Mercury in the Everglades

Mercury in the Everglades
Mercury in the Everglades

Everglades Background Information:

Established in 1947 on 1.4 million acres in southwest Florida
Sunny, Semi-Tropical Swamp Setting. Experiences near daily downpours
Mercury?s Effect on the Everglades:

A small amount of mercury is found in the crust of the earth. This is not the problem. The anthropogenic mercury is the problem.
The mercury that is growing dangerously in size is known as methylmercury. It is an organic substance that still baffles scientists who are trying to work out its life cycle. So far, what they know is that methylmercury forms when inorganic mercury combines with organic matter that is dissolved in water. This reaction favors conditions that are extremely warm, where there is plenty of sunlight, and where the right kind of bacteria is present (mainly sulfate reducing bacteria). The Everglades, unfortunately, because of its large amount of sunlight and the near daily downpours provides ideal environment for forming methylmercury.


Mercury settlement:
The majority of mercury sett;es into the surface sediment where the amount of mercury was2.5 times more than the deep sediment. This of course leads to an even greater chance of the mercury getting recycled into the food chain rather than decomposing.


Biomagnefication:
Methylmercury becomes deadly to the environment through the process of biomagnefication. To achieve biomagnefication, the mercury must be consumed by microorganisms nd work its way up the food chain increasing in concentration as it enters larger and larger organisms. Methylmercury enters the food chain of the Everglades through plankton, which eats the methyl mercury loaded bacteria. The plankton is then consumed by slightly larger invertebrate animals. These invertebrates soon become dinner for much larger invertebrates such as snails, shrimp, and then fish. These in turn are then consumed by larger fish who become eaten by land dwelling animals such as raccoons, birds, alligators, panthers, and finally humans. With each step in the food chain, the concentrations of methyl mercury increases by ten. Thus it is the accumulation of the methylmercury, as a result of the biomagnefication, that is deadly.


Effects of the influx of Methylmercury:
1. Death of three panthers 2. Declining number of wading bird, otter and mink populations 3. Toxic levels of mercury found in alligators 4. In humans, it can lead to brain damage, blindness, learning disabilities, and death. It can also be passed very easily from mother to child during pregnancy. In one extreme case, mercury poisoning led to the death of a Dartmouth College scientist who got a drop of a mercury compound on her glove. She was dead within ten months. 5. Can also cause infertility in birds.


Economic Effects of Mercury Poisoning:
Not only do the numerous bans around the state hurt the sport of fishing, it has hurt those who make a living off the fishing and the state which collects licensing and recreation fees. Thus the mercury affects all aspects of the world.


Global Impact of Rising Mercury Levels:
To begin with high levels of mercury is a problem in places other than Florida. Mercury advisories have been issued worldwide such as in Scandinavia, Canada, and the majority of Europe and Asia. In Florida, three water bodies have been placed on the consumption ban list and thirty-six have a limited fish consumption advisory. To be deemed a no consumption water body; the inhabiting species must have an average level of mercury above 1.5ppm. To be put on the limited consumption list they must have .5ppm mercury.

Possible Sources of Mercury:
Incinerators and agricultural processes surrounding the Everglades

Atmospheric Circulation: Global circulation causes mercury to travel thousands of miles from as far away as Europe and Asia and is ?scrubbed? out of the atmosphere by rainstorms over the Everglades which conveniently lies in the path of trade winds. One study shows that 95% of the mercury arrives in the Everglades via the atmosphere.

Hydrological changes resulting from the Central and South Florida Flood Control Project


Conclusion:
Rising mercury levels in the Everglades is just one of the problems that we need to deal with in order to protect our Everglades. However, it is not an issue that we can procrastinate on or fight over. Mercury levels are rising and our time is running out. We need to act before it is too late.

Mercury in the Everglades 7.8 of 10 on the basis of 3308 Review.