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Mercury
by Tyler Zimmerman
Physical Geology
Spring 2013
  
 

Mercury Poisoning From Eating Tuna
 


 

          How often do you eat tuna? Are you even concerned with the amount of tuna you consume? People are  often baffled when they find out the dangers of eating tuna. So what are some of the possible risks of eating too much tuna?

         Tremors
  Changes in vision or hearing
  Insomnia
 Weakness
 Memory problems
 Headache
 Nausea
 Vomiting
 
Diarrhea
 Increases in blood pressure or heart rate
 Eye irritation
  Irritability
 Shyness
 Nervousness
 Breathing problems
 Painful mouth
 Abdominal pain
  Fever and/or chills

         Acrodynia caused by chronic or long-term exposure to mercury. The symptoms for this include itching, swelling, flushing, pink colored palms, excessive perspiration, rashes irritability, fretfulness, sleeplessness, joint pain and weakness.

               Some children may experience trouble learning in school

       If you hadn't noticed, these are all the symptoms of mercury poisoning. Mercury is the 80th element on the periodic table. It has 80 protons and has the chemical symbol Hg. Its atomic mass is 200.59 atomic mass units, melts at -30.87 degrees Celsius, and boils at 356.58. Elemental mercury is a silver-white, heavy, mobile, liquid metal at room temperature. It is the only metal on the periodic table that is found as a liquid at room temperature. Mercury simply is not for human consumption. Mercury is considered a heavy metal like zinc, iron, and lead; but our bodies only make use of zinc and iron. The human body uses zinc, zinc is an essential trace element for humans, animals and plants. It is vital for many biological functions and plays a crucial role in more than 300 enzymes in the human body. Iron is also useful, iron is needed for a number of highly complex processes that continuously take place on a molecular level and that are indispensable to human life. So what about mercury in the human body? Mercury has two fates - bile or blood. It can get incorporated in bile and excreted back into the intestines where  it can be either reabsorbed or excreted in your feces. The other fate for mercury is the blood stream. Once in the blood stream mercury readily travels to the kidneys or the brain. In the kidneys it can get filtered and excreted in the urine or stored. The kidneys contain a protein called metallothionein that binds mercury and stores it in a nontoxic form. As long as the dosage of mercury does not overwhelm the system the kidneys will do a good job of synthesizing metallothionein and binding mercury as needed. If it finds a way to the brain it gets transferred across the blood brain barrier and stored. The storage option is the one that leads to mercury toxicity causing damage to the brain or kidneys.

 

Tuna is not an evil food however. It's actually quite amazing considering the nutrition: it's an important part of a healthy diet because they contain good quality protein and essential nutrients including omega 3 fatty acids, and are low in saturated fats. So you can work it into your diet, but how much?



 

If you weigh:

Don't eat more than one can every:

 

 

White Albacore

Chunk Light

20 lbs

10 weeks

3 weeks

30 lbs

6 weeks

2 weeks

40 lbs

5 weeks

11 days

50 lbs

4 weeks

9 days

60 lbs

3 weeks

7 days

70 lbs

3 weeks

6 days

80 lbs

2 weeks

6 days

90 lbs

2 weeks

5 days

100 lbs

2 weeks

5 days

110 lbs

12 days

4 days

120 lbs

11 days

4 days

130 lbs

10 days

4 days

140 lbs

10 days

3 days

150+ lbs

9 days

3 days

 

 

 

Source: Food and Drug Administration test results for mercury and fish, and the Environmental Protection Agency's determination of safe levels of mercury.

 

 


 

 

Now you must wonder, why did I choose to attack tuna? Tuna is the second most consumed fish in the United States behind shrimp. And of all the fish that are contaminated, it ranks pretty high. Isn't it weird we choose to most commonly eat a highly contaminated fish? 
 


 

It's important people know what they are putting into their bodies. Just because it's on the shelf, doesn't mean it's completely safe.

 

Works Cited

http://knowitallhealth.com/2009/01/12/mercury-rising-are-you-eating-too-much-tuna/ 

http://www.nelsonsnaturalworld.com/en-us/uk/our-brands/spatone/iron-essentials/role-of-iron-in-the-body/

http://www.zinc.org/info/zinc_essential_for_human_health

http://www.bodybuilding.com/fun/mroussell5.htm 

http://acc6.its.brooklyn.cuny.edu/~scintech/mercury/Whatis_mercury.htm

http://www.nrdc.org/health/effects/mercury/tuna.asp