Practice Questions Flashcards
A patient has blood work and other investigations done to identify the cause of their poisoning. The symptoms they present with do not match the expected toxidrome for the substance that caused their death. What is NOT a reason for a patient to present with almost none of the anticipated symptoms associated with the expected toxidrome for that drug class?
A. Additive effects
B. Brain damage
C. Conflicting symptoms due to polypharmacy
D. Delay in getting to the hospital means many symptoms have resolved
A. Additive effects might have an impact for trigger of symptoms. The other answers may suppress toxidrome symptoms. Additive effects may amplify effects. Additive effects may have the same symptoms but “worse”
Which type of assay typically relies on historical and/or periodic data with respect to positive controls rather than having them run with each test or assay?
A. In chemico
B. In silico
C. In vitro
D. In vivo
D
3R’s for reducing the amount of animal testing done when the effect is well known
Which of the following is used as a point of departure for calculating a human dose based on animal data?
A. ADI
B. BMD
C. RDA
D. TDI
B
OECD 413 describes how to conduct inhalation toxicity testing in rats. How are the test animals best divided with respect to bronchiolar lavage and histopathology?
A. They are randomly divided into four equal sized groups (e.g., female histology, male lavage)
B. They are randomly divided into two equal sized groups (i.e., lavage, histology)
C. A crossover study design is used so that each rat gets both just at different times
D. Each rat gets both as the lungs are divided during necropsy
D
The left lung is used for histopathology, the right lung is used for bronchoalveolar lavage fluid (BALF) analysis
Sodium hypochlorite (bleach) and hydrochloric acid solutions when combined cause the release of chlorine gas. According to the data in pubchem, chlorine gas has a human inhalation 5-minute LCLo of 550 ppm. Hydrochloric acid as a 5-minute LCLo of 3000 ppm. Sodium hypochlorite does not have a reported LCLo or LC50 for inhalation in humans or rodents but is still reported to cause lung irritation and even pulmonary oedema when its fumes are inhaled. In addition to being a chemical reaction, what else is this release of chlorine gas an example of?
A. Additive effects
B. Antagonism
C. Potentiation
D. Synergism
D
both sodium hypochlorite and hydrochloric acid are toxic but chlorine gas is more toxic than the two combined
Antibiotic drug levels are monitored and managed to try and avoid toxicity and antibiotic resistance. Drug levels for medications given in multiple doses are described as peaks and troughs and their shapes and sizes are important with respect to determining both effective and toxic doses. What number is NOT going to be found on a curve for a single dose that plots concentration against time?
A. AUC
B. Cmax
C.Tmax
D. Vmax
D
Cmax = concentration max
Tmax = time max
AUC = area under the curve
All are found for a single dose
Vmax is the saturation point; how quickly the ligand is broken down and eliminated by an enzyme somewhere else making it unavailable for the receptor in an active form
What type of product typically requires the least amount of testing and approval by regulators?
A. Additives to food
B. Biotechnological/biological products
C. Cosmetics
D. Drugs/pharmaceuticals
C
OECD 442B covers how to perform the local lymph node assay. This can be done using an ELISA or flow-cytometry to measure the number of proliferating cells. Proliferating cells are identifiable because they uptake what compound?
A. Adenosine
B. BrdU
C. Congo Red
D. DNA
B
Which of the following rates generally stays the same or even increases as people age from infancy to adulthood?
A. Breathing rate
B. Growth rate
C. Heart rate
D. Intestinal motility rate (i.e., hours it takes indigestible food (e.g., fiber) to pass through the intestines)
D
Limit tests are used to reduce the number of animals needed for acute toxicity testing. What is the smallest number of animals that have to die before a limit test is stopped and the main test is started?
A. 1
B. 2
C. 5
D. 10
A
Single animals are dosed in sequence at 48 h intervals. If animal dies directly, start the main test to find the LD50
Putting parrotfish on your plate can cause paresthesia as part of ciguatera poisoning. Parathesia is also associated with what kind of pesticide?
A. Paraquat and other quaternary ammonium herbicides
B. Parathion and other organophosphate insecticides
C. Permethrin and other pyrethroid insecticides
D. Piperonyl butoxide and other potentiating agents
C
pyrethroid insecticide, with sensation lasting up to 24 hours
Young children drink more than adults. But they are also more susceptible to water-based contaminants than adults. What chemical is known for causing blue baby syndrome due to its ability to cause methemoglobinemia?
A. Arsenic in drinking water
B. Benzene in drinking water
C. Chromium (hexavalent) in drinking water
D. Drinking water contaminated with nitrate
D
When nitrate becomes too high in drinking water, particularly well water contaminated with nitrogen rich fertilizers, it can be formed into nitrite by bacteria in the saliva and gut. Then that nitrite can turn hemoglobin into methemoglobin. Since methemoglobin is not nearly as effective as hemoglobin with respect to moving oxygen around to tissues, low oxygen levels causes the blood, and in severe cases particularly with pale babies, the whole body to turn blue
The 2022 DABT Exam Handbook recommends knowing how to select a relevant species for testing. Several species are recommended by the OECD for use in ecotoxicology testing. What do water fleas, earthworms, and minnows have in common?
A. They all have vertebrae
B. They are all invertebrates
C. They are all form a critical part at the top of their respective food chains
D. They all form a critical part near the base of their respective food chains
D
ICH M7 is not intended to be applied retrospectively to already approved products but is meant to be applied to products being developed. What would require reassessment of the potential risk of mutagenic impurities for an approved drug?
A. Altering the route of synthesis
B. Buying a raw material from a new supplier
C. Changing the manufacturing site
D. Demonstrating the purity, potency, and identity of the API remains the same
A
ICH M7 is not intended to be applied retrospectively to already approved products but is meant to be applied to products being developed. What would require reassessment of the potential risk of mutagenic impurities for an approved drug?
A. Altering the route of synthesis
B. Buying a raw material from a new supplier
C. Changing the manufacturing site
D. Demonstrating the purity, potency, and identity of the API remains the same
A
considering a new supplier would only be able to sell raw material such as API excipients etc. if the material is properly characterized and there are no mutagenic impurities and/or they are controlled below TTC (if any)
if it can be established that the new supplier also uses the same route of synthesis as of an already approved product, reassessment not required.
changing the manufacturing site would also not require reassessment as long as starting material, route of synthesis, reagents, solvents, or process conditions etc. have not changed significantly
What is true about placebos with respect to clinical trials?
A. They are always required in a study even to determine equivalence
B. They are always the only treatment given to a patient in that treatment arm
C. They never demonstrate any efficacy with respect to the patients receiving no treatment for any condition
D. They never include an active pharmaceutical ingredient (API)
D
Which of the following is a well-known hapten that causes occupationally acquired hypersensitivity?
A. Asbestos
B. Beryllium
C. Colchicine
D. Diphenhydramine
B
Which are the correct modes of action respectively for the following drugs that all interact with the opioid receptor; methadone, buprenorphine, and naloxone?
A. Antagonist, full agonist, partial agonist
B. Full agonist, partial agonist, antagonist
C. Partial agonist, full agonist, antagonist
D. Partial agonist, antagonist, full agonist
B
Methadone and buprenorphine are both used for medication-assisted treatment (MAT) to help reduce the harm associated with opioid addiction. Methadone acts as a full agonist of the opioid receptor. Buprenorphine acts as a partial agonist. Their use is tightly controlled. In contrast, naloxone is an antagonist of the opioid receptor and is used as an antidote to reverse the often fatal respiratory depression associated with opioid overdose. Because naloxone dose not cause the high associated with agonists of the mu opioid receptor it has been made much more widely available than methadone or buprenorphine.
What cardiac toxicity has been a major cause of pharmaceuticals being removed from the market?
A. QSAR
B. Q Slope
C. QT Prolongation
D. Quiescent cell cycle
C
Haber’s law can be used to describe how some gasses (e.g., hydrogen cyanide, hydrogen sulfide) can be rapidly incapacitating at relatively low concentrations while others take much higher concentrations to do the same because they are much less toxic. At the far end of this is nitrogen, which for mammals, can be considered biologically inert. What concentration does nitrogen have to reach in a room before it can rapidly incapacitat and eventually kill and otherwise healthy person?
C
Nitrogen makes up roughly 78% of normal air. Oxygen makes up around 20%. If the oxygen % falls below 10%, it can be deadly. Nitrogen gas causes death through a process called nitrogen asphyxiation” via the odorless, colorless, and tasteless gas. If the oxygen concentration is reduced by 10%, the condition is serious.
The EPA provides guidance on how to sample for toxicants in the environment and describes several different sampling tehcniques paying particular attention to their benefits, costs, and limitations. One of the more efficient methods when dealing with incomplete data about the source of contamination is the adaptive cluster sampling method. Which of the answers below shows this type of sampling?
A. scattered
B. clumpy and scattered
C. clumped
D. grid
B
Activating mutations in what gene(s) may result in early onset of cancer?
A. Apoptosis genes
B. DNA repair genes
C. Oncogenes
D. Tumor suppressor genes
C
OECD 405 covers in vivo eye irritation testing. It is only to be conducted if the chemical/mixture cannot be classified as either GHS category 1 or 2. What is true about this classification?
A. Category 1 is fully reversible within 21 days
B. Category 1 is not fully reversible within 21 days
C. Category 2 is not fully reversible withing 21 days
D. Category 3 is the most ever category for eye damage/irritation
B
OECD 405 describes how to conduct in vivo eye irritancy test. What is used for clinical obersvation and grading of eye reactions?
A. Ethidium bromide staining and a fluroescent microscope
B. Fluroscein staining and a slit lamp biomicroscope
C. Oil red o staining and a dissecting microscope
D. Ponceau S staining and a magnifying glass
B
Capsaicin and related compounds have been used to disperse crowds and protestors. The burning sensation they cause can continue for minutes to as much as an hour after people leave the scene. Per pubchem, Capsaicin has a logP of 3.6 while o-chlorobenzylidene malonitrile has a logP of 2.3. Given this information, what is true about the use of water to remove these irritants?
A. Creams and gels will work better than liquids at removing these compounds
B. Detergent and water solutions will work better than water at removing these compounds
C. Water will work better at removing capsaicin than o-chlorobenzylidene malontrile
D. water will work better than a water detergent solution at removing these compounds
B
A logP of 3 means 1,000 molecules in oil to 1 in water. A logP of 2 means 100 molecules in oil to 1 in water. The difference between 99% and 99.9%
Different agencies (e.g, OSHA, NIOSH, ECHA) provide OELs for chemicals. In these cases, what does OEL stand for?
A. Observed Effect Level
B. Oncological Equivalent Level
C. Occupational Exposure Limit
D. Organismal Effect Limit
C
Thalidomide was brought back as a drug after being initially removed from the market due to its teratogenic effects (e.g., phocomelia). What is true about the steps that were taken before it was allowed back into clinical trials?
A. All patients were required to have a negative pregnancy test before receiving thalidomide
B. blood donation was forbidden while taking the medication and for a month after treatment stopped
C. Condoms weren’t required for men receiving thalidomide as long as they had had a vasectomy
D. druglevels had to be monitored to avoid birth defects
B
Naloxone is an opioid receptor antagonist that can reverse potentially fatal respiratory depression. Unlike with benzodiazepines where the withdrawal can be fatal, opioid withdrawal is far less dangerous. So why is it that toxicologists tend to recommend giving just enough nalaxone to restore breathing but not necessarily enough to overcome sedation?
A. Aspiration is a greater risk if they’re fully awake
B. Beds are always plentiful so there’s no advantage to waking the up sooner
C. Constipation is a likely effect if an opioid is removed from too many receptors
D. Dangerous behavior can result in polypharmacy is present and sedation is removed suddenly
D
ICH M3(R2) refers to limit doses for a number of different types of studies. What is the main goal of limit doses?
A. To avoid large fold-differences between doses given to test animals
B. To avoid testing animals with doses that would not add value to predictig clinical safety
C. To avoid testing any animals
D. To identify the lower limist of a toxic effect (e.g., LOAEL, NOAEL)
B
An injectable general anesthetic is being developed for both short-term and long-term use. What type of normally required study can be modified and partially replaced with data from a similar compound due to technical difficulties?
A. Ames mutagenicity study
B. Blood protein (e.g., albumin) binding study
C. Chronic toxicity study at a MTD
D. DART study where mating behavior is being evaluated
D
Which of the following is an uncoupler of oxidative phosphorylation that has been used for weight loss but that can cause potentially fatal hyperthermia?
A. 2,4-D (2,4-dichlorophenoxyacetic acid)
B. DNP (2,4-dinitrophenol)
C. Ortho-fluorofentanyl (N-(2-fluorophenyl)-N-[1=(2-phenylethyl)piperidin-4-yl])propenamide)
D. PCB-105 (2,3,3’,4,4’-pentachlorobiphenyl)
B
A case study where over 100 people were sickened when they ate salad due to the unintentional additon of a toxicant. The patients sufferend dry-mouth, fever, and in some cases, even became delirious. What was the likely cause?
A. .Anticholinergic effects due to a Datura species (e.g., Jimsonweed) being present in the field and getting harvested along with the spinach
B. Beets high in nitrate caused methemoglobinemia and related symptoms
C. Cholinergic effects due to the crops being harvested too soon after the fields were sprayed with a cholinesterase inhibiting insecticide (e.g., chlorpyrifos)
D. Diuretic effects due to a Chimaphila species (e.g., Pipsissewa) was being present in the field and getting harvested along with the spinach
A
A patient’s urine contains significant amounts of albumin. What has likely happened to their kidneys?
A. dehydration
B. glomerulus has been damaged
C. nothing this is perfectly normal
D. proximal tubule was been damaged
B
A rodent NOAEL dose was 1.1 mg/kg and an uncertainty factor of 100 was applied to get a human dose. What was that dose?
A. 1.1 ug/kg
B. 11 ug/kg
C. 110 ug/kg
D. 110 g/kg
B
The EPA 1998 Guidelines for Ecological Risk Assessment describes cascading effects. What would be a secondary effect?
A. Herbicide evaporates and travels to neighboring field killing crops
B. Herbicide runs off field and kills off pond plants
C. Herbicide kills off pond plants and ducks lose feeding habitat
D. Herbicide gets in applicators eyes and causes serious irritation
C
What carcinogenic mineral used to be the main ingredient in one kind of fake snow?
A. asbestos
B. boric acid
C. chlorpyrifos
D. diatomaceous earth
A
Alternative methods are being explored to study developmental toxicity without having to dose pregnant animals and follow them through development. What is the simplest terms of biological organization as well as being the most limited in terms of endpoints of the models listed below?
A. African clawed frog (Xenopus leavis larvae)
B. Bud limb Mus musculus (Mouse) embryonic mesenchymal cells
C. Caenorhabditis elegans (Nematode) larvae
D. Danio rerio (Zebrafish) embryos
B
A patient starts taking many times the recommended amount of their medication. This drug has more than one effect but is type of analgesic. The patient goes to the hospital and reports their symptoms. What of the following drug and symptom combinations are most likely to be matched?
A. Aspirin and acute kidney failure and bloody urine
B. Bleeding and metabolic acidosis while taking acetaminophen (aka paracetamol)
C. Codeine and respiratory depression and sleepiness
D. Diethylene glycol and icterus (i.e., jaundice) and high liver enzyme levels (e.g., ALT, AST)
C
What ocular condition has been associated with acute exposure to naphthalene?
Cataract
What type of radiation has the highest linear energy transfer (LET)?
Alpha particles
The US FDA has been asked by some to remove from the market sunscreens containing the active ingredient octocrylene. What is the suspected carcinogen that it may contain?
Benzophenone
Benzophenone is formed when octocrylene breaks down. Octocrylene now makes up a significant percentage of sunscreens in the market as it was used to replace octinoxate after the Hawaii ban.
Which nonclinical species has a choclea of similar size, structure and auditory sensitivity as the human cochlea and has been used in auditory toxicology experiments?
Chincilla
What marine bio toxin is responsible for amnesic shellfish poisoning?
Domoic acid
What is the toxic substance found in betel nuts?
Arecoline
