Reference no: EM133204825
Assignment: Tuna for Lunch?
First read the "mercury in fish case study" file found in Canvas for this unit. While reading you will come across questions, pause to consider them, most of them you will answer for this assignment.
After you read the entire case study, answer the questions below.
Part I
1. What is in some fish and shellfish that has caused the EPA and FDA to issue the restriction?
2. Why is there a restriction for pregnant women and young children, but not the rest of the population?
3. Do pregnant women have to avoid all fish? Explain your answer.
4. Should Amanda have avoided the pan-seared tuna for lunch?
Part II
1. What human actions lead to increased mercury levels in the environment?
2. How does the mercury end up in fish?
3. Where in the United States are mercury wet deposition levels highest? What do you think explains this pattern?
4. The EPA criterion for human health is 0.3 ug/g. Which fish species have average mercury concentrations that exceed the EPA limits?
5. The concern level for piscivorous (fish-eating) mammals is 0.1 Hg ug/g. Which fish species have average mercury concentrations that exceed this limit? Why is the mercury level for piscivorous mammals lower than the level for human health?
6. Should you be concerned about mercury toxicity if you catch and eat a largemouth bass in a local lake? Why or why not?
7. In which samples were mercury concentrations the highest (fish, streams, or sediment)? Why do you think this is?BE SURE to pay close attention to the units when finding this answer!
Final Activity (based on all parts of the case study and external research)
1. Imagine you are Tara. Write a short summary to your friend Amanda explaining what you have learned about mercury. Be sure to convey the aspects of your learning that will be most useful to Amanda. Basically this is a summary of what you learned.
2. Find two other examples of compounds that biomagnify. Explain how each compound and/or toxin enters the biosphere and what impacts it has on living organisms in general and humans in particular. Remember your previous assignments which you considered reliable sources, be sure you consult reliable sources for this answer and include the sources in your answer.
3. Distinguish between bioaccumulation and biomagnification.