INTRO TO TOXICOLOGY Flashcards
study of how toxicants cause adverse effects on living organisms.
toxicology
science dealing with property, action toxicity, fatal dose, detection, estimation of poisions, interpretation of the result of toxocological analysis
toxicology
chemical capable of producing a harmful reaction in a living organism.
toxicant (poison)
Any change that interferes with an organism’s normal functioning.
adverse effect
damage or kill living organisms because they react with cellular components to disrupt metabolic functions
toxins
was a scientist and physician who was born in Switzerland in 1493
Paracelsus
pioneered the use of chemicals and minerals in medicine. He is sometimes called the “father” of toxicology.
paracelsus
Prenatal alcohol abuse
fetal alcohol syndrom
mercury in fish
brain damage
lead in paint
brain damage
doixon posioning
facial scarring (chloracne)
small amount of botulinum toxin
prevents wrinkle (botox)
large amount of botulinum toxin
paralysis or death
amount, usually per unit body mass, of a toxicant to which an organism is exposed
dose
measured as milligrams of toxin per kilogram of body weight = mg/kg
dose
effect on an organism resulting from exposure to a toxicant
response
dose which is expected to kill 50% of the population in the particular group.
median lethal dose (LD50)
the dose that produces a desired response in 50% of the test population when pharmacological effects are plotted against dosage.
median effective dose (ED50)
important concept pertinent to the dose–response relationship is that of _______ dose, below which there is no response
threshold
Once a living organism has been exposed to a toxin, the compound must get into the body and to its target site in an active form in order to cause an ______
adverse effect
passive and facilitated diffusion, active transport
membrane barriers
defenses of body
membrane barriers, biotransformation enzymes, elimination mechanism
ADME
absorption, distribution, metabolisim, excretion
ability of a chemical to enter the blood (blood is in equilibrium with tissues)
absorption
readily absorb gases into the blood stream via the alveoli. (Large alveolar surface, high blood flow, and proximity of blood to alveolar air)
inhalation
absorption through GI tract stomach (acids), small intestine (long contact time, large surface area–villi; bases and transporters for others)
ingestion
absorption through epidermis (stratum corneum), then dermis; site and condition of skin
dermal
the process in which a chemical agent translocates throughout the body
distribution
Blood carries the agent to and from its site of action, storage depots, organs of transformation, and organs of elimination
distribution
Rate of distribution (rapid) dependent upon ____
blood flow, characteristics of toxicant (affinity for the tissue, and the partition coefficient)
Very lipophylic compounds (DDT) will store in fat. Rapid mobilization of the fat (starvation) can rapidly increase blood concentration
Storage in Adipose tissue