Study Suggestions and Exam Notes
• Be able to define Toxicology, Environmental Toxicology, Ecotoxicology
• Be able to describe Paracelcus’contribution to toxicology (mainly, dose makes the
• What was the impact of Silent Spring?
• What were the toxicants behind the effects in the ecological disasters in Minamata,
Chernobyl, Bhopal? What was a common thread behind these disasters (poor safety
• Why did the researchers not originally determine the cause of Minamata disease? How
was the cause ultimately confirmed?
• Definitions of Toxin, Toxicant, Poison, Xenobiotic, LD50, LC50, LOAEL, NOAEL,
Potency, Efficacy, Acute, Chronic, Sub-chronic, Placebo, Nocebo, Systemic Toxicity
• What are standard endpoints in acute and chronic toxicity testing?
• Pros and Cons of Acute Toxicity testing?
• Make sure you can follow the logic and units in the math examples
• Shortcomings of LD50 approach?
• Difference between effective and toxic dose; between threshold and non-threshold
• Explain two instances where low dose may be beneficial
• Give an example of a placebo effect? A nocebo effect?
• How can rate of elimination impact toxicity?
• Describe the three potential types of chemical interaction Lecture 3
• What are the four elements of disposition?
• What are three key routes of exposure/ sites of absorption for humans with respect to
• Are compounds more likely to be absorbed in GI tract when they are ionized or
non-ionized? What controls degree of ionization?
• How does size influence absorption from GI?
• Define: Bioaccessibility, Bioavailability, paracellular, intracellular
• How does particle size influence particle deposition into the lungs?
• What are the two major layers of the skin? What is the rate limiting barrier for dermal
• What are 5 factors influencing dermal absorption?
• What is the K ? How is it related to polarity/lipophilicity?
• Explain the first-pass effect. Describe some pathways that bypass this effect
• What are the four primary sites for toxicant storage in the body?
• What is the main objective of biotransformation of organic contaminants? Describe Phase
I, Phase II
• Two reasons why infants may be more susceptible to toxicants?
• Can biotransformation increase toxicity?
• Describe the major and minor routes of excretion. Lecture 4
• What effects, at the individual level, are we most interested in in ecotoxicology?
• Define EC ,50C , 25at kind of effects might be measured?
• Why study earthworms?
• What makes a good test organism?
• What are some of the key requirements in the earthworm acute toxicity test? Limitations
of earthworm testing?
• Why is it important for the performing laboratory to regularly assess the LC50 of a
• Why do an acute test? Why do a chronic test? What are some advantages and benefits of
• Define: systemic pesticide, biomarker