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Mercury and Water There is no other pollutant [other than mercury] out there that has anywhere near this high a percentage of the U.S. population with exposure levels above the government’s health advisory levels. Not lead, not arsenic, nothing. Yesterday’s water essay excluded the story with mercury and water partially as an oversight and partially because the mercury and water story is so big. Mercury has spread out into the atmosphere, soils, lakes, rivers and into the oceans where it gains strength and toxicity through the process of methylation. Radioactivity tends, with the passing of many years, to lower in toxicity but mercury runs up the hill to more toxic levels with the help of fish, mammals and bacteria. Mercury bio-accumulates and under goes bio-magnification. The term bioaccumulation refers to the net accumulation over time of metals within an organism from both biotic (other organisms) and abiotic (soil, air, and water) sources. The term bio-magnification refers to the progressive build up of some heavy metals (and some other persistent substances) by successive trophic levels – meaning that it relates to the concentration ratio in a tissue of a predator organism as compared to that in its prey. Top predatory fish, like a tuna, can easily have sequestered in its flesh methylmercury levels that are a million times higher than the water it swam in. In the next ten years we will pollute the world with approximately another sixty to ninety thousand tons of mercury after already adding over 600 thousand tons during the past century. The real problem with mercury, even the mercury we excrete from our bodies that we ourselves are absorbing from our dental fillings, the air we breathe, water we drink and the food we eat, is that it does not leave the environment. It keeps bioaccumulating building in concentration each year. Fish around the world are showing dangerous levels of mercury threatening one of mankind’s basic supplies of protein with lakes, rivers and even the deep ocean badly contaminated with mercury. States issued warnings for mercury and other pollutants in 2003 for nearly 850,000 miles of U.S. rivers – a 65% increase over 2002 – and 14 million acres of lakes. The warning level is the highest ever reported by the EPA. It is partly a result of states taking a more aggressive role in monitoring for mercury, according to environmental officials. The problem is getting worse and each year the earth comes closer to reaching a saturation point where the entire situation will seriously deteriorate. The huge tonnage of mercury put into the environment each day is adding to an already critical situation. Considering that mercury is an accumulative poison with delayed effects or a lag time measured in years, we can see that humanity has created a time bomb that is ticking while even more mercury is added. Ignorance of mercury’s toxicity has led us as individuals and as a society into dangerous waters and collectively it threatens us with premature death and years of chronic illness. Current average precipitation mercury levels are on the order of 2-4 times greater than pre-industrial levels based on information on the increases in mercury deposition rates (Swain et al., 1992; Expert Panel on Mercury Atmospheric Processes, 1994). Source. 1997 U.S. Environmental Protection Agency Report to Congress Volume 3 We have just reached the crisis level on mercury. Now, we’re finding it in our food, our water, our soil, our babies, everywhere. All of these increases that involve the sea are mirrored on land. Drinking water is a good place to see the extent of the disaster in the making. The EPA reports that mercury levels in tap drinking water in the United States ranges anywhere between 0.3 to 25 ng/L (NJDEPE 1993) but some wells were tested up to and exceeding 2000 ng/L (Dooley 1992). In general Mercury measured in surface fresh water around the world ranged from 0.04 to 74 ng/L in lakes and 1-7 ng/L in rivers and streams (NJDEPE 1993). These are all old numbers and it is anyone’s guess as to current concentrations in water supplies. Mercury from air and soil provides the main source of mercury to water bodies and fish. Mercury is very slowly removed from soil, and long after anthropogenic emissions are reduced, soil and water concentrations can be expected to remain elevated. Source. 1997 U.S. Environmental Protection Agency Report to Congress Volume 3 Though it is critical to the future of humanity to understand the changes in mercury concentration levels in the deep sea there is a scarcity of information on the subject. The highest number that has been quoted for increases of mercury concentrations in the marine environment is 3.5 to 4.8% per year, [i] though 1.5 percent increase per year is generally the number that yields some level of acceptance. By considering the current global mercury budget and estimates of pre-industrial mercury fluxes, Mason et al. (1994) estimate that total emissions have increased by a factor of 4.5 since pre-industrial times, which has subsequently increased the oceanic reservoirs by a factor of 3. Rolfus and Fitzgerald (1995) made the obvious conclusion that increases in the deposition of mercury that result from increases in anthropogenic emissions will result in enhanced food chain bioaccumulation and higher concentrations of mercury in marine fish. Estuaries and coastal regions obviously are more highly affected by anthropogenic mercury sources. Current average precipitation mercury levels are on the order of 2-4 times greater than pre-industrial levels based on information on the increases in mercury deposition rates (Swain et al., 1992; Expert Panel on Mercury Atmospheric Processes, 1994). Anthropogenic emissions are currently thought to account for between 40-75% of the total annual input to the global atmosphere (Expert Panel on Mercury Atmospheric 3-2 Processes, 1994; Hovart et al., 1993b). Source. 1997 U.S. Environmental Protection Agency Report to Congress Volume 3 The amount released into the air, water and soil has increased greatly since pre-industrial times because of industrial air emissions, water discharges and the combustion of mercury-containing fuels. [ii] Most of this released mercury ends up in soils and waterways, where it is methylated by microbes to form methylmercury, which then accumulates in the tissues of predatory fish and mammals. Mercury levels in the environment have been rising but the exact numbers are not clear. A 1996 EPA report to Congress said that mercury levels in the environment had increased 2-5 fold over the last century and 1.5% per year since 1970. The deep ocean is little understood due to sparse observations but mercury levels appear to be rising there though it is understood that concentrations of mercury in the deep sea are more from natural sources than man made sources. The most reliable indication of mercury levels in the sea are the changes being noticed in the large fish that live the longest and also by sea birds. In such birds mercury levels have increased from a range of 0.4 to 1.8 parts per million before 1860 to 6 to 25 parts per million between 1970 and 1980 which represents an increase of 1400 %. [iii] Researchers have found mercury levels in the whales of the belugas went up four-fold during the 1990s. Mercury levels are three to four times higher in beluga whales in the Western Arctic compared to the small, white whales farther east according to Eric Braekevelt of the Department of Fisheries and Oceans in Winnipeg Canada. [iv] He stated that, “There’s some speculation that it might be coming from the Mackenzie River,” As one of the largest river systems in the world, the Mackenzie drains much of Canada, and there is significant industrial development in parts of the watershed. In Australia researchers studying dolphins have noted that inshore dolphins had mercury levels on average 14 times greater than dolphins living offshore in the Southern Ocean. They are reporting that record levels of mercury have been found in dozens of dead dolphins recovered from South Australia’s Spencer and St Vincent gulfs. Toxicology research on 114 bottlenose dolphins by Adelaide University student Nicole Butterfield has found the mercury level of one dolphin to be four times higher than Australia’s previous worst case. The dolphin contained 1900 micrograms of mercury per gram and was retrieved near Point Riley, on the Spencer Gulf and just south of the industrial town of Port Pirie. An adult female found dead in 1998 recorded the highest mercury level for a bottlenose dolphin at 465 mcg per gram. In Japan it has been reported that in some cases the levels of mercury in dolphin and whale meat sneakily sold there are 1,600 times the allowed quantities in meat for human consumption. According to Dr. Tetsuya Endo, at the University of Hokkaido, two of the 26 whale liver samples examined contained over 1970 micrograms of mercury per gram of liver. That is nearly 5000 times the Japanese government’s limit for mercury contamination (0.4 micrograms per gram) or an incredible 20,000 times the USEPA limit of 0.1 microgram per gram. More average concentrations of mercury in whale and dolphin livers were 370 micrograms per gram, 900 times the government limit. Average levels in kidneys and lungs were also high, about 100 times the limit. Endo’s team has shown that rats suffered acute kidney poisoning after a single mouthful of the most highly contaminated liver. While levels were lower in muscle, Dr. Endo said in a draft paper accepted for publication in The Science of the Total Environment, “Acute intoxication could result from a single ingestion.” [v] All of this tells us there is mercury in the water, not just the ocean but in the glass you drink possibly, certainly in all the rivers, lakes and streams. It is the toxin in the environment that we must be most concerned about for it is the most toxic. Mercury is building up all around us and we have to protect ourselves and our loved ones from it as much as possible. It is not enough just to avoid the mercury using dentists nor the thimerosal using doctors. We got to take it out of our water. To filter out everything but the mercury, the most toxic substance, would be more than foolish. Mercury Toxicity Reference[i] United States Environmental Protection Agency, Office of Water, June 2003, The National Listing of Fish and Wildlife Advisories: Summary of 2002 Data, EPA-823-F-00-20,www.epa.gov/waterscience/fish/ ; & U.S. EPA, Office of Water, Mercury Update: Impact on Fish Advisories-Fact Sheet, http://www.epa.gov/ost/fish/mercury.html; & New England Governors and Eastern Canadian Premiers Environment Committee Mercury Action Plan, June 1998. [ii] Pilgrim W, Poissant L, Trip L. The Northeast States and Eastern Canadian Provinces mercury study: a framework for action. Summary of the Canadian chapter. Sci Total Environ 2000;261: 177-84 [iii] Finch, Bill. Raines, Ben. Mercury myth’ persists despite facts. Mobile Register. 12/23/01 [iv][v] http://www.newscientist.com/news/news.jsp?id=ns99992362 |
Mercury and Water
After polluting the world with over 600,000 tons of mercury in the last century, it's estimated we'll add 60,000 to 90,000 more in the next 10 years...
