Toxicology Test #2 Name_Elissa Ness__ Given: 4/29/2020 Due: 5/6/2020 Using any publically available resources, not including your classmates, answer each of the following questions to the best of your...

Toxicology Test #2

Name_Elissa Ness__

Given: 4/29/2020 Due: 5/6/2020

Using any publically available resources, not including your classmates, answer each of the following questions to the best of your ability. Put all answers in your own words and do not quote outside sources, though you should cite outside sources when necessary. Answer the questions in the order they are asked. Uploaded responses will only be accepted in text editable form (word document or similar), not pdf.

1) Metal Speciation

A) Farmer Bob illegally uses lead shot to hunt ducks which results in lead emissions to Farmer Bob’s favorite duck pond. Assume the lead is oxidized from Pb⁰to Pb⁺², which results in a Pb⁺²concentration of 0.002 mg Pb⁺²/L in the pond and that no solid phases are present. Calculate the speciation of the Pb⁺²using V-MINTEQ in the surface water. What Pb species is present at the highest concentration in the water (2 points)? What Pb species is the most toxic in this solution chemistry (3 points) (provide a reference)? You will need to do some research to determine the concentration of the different ligands in the pond water. Include table with the Pb speciation distribution (not the entire speciation table) and the solution chemistry you decided to use.

Calculated speciation pf Pb

Pb species present at highest conc

PB species that is most toxic

B) Now assume the Pb⁺²diffuses into the sediments at the bottom of the duck pond and calculate the lead speciation in this reducing environment. Assume that SO₄
^-2in the surface water is chemically reduced and that no solid phases are present. Once again, you will need to do some research to determine what is the concentration and makeup of the sediment pore water. What Pb species is most significant in the sediment water (2 points)? What Pb species is the most toxic in this solution chemistry (3 points) (provide a reference)? Include the Pb speciation distribution in your answer.

Pb speciation calculated

Pb that is most signifigant

Pb species that is most toxic

2) List the enzyme(s) that would metabolize the compounds below (1 point each). Draw or describe the metabolites (2 points each).

A) Dieldrin

B) Bifenthrin

C) Malathion

D) Phenyl glycidyl ether

E) Trinitrotoluene

3) Bob, the owner of Chinchillas and Chihuahuas, uses fenvalerate to delouse his stock of chinchillas and chihuahuas. Being a frugal businessman, he pours the remaining 7 gallons of 5 g/L fenvalerate down the storm drain when he is done. This drain empties directly into Lake Bemidji.

A) At equilibrium what percentage of the fenvalerate ends up in the fish in Lake Bemidji, the air above lake Bemidji, and the water of Lake Bemidji? You will have to make many assumptions to answer this question. State your assumptions and justify why you made the assumptions you did. Answers will only be accepted in Excel Spreadsheet form with each calculation labeled. If you have questions, please ask. (10 points)

Fenvalerate

Log K_ow=6.2

Log K_aw=-7.5

B) What factors are not considered in this calculation that would make the result you calculated more realistic? (5 points)

4) For each of the following compounds or family of compounds identify a biomarker for that compound and explain the qualities of that biomarker that make it useful. Do not list the original material or metabolites of the original material. Provide a reference for your rational (2 points each).

A) PAHs

B) Alkylphenols (e.g. nonylphenol)

C) Lead

D) atrazine

D) Bisphenol A

5) In “Widespread occurrence of intersex in black basses from US rivers 1995-2004 (aquatic toxicology 95 (2009) 60-70) Hincket alreport on the occurrence of intersex in fish from across the United State. Use this paper, available on D2L, to answer the following questions: (3 points each)

A) Generally speaking, where was intersex occurrence higher and where was intersex occurrence lower?

B) How did age influence the occurrence of intersex?

C) What was the relationship between vitellogenin concentration in the black bass and the occurrence of intersex in the black bass?

D) Were the authors able to determine the gender of individual black bass? Why or why not?

E) Was there one single factor that lead to the observed intersex?

F) The authors recommend that future work investigate the influence of a variety of factors on the occurrence of intersex. What are these?

6)One take home message from this class is available in question #7 on thecourse evaluation page, what is it? Please fill out the course evaluation while you are there. (5