DABT study guide
DABT · Work through your exam, one topic at a time.
The Diplomate of the American Board of Toxicology (DABT) is a board certification for toxicologists - a credential earned by passing an examination administered by the American Board of Toxicology and maintained afterward according to the Board's requirements. It is aimed at scientists whose work involves evaluating hazard and risk: toxicologists in industry, contract research organizations, government agencies, academia, and consulting. The DABT study guide has 6 sections and about 1,580 words.
01General Principles of Toxicology
Toxicology studies the adverse effects of xenobiotics on living systems. Paracelsus framed the central idea: dose makes the poison.
278 words, about 1 min02Toxicokinetics and Biotransformation
Toxicokinetics describes absorption, distribution, metabolism, and excretion. Master first-order versus zero-order (saturated) kinetics, volume of distribution, clearance, half-life, AUC, bioavailability, two-compartment behavior, and enterohepatic cycling.
244 words, about 1 min03Target Organ and System Toxicity
Target organ toxicity reflects delivery, uptake, metabolic capacity, and repair. Liver: zone 3 (centrilobular) is rich in CYP enzymes and low in glutathione, so acetaminophen, carbon tetrachloride, and ethanol injure there; other agents produce zone 1 or bile duct injury.
263 words, about 1 min04Classes of Toxic Agents
Drugs: acetaminophen via NAPQI; NSAIDs through prostaglandin inhibition with GI and renal effects; opioids cause respiratory depression; chemotherapy includes anthracycline cardiotoxicity and cisplatin nephrotoxicity and ototoxicity. Industrial chemicals: solvents depress the CNS and injure liver; benzene damages marrow; PCBs and dioxin act through the aryl hydrocarbon receptor; formaldehyde causes irritation and is carcinogenic.
258 words, about 1 min05Risk Assessment, Epidemiology, and Regulatory Practice
Risk assessment comprises hazard identification, dose-response assessment, exposure assessment, and risk characterization. For noncancer endpoints, the reference dose (RfD) equals a point of departure (NOAEL or benchmark dose lower confidence limit) divided by uncertainty factors, typically 10 for animal-to-human, 10 for sensitive subpopulations, and 10 for database gaps, with modifying factors added when warranted.
260 words, about 1 min06Study Design, Data Interpretation, and Research Methodology
Valid toxicology depends on protocol quality: GLP compliance, OECD or ICH guidelines, defined species and strain, route, vehicle, dose selection from range-finding, a high dose that tests the maximum tolerated dose, a low dose near expected human exposure, concurrent controls, randomization, blinding, adequate sample size and power, and predetermined endpoints and statistics. In vitro and in silico methods such as Ames, micronucleus, comet, high-throughput screening, QSAR, and read-across support but rarely replace in vivo data.
277 words, about 1 min