Introduction to Toxicology Flashcards
What is toxicology?
The study of adverse effects of chemical or physical agents on living systems
What makes a substance a toxin vs a toxicant?
Toxin: A poisonous substance produced by living cells
Toxicant: A man made chemical introduced into the environment that produces toxic effects on living cells.
How do you indicate if a activity/intervention is an example of descriptive, mechanistic or regulatory toxicology?
Descriptive: Area of focus in toxicology concerned with determining the toxic responses to agents.
Mechanistic: Area of focus in toxicology concerned with why or how toxic agents provoke a toxic response.
Regulatory: Area of focus in toxicology concerned with assessing the risk of toxic substances and determining how that risk is best managed.
What is the difference between local vs system toxic response?
Local: happens at the sight of exposure
Systemic: happens distant to to sight of exposure
What is the difference between immediate vs delayed toxic response?
Immediate: response within seconds to hours
Delayed: response within days to years
What is the difference between reversible vs irreversible toxic response?
Reversible: effect abates after stopping exposure
Irreversible: effect persists after stopping exposure
What are the 3 phases of toxic response?
Exposure: inhalation, ingestion, dermal absorption
Disposition: primarily deposits in adipose tissue, bone, soft tissue, secretory structures
Toxicodynamics: cellular responses
What are the 3 means by which toxic responses can be mitigated?
Prevent/reduce exposure: flush area with water
Enhance elimination from body: filtering blood and dialysis to increase excretion
Block/repair cellular effects: naxolone
What is the lowest observable adverse effect level (LOAEL)?
The lowest dose upon administration that provokes an adverse effect on the test oganism.
What is the no observable adverse effect level (NOAEL)?
The highest dose upon administration that fails to provoke any observable adverse effect in the test organism.
Very important parameter that is used to determine first does in man of a new drug.
Done on multiple species beforehand and scaled up to man.
