On Tuesday, Oct. 4, the Keene State Department of Environmental Studies hosted its first guest speaker for the 2011 fall semester to talk about her work in the field of environmental studies.
The event took place in room 309 of the Young Student Center on the KSC campus and those who attended gained knowledge on the “Atmospheric Mercury Deposition in New Hampshire.”
Melissa Lombard, a Ph.D. candidate at the University of New Hampshire, presented her own dissertation from research she collected over two years on mercury deposition.
Lombard kicked off the event by explaining the historic background of the compound mercury (Hg). “Mercury is a naturally occurring contaminant of global concern due to its high toxicity presence in the atmosphere,” Lombard said.
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“Mercury” is Latin for hydrargyum, which means watery or liquid silver, and can be found in old thermometers or light bulbs. This highly toxic contaminant can be derived from natural sources such as volcanoes or oceans or from man-made activities like coal mining or waste deposits.
Lombard talked at length about wet versus dry deposition of mercury and how that impacts humans and other living organisms. “Within multiple waterways of the Northeastern U.S., which includes NH, fish and other aquatic species have shown elevated mercury levels, which could indicate bioaccumulation,” Lombard said.
“The FDA advises human consumption of only 12 ounces of low-mercury fish, and only six ounces of albacore tuna, especially in the state of NH where there are high levels of mercury found in fish. The consumption of these fish is a major route for human exposure to environmental mercury.”
According to Lombard, like many areas in New England, NH’s air quality is increasingly affected by large power plants in the Midwest, as well as urban areas in the south and along the East Coast.
“If we’re talking about dry deposition, mercury being deposited though the atmosphere, air circulation has everything to do with the levels of mercury being released into the air. If you release something into the air, it’s going to travel around the entire earth’s atmosphere and get deposited in multiple areas around the world,” Lombard said.
Within Lombard’s presentation, she mentioned the fact that there had been no active mercury wet deposition sites in the state of NH since 2005. Though a national network of wet deposition sites exists in Maine and other parts of New England, the AIRMAP program at the University of New Hampshire stepped up to help fill this gap.
“For almost three years I collected mercury wet depositions and reactive gaseous measurements at the Thompson Farm, a near-coastal rural site in Durham, NH,” Lombard said.
“When I ran these samples I had three trials to measure the average, and they all had a known value so that would have matched up with the measurements I obtained.”
The tests to compare the wet deposition to the dry deposition ran from July 21, 2006 to Aug. 30, 2009, during which time Lombard took six samples from 260 events.
“The reason for sampling wet versus dry depositions is to observe any trends that are discovered within my data. I found seasonal trends which portray high levels in wet deposition of mercury during the summer, and low levels during the winter.”
Lombard links the high levels during the summer months to active thunderstorms, and the low levels due to the absence of storms in the winter months.
“Thunderstorms are more abundant in the summer, which causes more air circulation that deposits mercury more frequently. You don’t see thunderstorms in the winter, which can account for the low levels of deposition,” Lombard said.
Students who attended the event couldn’t say enough about how well the facts were presented and how severe the issues of mercury deposits really are.
“I had no idea the fish we eat on a regular basis can contain such a deadly toxin. People should definitely be more aware of these mercury deposits, especially when the levels are so high in the state of NH,” KSC junior Joleen Ann said.
Bill Fleeger, an assistant professor of environmental studies, acknowledged the facts within the presentation and admired the importance of these issues.
“The importance is to reveal the information and the facts as well as the implications that follow,” Fleeger said.
“Mercury levels are so abundant in fish, it’s becoming way too dangerous to the human species,” Lombard said.
“The way it affects us is by eating seafood, and it’s most dangerous to pregnant women because it directly affects the brain of the fetus. It’s a neurotoxin, meaning it directly targets the central nervous system in a human being.”
“The research that Melissa brought forth has shown the problem we face with this deposition, but it’s on us to understand these issues and react to help save the uncertainty. “Truthfully, we hardly ever know the facts for sure,” Fleeger said.
Jon Carey can be contacted at email@example.com.