Posttest

For each question, select the one best choice

1. Which of the following statements about carbon tetrachloride (CCl₄) is INCORRECT?
   1. CCl₄ is a manufactured chemical.
   2. Its chemical instability results in an atmospheric half-life of 24-48 hours.
   3. CCl₄ is a clear, nonflammable, heavy liquid producing an odor similar to chloroform.
   4. Because of CCl₄‘s toxicity, consumer uses of this chemical have been discontinued in the United States.
2. All of the following statements about exposure sources are correct EXCEPT:
   1. U.S. public can be exposed to small amounts of CCl₄ through ambient air.
   2. Across the U.S., overall ambient air concentrations are slowly declining.
   3. Household cleaning products containing bleach can produce volatile organic compounds, including chloroform and carbon tetrachloride. Use of these common agents might, in part, explain elevated indoor CCl₄ concentrations.
   4. It is not permitted in products intended for home use; however, chemicals containing CCl₄ can still be purchased online.
3. Today, the U.S. general public is most commonly exposed to CCl₄ through
   1. Use of consumer products that contain CCl₄.
   2. Ingestion of contaminated food.
   3. CCl₄-contaminated ambient air and drinking water.
   4. All of the above.
4. Of the following occupations in the United States today, which is most likely to be at increased risk for exposure to CCl₄?
   1. Pesticide applicators.
   2. Dry cleaners.
   3. Hazardous waste workers.
   4. All of the above.
5. Which of the following statements about CCl₄ is NOT TRUE?
   1. Most inhaled CCl₄ is excreted unchanged in the urine.
   2. Metabolism of CCl₄ is required for toxicity.
   3. The CCl₃ radical is the key metabolite responsible for ultimate plasma membrane disruption and death of the cell.
   4. Alcoholic patients are far more susceptible to hepatotoxic effects of CCl₄ than are others.
6. All of the following statements are true EXCEPT
   1. Liquid CCl₄  is not easily absorbed through the human skin.
   2. Metabolism of CCl₄  is required for toxicity.
   3. Mixed function oxidase inducers can increase the toxicity of CCl₄.
   4. Unmetabolized CCl₄  is eliminated primarily in exhaled air.
7. Which of the following statements regarding U.S. guidelines and regulations for CCl₄ is FALSE?
   1. EPA classifies CCl₄ as a hazardous air pollutant.
   2. NIOSH has determined an air level of CCl₄ that might be immediately dangerous to life and health.
   3. Use of pesticide products containing CCl₄ is a major source of exposure in the general public in the United States today.
   4. EPA has set a maximum contaminant level for CCl₄ in drinking water.
8. Which of the following statements regarding signs and symptoms in patients exposed to a high dose of CCl₄ is INCORRECT?
   1. They will likely exhibit CNS and gastrointestinal effects.
   2. Symptoms that persist beyond 24 hours are most likely psychophysiologic in nature.
   3. Patients with acute and chronic exposures might exhibit some of the same symptoms.
   4. Hepatic and renal injury might manifest in 48 hours.
9. In general, patients over-exposed to CCl₄ by any route PREDOMINANTLY exhibit which of the following symptoms?
   1. Hepatomegaly.
   2. CNS depression.
   3. Nephritis.
   4. Pulmonary edema.
10. Which of the following is a direct biomarker of exposure to carbon tetrachloride?
    1. Kidney function tests.
    2. Blood CCl₄
    3. Liver function tests.
    4. None of the above.
11. Treatment for a patient with acute exposure to CCl₄ might include all of the following EXCEPT
    1. Administration of a free-radical scavenger such as N-acetylcysteine.
    2. Hyperbaric oxygen therapy.
    3. Irrigation of eyes and skin.
    4. Induced emesis for patients who have ingested CCl₄.
12. Patients should be advised on ways to avoid CCl₄ exposure and educated about possible health effects from exposure to CCl₄. Which of the following should be discussed with a patient exposed to CCl₄?
    1. The use of safer alternatives to products with CCl₄.
    2. The use of CCl₄-appropriate personal protective equipment (PPE), such as gloves, goggles, and respiratory protection.
    3. Increased area air ventilation when using products containing CCl₄.
    4. All of the above.