The sample exam questions provided are derived from the 2004 and 2005 Recertification examinations.  Not all question categories are represented, largely because those exams contained more than 50% of Type B questions, which are no longer being used on certification examinations.  Happy practiciing, and good luck!

PART C SAMPLE QUESTIONS

1. A threshold limit value-time weighted average for a chemical represents
A) an airborne concentration of a chemical that can never be exceeded
B) an airborne concentration of a chemical that is believed to cause no adverse health effect to a worker exposed for 8 hours a day, 40 hours a week
C) an airborne concentration of a chemical that cannot be exceeded for longer than 15 minutes a day
D) a value for an acceptable airborne concentration of a chemical established by the Occupational Safety and Health Administration
E) an airborne concentration which cannot be measured using available technology

2. The reference dose (RfD) is generally determined by applying which of the following default procedures?
A) an uncertainty factor of 100 is applied to the NOAEL in chronic animal studies
B) a risk factor of 1000 is applied to the NOAEL in chronic animal studies
C) a risk factor of 10,000 is applied to the NOAEL in subchronic animal studies
D) an uncertainty factor between 10,000 and 1 million is applied to the NOEL from chronic animal studies
E) multiplying the NOAEL from chronic animal studies by 100

3. Which of the following concerning the use of the "benchmark dose" in risk assessment is NOT correct?
A) can use the full range of doses and responses studied
B) allows use of data obtained from experiments where a clear "no observed adverse effect level" (NOAEL) has been attained
C) may be defined as the lower confidence limit on the 10% effective dose
D) is primarily used for analyses of carcinogenicity data and has limited utility for analyses of developmental and reproduction studies that generate quantal data
E) is not limited to the values of the administered doses

4. Administration by oral gavage of a test compound that is highly metabolized by the liver versus subcutaneous injection will most likely result in
A) less parent compound present in the systemic circulation
B) more local irritation at the site of administration caused by the compound
C) lower levels of metabolites in the systemic circulation
D) more systemic toxicity
E) less systemic toxicity

5. Which of the following is the most significant contributor to air pollution by mass in suburban areas?
A) manufacturing
B) transportation
C) space heaters
D) electric power generation
E) waste disposal

6. Methylation
A) typically increases the water solubility of xenobiotics
B) is a major pathway of xenobiotic metabolism
C) requires S-adenosylmethionine (SAM)
D) requires acetyl coenzyme A
E) requires taurine

7. From 1973 to 1977, the average annual incidence rate of lung cancer in Connecticut was 45.9 per 100,000. The average annual prevalence was 23.0 per 100,000. From these values, what is the average duration of survival after being diagnosed with lung cancer?
A) 2 years
B) 6 months
C) 1 year
D) 8 years
E) 4 years

8. Of the more than 40 cytochrome P450 isozymes, which 6 account for the majority of xenobiotic metabolism in humans?
A) CYP1E1, CYP2B1, CYP2B19, CYP2F1, CYP3A7, CYP4A6
B) CYP1A1, CYP2A6, CYP2B6, CYP2D6, CYP2F2, CYP4B2
C) CYP1B2, CYP2C6, CYP2F2, CYP3A2, CYP3A4, CYP4A2
D) CYP1A2, CYP2C9, CYP2C19, CYP2D6, CYP2E1, CYP3A4
E) CYP1A1, CYP2C8, CYP2F2, CYP3A7, CYP4A2, CYP4A6

9. Which of the following conditions represents a manifestation of moderate chronic fluoride toxicity?
A) osteomalacia
B) osteosclerosis
C) osteopetrosis
D) osteopenia
E) osteolysis

10. Intoxication from consumption of wild cherry or apricot pits would best be treated by
A) hyperbaric oxygen
B) artificial respiration
C) inhalation of amyl nitrite
D) intravenous sodium nitrite and sodium thiosulfate
E) oral sodium nitrate

11. Drug X is available as a 2.5% solution for intravenous administration. The desired dosage of this drug is 5 mg/kg. What volume of drug should be injected if the patient weighs 50 kg?
A) 0.2 ml
B) 1.0 ml
C) 2.0 ml
D) 10 ml
E) 20 ml

12. The phrase that best defines "toxicodynamics" is the
A) linkage between exposure and dose
B) linkage between dose and response
C) dynamic nature of toxic effects among various species
D) dose range between desired biological effects and adverse health effects
E) loss of dynamic hearing range due to a toxic exposure

13. Which of the following was banned under the Delaney clause of the Food Additive Amendment of 1958?
A) butylated hydroxytoluene
B) sulfamethazine
C) cyclamate
D) phytoestrogens
E) aflatoxin

14. Which of the following is NOT a characteristic of active transport?
A) blocked by saxitoxin
B) movement against a concentration gradient
C) exhibits a transport maximum
D) energy dependent
E) selectivity

15. Which of the following is NOT an initiating event in carcinogenesis?
A) DNA adduct formation
B) DNA strand breakage
C) mutation of proto-oncogenes
D) oxidative damage of DNA
E) mitogenesis

16. Which of the following does NOT inhibit electron transport?
A) rotenone
B) succinate
C) antimycin-A
D) formate
E) azide

17. Reabsorption of toxicants does NOT occur through
A) entero-hepatic recirculation
B) glomerular filtration
C) diffusion
D) active transport
E) carriers for physiologic oxyanions

18. Which of the following does NOT uncouple oxidative phosphorylation?
A) pentachlorophenol
B) dinitrophenol
C) aconitase
D) salicylate
E) gramacidin

19. Which of the following is NOT true regarding peroxisome proliferators?
A) they are a structurally diverse group of chemicals
B) they cause marked induction of lipid metabolizing enzymes
C) they often are non-genotoxic hepatocarcinogens in rodents
D) they induce hepatic CYP1A which is indicative of peroxisome proliferation
E) they operate via the peroxisome proliferator activated receptor

20. Permissible Exposure Limits are
A) promulgated by the Occupational Safety and Health Administration and have the force of law
B) identical to and interchangeable with Short Term Exposure Limits
C) authorized under the Toxic Substances Control Act
D) promulgated by the Environmental Protection Agency
E) are directly adopted from the American Conference of Governmental Industrial Hygienists Threshold Limit Value list

21. Which of the following has NOT been linked to human lung cancer?
A) arsenic
B) nickel
C) silica
D) chromium
E) antimony

PART C ANSWERS

1. B
2. A
3. D
4. A
5. B
6. C
7. B
8. D
9. B
10. D
11. D
12. B
13. C
14. A
15. E
16. B
17. B
18. C
19. D
20. A
21. E