Acute – looks at the immediate effect of a chemical to an organism. LD50 is an example.
Allergic Response – due to sensitization of the immune system to a particular chemical resulting in specific antibodies or sensitized cells. Response does not occur at initial exposure.
Biotransformation – the process whereby a substance is changed from one chemical to another by a chemical reaction in the body.
Chronic – looks at the long-term effects of a chemical to an organism. Examples include reproduction and development.
Dose – total amount of chemical to which an organism is exposed.
Doseage – determined based on characteristic of the animal such as weight. Used to normalize overall dose.
ED50 – the dose which produces an effect in 50% of the population tested.
First-Pass effect – process whereby a chemical taken orally must first pass through the liver, thereby increasing its chances of becoming metabolized and eliminated.
Half-life – the time it takes for a chemical/drug concentration to be decreased by 50%. A chemical with a half life of 5 days will be at 50% of its original concentration at the end of 5 days.
Hydrophilicity – water-loving and less likely to be absorbed into lipids (fats). Hates lipids.
Idiosyncratic Response – due to a genetic pre-disposition of an individual to overreact to a chemical
Lipophilicity – lipid-loving and more likely to be absorbed into lipids (fats). Hates water.
LOEL – the lowest level (dose/concentration) which produces an effect.
LOAEL – the lowest level (dose/concentration) which produces an adverse effect.
LD50 – the dose which produces lethality in 50% of the population tested.
NOEL – the highest level (dose/concentration) at which no effect occurs.
NOAEL – the highest level (dose/concentration) at which no adverse effect occurs.
Phase I – mechanism designed to