agency estimated mercury emissions from Minnesota crematoria in 2012 to be 125 pounds. Using the data gathered in the research spearheaded by Dr. Myers, the MPCA calculated the emissions in Minnesota for 2014 to be 95 pounds – in this one state for just one year.
Let’s do some math. If we have 75 million U.S. Baby Boomers that each have 2.3 grams of mercury in their mouths, and 50% of this population choose cremation (although it will probably be a higher rate of cremation), let’s see… That’s 37.5 million people choosing cremation. Multiply that by 2.3 grams of mercury and that equals 86,250,000 grams of mercury emissions for this segment of the population.
That equates to 190,148.7 pounds of mercury released into the atmosphere, just by Baby Boomers in the United States alone. Other countries have higher rates of cremation, but who knows the state of dental amalgams in those other folks’ mouths?
It’s something to think about before you choose cremation, if you’re concerned about your personal impact on the environment.
What’s the dental profession doing to reduce the use of mercury in fillings? Why do dentists still use it? Sandra Myers said, “The dentist is caught in a bind. There’s a cost difference between amalgams and the tooth-colored filling material that’s not covered by insurance. Amalgams are cheaper, easier to use, and last longer than the tooth-colored material. The insurance industry drives these things.”
You can access Dr. Myers full report and other information on this issue through this link to the Minnesota Pollution Control Agency website.
For more information about cremation, get a copy of the new book, Hail and Farewell: Cremation Ceremonies, Templates and Tips. It retails for $10.00 (plus shipping and NM sales tax as applicable) and discounts are available on bulk purchases. It’s available at Amazon.com, BarnesandNoble.com, and AGoodGoodbye.com: Order your copies today!
The book’s title refers to the last line of an ancient elegiac poem written by the Roman poet Gaius Valerius Catullus approximately 2,000 years ago. He mourns the death of his brother, who died while Catullus was traveling abroad. Upon his return, he sadly addresses his brother’s cremated remains, “… with brotherly weeping. And forever, brother, hail and farewell.”