1 Flashcards
(24 cards)
what are the 3 principles of toxicology?
dose response
hazard x exposure = risk
individual sensitivity
what is toxicology?
the study of the effects of chemical, biological, and physical agents on living organisms, particularly humans.
what is the internal dose?
amount of toxicant absorbed
only the amount that is absorbed is able to cause harm
what is the target organ dose?
amount that reaches the site at which effects occur
aka biologically effective dose
what is thalidomide?
its a teratogen
causes mutations in the embryo
mutagen and carcinogen
what is asbestos?
damage? effects?
a highly heat resistant fibrous material
damage is long term
effects can be malignant or non-malignant
how does lead toxicity affect the body?
it interferes with the action of calcium on cell functions and disrupts intracellular activities
can substitute for calcium and cross BBB
absorbed more by children
toxic effects of lead poisoning:
neurological effects
growth and development
renal diseases
fetal development
what are polychlorinated biphenyls?
chemically inert liquids, difficult to burn, electrical insulators
incineration of these form dibenzofurans
structure of dibenzofurans?
furan ring contains 5 atoms
chlorinated
toxicity of dioxins?
long term effects?
probs carcinogen
long term effects = reproduction, sexual development, congenital abnormalities + immune system disorders
what is a toxin?
poisonous substance produced by a biological organism
e.g. microbe, animal, plant
what is a poison?
substance that (taken into or formed within the organism) impairs the health of the organism and kills it
what is a toxic substance?
material / agent / chemical causing injury to living organisms as a result of physiochemical interactions
what is a toxicant?
preferred term for substance that is considered to be toxic under circumstances are likely to happen
what is venom?
an animal toxin used for self defence or predation
usually delivered by bite or sting
what is xenobiotic?
a foreign chemical substance found within an organism that is not naturally produced by organism
substances that are present in much higher concs than usual
what is bioacculumation?
when the rate of intake of substance is greater than excretion
dependent on size of molecules, solubility in water and lipids
what is biomagnification?
increased conc of a toxic chemical
something about high animals on food chain
what is the partition coefficient?
Kow = [S]octanol / [S]water
Kow values 0-3?
no bioconcentration potential
Kow values 4-7?
high bioconcentration potential
Kow values 7-8?
low bioconcentration potential
too strongly adsorbed to sediment
bioaccumulation = ?
bioconcentration + biomagnification
