As tale of Teresa Casal Ed.S. FCE LTER

Objectives-  Learn about the chemistry, the sources, cycling and health effects of mercury.  Trace Hg as it travels through the Everglades.  Identify strategies to reduce the risk of Hg ingestion.  Create a public service announcement to alert the public of Hg toxicity.

Once upon a time… “On a planet, not called Mercury, ‘fluid silver’ was used by Aristotle for religious rituals (it facilitated a smooth transition into the afterlife) while Hippocrates prescribed it as a medicine (before malpractice became a practice) Roman vanity had it applied as a cosmetic (guaranteed to have life altering results) and the Medievalists ‘bet their lives’ on it as an effective cure for syphilis

as time would tell… … in the Pre - industrial era many lined their coffins while using it to extract gold and other metals … and today, “quicksilver” used in alkaline batteries has left its mark, ever ready to find its way into our lives… …will we live happily ever after??? …will we live happily ever after???

Mercury in Wonderland No wonder they called him the “Mad Hatter” Lewis Carroll’s character suffered from delirium and hallucinations typical of prolonged contact to the mercury used in the fur, felt and hat industry

From alchemy to chemistry Mercury is…  a natural element  odorless  liquid metal  shiny  silver-white  atomic number 80

On the flip side… On the flip side… It is very persistent It accumulates in the environment And it is definitely very toxic

Oh… I get it! That’s why it’s called PBT! A persistent, bioaccumulative and toxic pollutant. What’s the catch?

Manufacturing activities Mining Wastewater into waterways Dental material waste Fuel combustion Waste incineration The cycle begins with man

Through the environment Mercury filled rainfall Is absorbed by sulfate-reducing bacteria Undergoes chemical changes (Hg to methyl mercury (MeHg+). Concentrates as it moves up the food chain

And returns to man   Through contaminated foods   By exposure to mercury spills   From inhalation of Hg-containing particles   For newborns through contaminated mother's blood and breast milk

What is the bottom line?  May cause cancer  Damages the stomach and large intestine  Permanently damages the brain and kidneys  Permanently harms unborn children  Can cause lung damage, increased blood pressure and heart rate

Use the right bait…  Follow fish consumption advisories  Consume no more than one meal a week of the species listed in the advisory  Stay within 0.3 mg methyl mercury/kg in fish tissue

to reel in the best catch  Use small pan fish, perch, rock bass, and crappie (if less than 9 inches)  Avoid older predatory fish (ie. walleye, bass, and pike)  Nursing mothers, pregnant women, and children under the age of 15 should NOT eat any swordfish or shark.

In a nut shell…

Now it is your turn to… Research the amount of Hg in different types of fish. Research the amount of Hg in different types of fish. Create a public service announcement to alert the public of Hg toxicity. Create a public service announcement to alert the public of Hg toxicity.

References   EPA Persistent Bioaccumulative and Toxic Chemical Program at   Mercury\Fact Sheet Methyl mercury - Ambient Human Health Water Quality Criteria - U_S_ EPA.htm   Florida International University, Research in Review; Florida’s Mercury Menace Issue, Fall & Winter, 1997   Mercury Physical and Chemical Properties at Hg/key.html Hg/key.html