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Mercury Contamination of Land and Water Organisms. Mimi Templeton, Samara Hutt, Grace McKeon, and Logan Cox Woodstock Union High School . Conclusions
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Mercury Contamination of Land and Water Organisms Mimi Templeton, Samara Hutt, Grace McKeon, and Logan CoxWoodstock Union High School Conclusions We conducted this research to determine how mercury affects terrestrial and aquatic organisms. Our hypothesis stated that if we test terrestrial and aquatic organisms then we would find that water organisms have more mercury than land organisms because methylation occurs in sediments under the water. The graphs that we made suggest many different conclusions. For example, the graph comparing the earthworm and the aquatic worm shows that the earthworm has more mercury than the aquatic worm. The earthworm has 254.2 ppb of mercury in wet weight, and the aquatic worm only has 34.9 ppb, which is a significant difference. Part of the reason the earthworm has such a high amount of mercury is because there were many high outliers in the earthworms that were sampled. This might lead one to believe that land organisms have more mercury than water organisms. However, the other graphs suggest that aquatic organisms contain more mercury. The graph comparing the spider and the aquatic beetle shows that the spider has 50.3 ppb of mercury, while the aquatic beetle has 112.4 ppb of mercury. The last graph shows less of a difference between land and water organisms; the ant has 18.3 ppb of mercury while the snail has only .3 ppb more than the ant, it contains 18.6 ppb. Some sources of error might be the fact that we sampled 11 earthworms and 8 spiders, and we only sampled one of the rest of the organisms. The data we collected also came from different sites, which could affect the amount of mercury because of different amounts of wet deposition and runoff. The data also came from different years, which could change the amount of mercury as well. We could improve the research not only by sampling more of each organism, but by sampling even more organisms, and organisms that came from the same site and the same year. Also, if we could get organisms from each trophiclevel, we would have a wider range of data and it would be more reliable. We were missing producers and quaternary consumers. In the end, the results were inconclusive and our hypothesis was neither supported nor disproved. Introduction Mercury is a toxin, it is a natural element that is distributed by wet and dry deposition, it is distributed and moved around by coal burning, rain, and runoff. when it enters the body it starts to accumulate. After a while it will end up shutting down major organs such as your liver or kidneys eventually killing you. The organ that mercury effects highly and is famously known from “The Mad Hatter” is your brain. In the 19th century mercuric nitrate was known for the making of felt which was used to make hats; when exposed to this by wearing the hats the wearers experienced mental confusion, emotional disturbances and muscular weaknesses. In nature there is a process called methylation.This is when mercury becomes methylmercury, it happens under water in sediments where there is very little or no oxygen (anaerobic conditions). Fish or other aquatic organisms eat the bacteria which has producedthe methylmercuryand then it gets passed up to the next level of organisms.. This process is called biomagnification, and this is the way we most commonly obtain mercury. Land insects get mercury by eating other living things as well. However, they aren’t exposed to as much methylmercurybecause they are not in water where methylmercury is created. We decided to research the way mercury is passed up through these levels inboth land and water organisms. Results Hypothesis If we test terrestrial and aquatic organisms then we would find that water organisms have more mercury than land organisms because methylation occurs in sediments under the water. Literature Cited "What You Need to Know about Mercury in Fish and Shellfish." Home. EPA, n.d. Web. 19 Fears, Darryl. "Study Links Warmer Water Temperatures to Greater Levels of Mercury in Fish." Washington Post. The Washington Post, 15 Oct. 2013. Web. 18 Dec. 2013Fears, Darryl. "Study: Warm Water, More Mercury Found in Fish." The Bulletin. Washington Post, 14 Oct. 2013. Web. 18 Dec. 2013. <http://www.bendbulletin.com/csp/mediapool/sites/BendBulletin/News/story.csp?cid=1286328> "Isopod." Isopod. N.p., n.d. Web. 20 Dec. 2013. <http://www.fcps.edu/islandcreekes/ecology/isopod.htm>. Materials and Methods First we had to gather all of our information from data that was collectedby the University of Maine and Dartmouth College. All of the samples were collected by students and were sent to the colleges to be processed. The samples that we ended up choosing were a snail, earthworm, ant, aquatic beetle, aquatic worm, and a spider. After we gatheredall of their data, we put all the information into excel. Then we made it into a bar graph. We realized that it was hard to compare so we made them into 3 different graphs. Acknowledgments Thank you to the National Park Service and to the students who collected the data. We would also like to thank the University of Maine and Dartmouth College for processing the data.