Minnesota Pollution Control Agency employee Carol Hubbard and Clancy, the only mercury-detecting dog in the United States, paid a visit Friday to St. John's Lutheran School in Wykoff. See page eight for the story. (Tribune photo by Gretchen Mensink Lovejoy)

By Gretchen Mensink Lovejoy

Spring Valley Tribune

Clancy is a heavy metal teacher. He’s not into Guns ‘N’ Roses, Ozzy Osbourne, Linkin Park or having his ears and nose pierced.

He wags his tail as he enters the school building, excited to see the students.

Clancy, a black and chocolate Labrador retriever-hound mix, is the Minnesota Pollution Control Agency’s (MPCA) mercury-detecting dog. He’s trained to find hidden sources of mercury in schools and industrial and public facilities.

Currently, he and his handler, Carol Hubbard, are employed in the MPCA’s Mercury-Free Zone Program (MFZP), a mercury elimination program initiated after MPCA staff discovered large quantities of mercury in some Minnesota schools. Clancy sniffed out deliberately-placed containers of mercury while the pair visited St. John’s Lutheran School in Wykoff on Friday as the school pledged to become a Mercury-Free Zone Program participant. Removing the element without the program’s assistance can cost anywhere from $5,000 to $250,000 and result in short-term school closure. According to the MPCA’s December 2002 newsletter, "The program’s goals are to reduce the risk of potential mercury exposure to students and school staff, prevent releases of mercury to the environment by eliminating mercury from schools, and to educate students and staff about the dangers of mercury."

Mercury can affect nervous system functions. The brain, spinal cord, kidneys and liver suffer damage from vapors released invisibly into the indoor atmosphere. The Howard Lake-Waverly Herald and Winsted-Lester Prairie Journal quoted Hubbard in an article about Clancy. "Mercury poisoning causes nerve damage, and miners working underground who used to be afflicted by it would babble to themselves, and develop uncontrollable shaking of their hands from the nerve damage." The article went on, "In fact, the term ‘mad as a hatter’ and the character featured in Alice in Wonderland are actually referring to mercury poisoning. During the 1800s, hat fitters would use mercury to shape men’s hats. This would eventually poison them, hence the term ‘mad hatter.’" Schools often overlook sources of mercury contained within their facilities — sources such as broken fever thermometers, mercury-bearing blood pressure cuffs, mercury-bearing laboratory thermometers and barometers, "forgotten" mercury inside drawers and cabinets, lab chemicals and accumulations inside school laboratory sink U-bends. Hubbard cited an example of how those sources affect staff. "Teachers who are ‘chained’ to the same classroom year after year are breathing mercury vapor." Broken fluorescent light tubes also emit mercury vapors that have the potential to get into the air or the waste stream. Once in the waste stream, it enters lakes and streams. Bacteria can produce methylmercury, a neurotoxin that accumulates in the flesh of fish. The toxins then can poison any human or animal that ingests the fish. The MPCA’s website maintained, "Removing mercury from schools eliminates the chance that mercury from them will find its way into Minnesota’s environment. In this way, the MPCA’ s Mercury-Free Zone Program is helping limit mercury contamination of Minnesota’s lakes and streams, the fish that live in them, and the people who eat those fish."

By signing the MFZP pledge, a school agrees to inventory the mercury-bearing items in its buildings, turn in mercury and mercury-bearing items for recycling, implement a phase-out plan, purchase mercury-free alternatives and commit to an educational program for students, faculty and other staff about mercury and other persistent bioaccumulative toxins. That’s where Hubbard and Clancy come in. Clancy is the only mercury-detecting dog in the United States. He was chosen from the Ramsey County Humane Society by members of the St. Paul Police Department Canine Unit in December 2000. The department had inspected more than 200 dogs before choosing Clancy. He was elected because he eagerly searched for a tennis ball in the way canine police officers search for objects, drugs and people. Dogs have proven useful in mercury detection in other countries, prompting their incorporation in programs in the United States. "Experience in Sweden showed that use of mercury-detecting dogs is both a cost-effective way to find mercury and an excellent tool for teaching students about the dangers of mercury. The MPCA’s Mercury-Free Zone Program is modeled after the successful Swedish program. In 1999, two specially trained dogs checked 1,100 schools in Sweden. As a result, about 1.4 tons of mercury were removed from these schools." Hubbard trained Clancy to detect mercury by playing hide-and-seek for hours each week — she hid mercury, he found it, and when he succeeded and sat down to indicate his discovery, she rewarded him with a tennis ball.

He can smell the vapor from as little as half a gram of mercury, the amount a fever thermometer spills when broken. Since mercury is the only metal that is liquid at room temperature, it is easier for Clancy to detect it when the air is warmer — it emits more vapor. Hubbard confirms the invisible vapor’s presence with a Lumex unit designed to measure the concentration of mercury in the air. The machine was originally developed to sense mercury leaks in Soviet submarines that used mercury as ballast, and can identify concentrations as low as two one-billionths of a gram, or two nanograms.

What about Clancy’s health?

The MPCA stated, "Clancy may have been at greatest risk from exposure to mercury during his training. Since then, Clancy has found relatively little mercury in the schools and industrial facilities he’s checked." A veterinarian examines the dog every three months, drawing blood and taking hair samples. The results have been below the detection limit each time he’s been screened. MPCA scientists speculate that Clancy will not have contact with high concentrations for long enough to cause poisoning or damage. "While old mercury spills pose the greatest threat of occupational mercury exposure for people, Clancy will never be exposed to these potentially high levels for extended periods," the article said. Hubbard admitted experiencing some short-term memory loss as a result of working with mercury during the 13 years she’s been employed with the MPCA. She quipped, "Nobody cares about me," because her audiences question threats to Clancy’s health more readily than her own, though she is tested for poisoning as often as he is. However, her assignment to train Clancy two years ago has proven rewarding each time they investigate a school and find hidden elemental mercury caches. The MPCA’s newsletter concluded, "By locating spills so they can be cleaned up, Clancy is helping to assure that people will not continue to breathe mercury vapor from the spills."

For more information on Clancy and how to arrange an inspection, contact Chris Butler at (218) 723-2358 or (800) 657-3864.