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The light brownish color of smog often apparent in a major metropolitan area on a hot summer day is mainly due to
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Smog color is derived in part from suspended particulate matter. When smog is light brown, the color derives from nitrogen oxides. All of the other air pollutants listed are colorless. The answer is D.
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You are stuck in traffic in New York City in summer for 3 or 4 h and you begin to get a headache, a feeling of tightness in the temporal region, and an increased pulse rate. What is the antidote based on the most likely cause of these effects?
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The symptoms described are those of carbon monoxide inhalation. Oxygen is the antidote. The answer is D. Note atropine and pralidoxime are used in insecticide poisoning with acetylcholinesterase inhibitors, and fomepizole is used in methanol and ethylene glycol poisoning.
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A farm worker was accidentally in the field during the aerial spraying with parathion. He was brought to the emergency department. Which of the following will be used in the treatment of this patient?
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(E) Measures to reduce pulmonary edema
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Organophosphate poisoning is treated with the muscarinic receptor antagonist atropine and pralidoxime, which regenerates cholinesterase. The answer is B.
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A compound that is toxic to bone marrow cells in the early stages of development and that may also be leukemogenic is
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The aromatic hydrocarbon benzene is used as a solvent in industry. Long-term exposure is associated with increased risk of leukemia. The answer is A.
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A compound or group of compounds that damages the skin and whose use in manufacturing has largely been eliminated because of extensive persistence in the environment and bioaccumulation is
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(A) Aromatic hydrocarbons such as benzene
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(C) Phenoxyacetic acids such as 2,4-dichlorophenoxyacetic acid
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(D) Polychlorinated biphenyls (PCBs)
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(E) 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)
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The polychlorinated biphenyls (PCBs) are dermatotoxic drugs that persist in the environment and accumulate in living organisms. PCBs have been banned from manufacture in the United States since 1979. However, many electrical transformers still retain traces of them. The answer is D.
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An employee of a company engaged in clearing vegetation from county roadsides accidentally ingested a small quantity of an herbicidal solution that contained paraquat. Within 2 h, he was admitted to the emergency department of a nearby hospital. Which of the following best describes his probable signs and symptoms in the emergency department?
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(A) Diarrhea, vomiting, sweating, and profound skeletal muscle weakness
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(B) Dizziness, nausea, agitation, and hyperreflexia
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(C) Dyspnea, pulmonary dysfunction, and elevated body temperature
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(D) Gastrointestinal irritation with hematemesis and bloody stools
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(E) Hypotension, tachycardia, and respiratory impairment
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Paraquat is highly corrosive to the gastrointestinal tract. Oral ingestion of the herbicide leads to marked gastrointestinal irritation, hematemesis, and usually blood in the stools. Signs of pulmonary impairment do not appear for several days and are usually progressive, resulting in severe pulmonary fibrosis and, often, death. The answer is D.
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Chemical warfare agents that had been manufactured in the 1950s were being stored at a military installation. Several civilian workers at the facility began to feel unwell, with symptoms that included dyspnea, abdominal cramps, and diarrhea. They also had copious nasal and tracheobronchial secretions. Which type of toxic compound is most likely to be the cause of these effects?
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(A) Aliphatic hydrocarbons
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Highly potent organophosphate inhibitors of acetylcholinesterase (eg, sarin, tabun) have been developed for chemical warfare purposes. Their storage represents a potential toxicologic hazard. It is important to recognize the signs and symptoms of excess acetylcholine (DUMBBELSS; see Chapter 7), which include those described. The answer is D.
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The matching questions in this section consist of a list of lettered options followed by several numbered items. For each numbered item, select the ONE lettered option that is most closely associated with it. Each lettered option may be selected once, more than once, or not at all.
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Asthma is often exacerbated in patients exposed to this reducing agent when concentrations in the air are as low as 1–2 ppm. It is formed mainly from combustion of fossil fuels.
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Sulfur dioxide is a reducing agent that forms sulfurous acid on contact with moist surfaces. This is responsible for irritant effects on mucous membranes of the eye, the oropharyngeal cavity, and the respiratory tract. Nitrogen dioxide causes similar problems, but it is an oxidizing agent formed from fires and in silage on farms. The answer is L.
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The matching questions in this section consist of a list of lettered options followed by several numbered items. For each numbered item, select the ONE lettered option that is most closely associated with it. Each lettered option may be selected once, more than once, or not at all.
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Acute exposure to this aliphatic hydrocarbon solvent causes CNS depression; chronic exposure has led to impairment of memory and peripheral neuropathy.
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Three hydrocarbon solvents are listed: benzene, tetrachloroethylene, and toluene. Each can cause CNS effects such as headache, fatigue, and loss of appetite. However, benzene and toluene are aromatic hydrocarbons. The answer is M.
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The matching questions in this section consist of a list of lettered options followed by several numbered items. For each numbered item, select the ONE lettered option that is most closely associated with it. Each lettered option may be selected once, more than once, or not at all.
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This compound is a potential environmental hazard that is formed as a contaminating byproduct in the manufacture of herbicides. It causes acneiform lesions and may be carcinogenic.
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Dioxin is a contaminant formed in the manufacture of chlorophenoxy acid herbicides, including 2,4-dichlorophenoxyacetic acid and 2,4,5-trichlorophenoxyacetic acid. The answer is F.