Environmental Toxicology (ADVS 5400/6400) Examination II Wednesday, March

Transcription

1 Name Environmental Toxicology (ADVS 5400/6400) Examination II Wednesday, March For questions 1-8, circle the letter corresponding to the correct statement(s). None, one or more of the selections may be correct. Incorrect responses will be deducted from your score (5 each) 1. The following are true statements about bioaccumulation: a. ecological magnification is directly proportional to partition coefficient b. bioaccumulation requires movement of mass through a food chain, from larger animals to smaller animals c. organic matter in soil decreases chance for bioaccumulation compared to clay d. not likely to occur with compounds that are rapidly degraded e. DDT more likely to bioaccumulate than parathion 2. The following statements are true for methylisocyanate (MIC): a. causes few persistent effects in exposed people b. food in the stomach increases t ½ in the body c. used as a starting material to produce strychnine d. because it is very chemically reactive, it is an indiscriminate toxin e. will often cause increased PCO 2 in exposed people 3. The following chemicals have "good warning properties:" a. hydrogen sulfide b. MIC c. cyanide d. formaldehyde e. benzene 4. The following are true of metals: a. thallium is odorless and tasteless, and has been used in murders b. As +5 is more prevalent but is less toxic than As +3 c. high amounts of Cd are found in the kidney mainly because of the presence of metallothionein d. nickel carbonyl is the least toxic form of nickel e. bauxite is a non-toxic form of aluminum 5. The following are true statements about inhaled toxicants: a. a major source of sulfur dioxide is volcanic stem vents b. aldehydes cause acetylcholine-mediated airway constriction c. PM 2.5 is associated with greater health risk than PM 10 d. CO has a much larger affinity for hemoglobin compared to oxygen e. PM 10 is of diverse chemical makeup 1

2 6. The following are correct disease: agent combinations: a. Shaver s disease: cadmium b. Hatter s disease: magnesium c. Painter s colic: iron d. Farmer s lung: ozone e. Itai Itai :mercury 7. The following are correct toxic incident : agent combinations: a. Minamata Bay: mercury b. Iraq: cadmium c. WWI gas: arsenic d. Bhopal: methylisocyanate e. Jonestown: cyanide 8. The following are correct symptom: agent combinations: a. Scleroderma: vinyl chloride b. Parkinsonism: manganese c. Alopecia: thallium d. Burton s line: lead e. Nickel itch : nickel 9. The toxicity of asbestos is thought to involve free radicals. a) Define free radicals; b) describe, in detail how free-radicals are involved in asbestos diseases; c) what are the major outcomes to free-radical damage to lipids and to DNA?; d) does this mechanism apply to all forms of asbestos? Explain. (10) 2

3 10. In certain parts of Silicon Valley, average intake of trichloroethylene (TCE) from contaminated groundwater is µg day. -1 If elimination has been calculated to be day, -1 a) what is the maximum amount of TCE that will theoretically accumulate in the body? b) when will the maximum amount of TCE in the body be achieved? c) if residents were given a safe organic resin to double the elimination rate, will this change a) and b), and the and if so, how? d) sketch (properly labeling each axis and curve) concentration-time curves to illustrate all your answers; e) before using the resin, do people eliminate a constant amount of TCE each day? Explain. (show all calculations!) (15) 3

4 11. In addition to disco, quadraphonic music systems, and polyester leisure suits, the 1970s saw a dietary supplement fad over the perceived benefits of certain types of fruit seeds. Many were sickened or died as a result of taking these "supplements." a) What is the common name for this bogus supplement? b) Identify the toxic agent from this compound; c) In detail describe it s precise mechanism of action; d) what are the symptoms of poisoning?; e) explain the treatment strategy and the mechanism of how the treatment works (15). 4

5 12. The pulmonary inflammatory response is one manifestation of PM 10 inhalation. In detail, describe: a) the important cellular and biochemical components and stepwise events in this pathogenesis; b) structural, functional and biochemical changes to the lung; c) explain how blood gas, compliance, respiration rate, and tidal volume will be affected as the disease progresses. (15) 13. Super bonus question: These classic LPs are made of a vinyl chloride-based polymer. Name each album, and identify their artists. 5