Circle the one best answer, unless otherwise instructed. Point values are given following the individual questions.

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1 Biology 5868 Ecotoxicology Name KEY Final Exam December 21, 2004 Circle the one best answer, unless otherwise instructed. Point values are given following the individual questions. 1. Which of the following would be most likely associated with DNA adducts? (1) a. PCBs b. TCCD c. DDT d. PAHs 2. In humans, exposure to dioxin would most likely be manifested by which symptom in the shortterm? (1) a. no effect b. skin rash c. liver damage d. death 3. Lacking any other data, the most important single characteristic to predict toxicity of a chemical is: (1) a. pk a b. molecular weight c. log K ow d. log K oc 4. Necropsy of animals poisoned by an unknown toxicant showed a buildup of glucuronateconjugated organics in the blood plasma. This suggests: (1) a. the toxicant inhibited Phase I and Phase II detoxification pathways b. the toxicant inhibited Phase I, but not Phase II detoxification pathways c. the toxicant did not affect detoxification, but inhibited biotransformation pathways d. the toxicant did not affect detoxification, but inhibited elimination pathway 5. Toxicity tests showed that chemical X had very low initial toxicity. However, the test organisms showed liver lesions that were traceable to a metabolite of chemical X. The phenomenon most likely responsible for this toxicity is: (1) a. potentiation b. synergism c. antagonism d. activation 6. A toxicant that operated primarily by creating reactive oxygen species might stimulate the following set of cellular markers: (1) a. DNA adducts, photolyase induction, increased apoptosis rate b. catalase induction, lipid peroxides, glutathione reductase activity c. mixed function oxidase induction, acetylcholinesterase inhibition d. elevated T lymphocytes, alkaline phosphatase induction, metallothionene induction 1

2 7. Given this toxicant structure, which of the following biomarkers would be the most likely? (1) O 2 N O P OCH 2 CH 3 a. superoxide dismutase and catalase induction b. acetylcholinesterase inhibition c. EROD activation d. formation of DNA adducts 8. Tributyltin is most often associated with (1) a. abnormal keratin deposition resulting in crossed bills in seabirds b. & & pairings in gulls c. tumor formation in fish d. imposex in gastropods 9. Why is methyl mercury more toxic than elemental mercury? (1) organic moiety facilitates entry into cells 10. What are the three most likely causes of amphibian malformations (3) 1. UV radiation 2. retinoid mimics 3. parasites 11. Which of the following is not an acceptable biomarker? (1) a. behavioral modification b. cytochrome P450 induction c. increase in lymphocyte concentration d. all are acceptable 12. An efficient biomonitor: (1) a. accurately predicts toxicant effects b. operates in a variety of affected taxa c. operates for a variety of different toxins d. provides sufficient data at a reasonable cost 13. What are the two forms of biomonitoring? (2) 1. exposure 2. effect 14. In the Simple Comparative Model of response to multiple stressors, the total effect of two stressors would be: (1) a. the product of the individual stresses b. a fraction of the individual stresses c. the sum of the individual stresses d. none of the above O OCH 2 CH 3 2

3 15. For contaminant Z, draw two simple graphs with dose increasing on the X axis and response increasing on the Y axis (NO NEED FOR NUMBERS). Label one graph A and use it to show a classic Dose vs. Response relationship constructed with raw, untransformed data. Label the other graph B and use it to show a representative Dose vs. Response relationship constructed with raw data that were transformed via application of a metameter. (2) A typical answer is shown in the text; page 179, figure 9.2. Graph A will be a sigmoid plot and graph B will be a straight line. 16. A. What is the dependent (response) variable for acute toxicity tests? (1) death (survival is also acceptable) B. List three dependent (response) variables for sub lethal toxicity tests? (3) 1. e.g. behavior, reproduction, growth, physiology, developmental endpoints, etc Which one of the following examples properly presents a very fundamental principle of Ecotoxicology? (1) a. NOEC > MATC < LOEC b. LOEC < MATC < NOEC c. NOEC < MATC < LOEC d. MATC > LOEC < NOEC 18. One bioassay summary below is correct and the other contains three errors. Circle the incorrect summary and identify the three points of error and briefly explain why they are erroneous. (3) The median lethal concentration of Boom Insecticide to mysid shrimp was reported as LD 25 = 50 ng/l (ppb). The median lethal dose of Boom Insecticide to the bobwhite quail was reported as LD 50 = 100 mg/kg (ppm). The first bullet should be circled. Errors:1) Notation should be LC, not LD (concentration is the variable) 2) the subscript should be 50, not 25, since it is a median lethal endpoint 3) the unit ng/l equate to ppt, not ppb 19. Which single property of sediments has the most influence on the bioavailability of organic contaminants? (1) a. particle Size b. ph c. sulfate content d. total organic carbon content 3

4 20. Which one of the following properties of organic contaminants has the most influence on their bioavailability in sediments? (1) a. polarity b. octanol/water partition coefficient c. fluorescence capacity d. number of alkyl groups 21. Give one compelling reason why some ecotoxicologists feel that the principles of Epidemiology should be applied to studying populations exposed to contaminants. (1) e.g. Statistically derived endpoints do not necessarily reflect biological significance e.g. Statistically based predictions of safety thresholds do not address long term viability 22. Epidemiology is not a universal solution to ecotoxicological problems. A.B. Hill s nine Logical Rules attempt to ameliorate what key shortcoming of Epidemiology? (1) Epidemiology is based on inferential, not proven, cause and effect relationships 23. A. Given the following long term study results, calculate the Incidence Rate of contaminantrelated reductions in the feather density of black capped chickadees: (1) Observed number of affected individuals = 1016 Days of exposure to contaminant = new individuals per day. B. What would the Prevalence of the adverse affects to black capped chickadees be for a oneyear period of exposure to the contaminant? (1) individuals per year. (NOTE 1.27 also accepted) 24. Which one of the following concepts/principles is not fundamental to Metapopulation theory? (1) a. source sink hypothesis b. a patchy environment c. intrinsic rate of increase d. mobility of individuals 25. Recall from Dr. Niemi s guest lecture that not all wetlands were treated with a mosquito control agent. Given that fact, and the fact that birds are not directly affected by methoprene or BTI, which one of the following aspects of Metapopulation Dynamics would not be an effective approach to study birds that utilize treated wetland habitats? (1) a. effect at a distance hypothesis b. propagule rain effect c. rescue effect d. keystone habitat 26. Which one of the following variables is the fundamental unit of a Life Table? (1) a. q x b. d x c. l x d. m x 27. You are recording data that you will ultimately analyze and interpret with Demographics and Life Tables. The loading factor for each experimental unit in your study was 50 individual test organisms. What is the proper way to record the result for an experimental unit that has 40 test organisms surviving? (1) proportion; i.e. 40/50 = 0.8 4

5 28. Calculate the missing values for the Age Specific Number of Individuals Dying (d x ) in the following table of demographic data. No calculation is necessary for the cell with 0, the cell with 12 and the cell with \\\\. (6) Age Class (x) l x * 100 d x \\\\ 29. Calculate the Age Specific Death Rate (q x ) for Age Classes 2, 4 and 6 in the table above. Please convert the three l x * 100 values back to their original l x values before completing these calculations. (3) Age Class NOTE partial credit of two points given if Age Class l x values were not converted back. Age Class Life Tables that focus on l x and m x are useful to discern what population parameter? (1) a. migration distance b. nutritional demand c. proportion of males d. reproduction rate 31. Resistance to the herbicide glyphosate is controlled by a set of minor genes. Resistance to the herbicide glufosinate is controlled by a few major genes. Which herbicide is associated with Vertical resistance and which herbicide is associated with Horizontal resistance? (2) glufosinate = vertical glyphosate = horizontal 32. Prepare a simple bar chart of three communities (X axis), each of which comprised of three species, to illustrate the following aspects of species diversity: (3) Community One Is a very diverse community that has high levels of both species richness and evenness. Community Two Is less diverse than Community One in terms of species evenness. Community Three Is less diverse than both Community One and Two in terms of species richness. Sp 1 Sp 2 Sp Sp Sp Sp Sp Sp or community 1 community 2 community 3 Sp 1 Sp 2 Sp 3 5

6 33. Recall that the macroinvertebrate community was adversely affected by repeated exposures to a pyrethroid insecticide in a mesocosm study; e.g. multiple spray drift and runoff event simulations were used. If only one spray drift simulation was used, without any runoff events, how would you rank the following community qualities regarding their influence on macroinvertebrate community response? (3) 1 Elasticity 2 Resilience 1 Inertia Ranks: 1 = influential, 2 = Not Influential 34. An undisturbed habitat supporting mature communities responded with significant adverse effects to a contaminant. The post spill conditions now favor species which: (1) a. are considered r strategists b. mature quickly c. produce many offspring d. all of the above 35. When a contract laboratory has to dilute a high concentration field sample, which two of the following analytical limits are affected? (2) a. the Practical Quantitation Limit (PQL) b. the Instrument Detection Limit (IDL) c. the Method Detection Limit (MDL) d. the Limit of Linearity (LOL) 36. Match the following Lab Analyses to the Intents listed in the table: (3) a) Lab Control Standards, b) Method Blanks, c) Matrix Spikes Intents Assess Method Performance Assess Sample Property Interference Detect Instrument Contamination Lab Analyses A C B 37. An aqueous photolysis study has been submitted by a chemical company associated with a contaminated site within the St. Louis River estuary. The chemical being studied is known to have minimal photo activity. The water characterization data verify that the study was conducted with St. Louis River water because the levels of dissolved organics were high. What type of aqueous photolysis study should have been conducted by the chemical company? Give two reasons to support your answer. (3) indirect photolysis because: 1) chemical has minimal photo activity 2) dissolved organics are high 38. The half life of compound Z was found to be 14 days in a field conducted soil dissipation study that was found to successfully meet EPA registration requirements. After being approved for use and sale, an accidental spill of compound Z resulted in a soil concentration of 460 mg/kg on the day of the spill event. What would the expected concentration of compound Z be in samples of spill site soils 28 days after the spill event? (1) 115 mg/kg. 6

7 39. Hydrolysis of a chemical can be simply represented by RX + HOH ROH + HX. List the two study condition parameters that most significantly influence this reaction. (1) 1. ph 2. temperature ( light is acceptable in place of either of these) 40. This graph was obtained from a fish bioassay that was conducted with dilution water that had a hardness of 100 mg/l CaCO 3. Add two more straight lines to this graph that keep the intercept at 0 0, but have their slopes altered so as to represent what the results would be like in harder and softer dilution water. Be sure to label the two new lines to distinguish the one that goes with the harder dilution water from the one that goes with the softer dilution water. (4) Influence of Water Hardness Number Dead 6 Number of Dead Cd Concentration in ppb The line for softer dilution water will have a steeper slope; harder dilution water will have a less steep slope 41. When Mass Balance is the objective of an environmental fate study, which one of the following attributes of the parent compound is essential to attaining that objective? (1) a. its availability as a sodium salt for use in the study b. its availability as radio labeled material for use in the study c. its availability as a solid for use in the study d. its availability in mass quantity 42. You have thoroughly and correctly defined the Null and Alternative hypotheses for your research. You decide to test your hypotheses with statistical procedures that recognize the level of α to be 0.20 instead of the traditional level of Are you now more vulnerable to committing a Type I or Type II error? (1) Type I Error 7

8 43. Assuming that your Null hypothesis for question 28 was the traditional there are no differences in responses among treatments, would your study conclusions tend to overstate or understate the treatment effects with the level of α set at 0.20? (1) a. overstate b. understate Use the following data for the next two questions to calculate the inventory change of chemical X in the sediment of an active shipping slip for Additions Estimated mass of X in the 1999 Losses slip at the close of grams of X grams of X 10 grams of X from from runoff biodegradation 50 grams of X from bilge water 120 grams of X from natural currents and prop wash 44. Inventory change of X = 30 grams (be sure to indicate + or ). (1) 45. Estimate the mass of X in the sediment of the shipping slip at the close of (1) grams of X. 46. The vast majority of PAHs are not water soluble, and they have a strong affinity for particulate matter. Given these properties, the distribution of PAHs in aquatic ecosystems is primarily attributable to which one of the following transport processes? (1) a. non diffusive b. osmosis c. diffusive d. calcium mediated advective 47. Calculate the Toxic Unit (TU) values of X and Y to complete the final column of the following table: (2) Chemical Incipient LC 50 TU value Concentration in Mixture TU value in Mixture X 50 ng/l 1 25 ng/l 0.5 Y 200 ng/l ng/l The mixture of chemicals X and Y defined in the table above was used to conduct toxicity tests with Daphnia, rainbow trout and bluegill sunfish. The results of these tests are as follows: (3) Test Organism Result Daphnia 75 % mortality Rainbow Trout 50 % mortality Bluegill Sunfish 30 % mortality A. Draw an Isobologram for the mixture of chemicals X and Y that displays three features: 1) a line representing Additivity 2) a point labeled SYN for Synergism 3) a point labeled ANT for Antagonism 8

9 B. Print the test organism name next to the feature of the Isobolgram that properly defines its response to the mixture of chemicals X and Y. Newman & Unger Figure 9.5 (p. 184) is the basis for the correct answer. Daphnia will be associated with Synergism, Rainbow Trout will be associated with Additivity, and Bluegill will be associated with Antagonism. 49. Which one of the following sample manipulations is not part of the TIE process? (1) a. adjust ph b. aeration c. addition of EDTA d. heating to 120 degrees C e. filtration 50. Good Laboratory Practices apply directly to which one of the following pairs of Federal Acts? (1) a. CWA and NEPA b. FIFRA and TSCA c. CAA and SDWA d. RCRA and CERCLA 51. Which one of the following Federal Acts addresses hazardous wastes at active facilities from cradle to grave? (1) a. CERCLA b. FIFRA c. TSCA d. None of the above 52. Regarding quality assurance (QA) and quality control (QC), which of the following entities: a. Quality Assurance Officer b. President & CEO c. Technician is primarily responsible for: (3) A. QA b B. QC c C. QA and QC a 53. Vitellogenin in the blood plasma of male fish would suggest exposure to: (1) a. dioxin b. PCBs c. ethinyl estradiol d. any of the above 9

10 54. Define narcosis (1) e.g. chemical toxicity resulting from non specific membrane effects 55. Developing organisms are usually considered more susceptible to toxicant effects. List two reasons that this is the case. (2) 1,2. e.g. immature immune system, immature detoxification system, high level of transcriptional activity, high toxicant intake in proportion to mass 56. According to Dr. Schoff s Rule of Acronyms, which of the following is not a proper acronym? (1) a. NEPA b. TSCA c. CERCLA d. FIFRA 57. QSAR is based on the premise that: (1) a. molecules with similar structures will have similar functions b. similarity between atomic components of molecules can be quantified c. binding sites on target molecules have limited by quantifiable flexibility d. all of the above 58. Draw a graph showing cell growth on the Y axis and toxicant concentration on the X axis. Draw one line showing a situation with a threshold response and a second line showing a hormetic response. (1) hormesis cell growth threshold toxicant concentration 59. As endocrine disruptor screening assays take place at higher levels of biological organization, they become: (1) a. more reliable b. more expensive c. more reproducible d. all of the above 60. An Ecological Risk Assessment: (1) a. is the ultimate source used by Risk Managers in decision making processes b. is a document covering a predetermined set of toxicity evaluations and uncertainty evaluations. c. does not contain information about costs of remediation efforts d. none of the above 10

11 61. In the Ecological Risk Assessment process, data gathering occurs in which step(s) (1) a. Problem formulation b. Problem Formulation and Analysis c. Analysis and Risk Characterization d. Problem Formulation and Risk Characterization e. Problem Formulation, Analysis, and Risk Characterization 62. Referring to your Risk Assessment project: A. What was the source of the greatest uncertainty in your choice of driver metals? (2) acceptable answers include (but are not limited to): cross species comparisons lack of information about organisms at different trophic levels lack of information about presence of organisms at test site B. Pick two alternative organisms (not used in your exercise) that could be used as receptors. Give rationale/justification for expending resources on each. (2) Acceptable answers include (but are not limited to): insect (sp) oligochete (sp) amphibian (sp). 63. Fill in the missing item in the following Major Rule of Ecotoxicology (0) No Food No Drinks No Snoose. No Smoking 11