Exam 1

Question 1

the study of harmful interactions between chemicals and biological systems

Answer 1

toxicology

Question 2

humans are exposed to chemicals both _______ and _______

Answer 2

deliberately (on purpose) and inadvertently (by accident)

Question 3

• experimentation is essential in the examination of responses to chemicals
• one should make a distinction between the therapeutic and toxic properties of chemicals
• these properties are often indistinguishable except by dose
• there is a degree of specificity of chemicals and their therapeutic or toxic effects (different cells affected differently)

Answer 3

Paracelsus

Question 4

used autopsy material and chemical analysis as legal proof of poisoning, forensic toxicology

Answer 4

Orfila

Question 5

studied mechanisms of action of morphine and strychnine, determined absorption and distribution of these compounds, toxicokinetics (movement of poison throughout the body)

Answer 5

Magendie

Question 6

toxic chemicals that are from natural (food, metals, minerals) or biological (from bacteria, fungi, etc) origin

Answer 6

toxins

Question 7

toxic chemicals that are synthetic - manufactured through chemical processes, man made

Answer 7

toxicants

Question 8

chemicals that are foreign to the organism

Answer 8

xenobiotics

Question 9

chemicals changed by the body

Answer 9

biotransformation

Question 10

the differences in susceptibility to toxic effects between different species or cell types

Answer 10

selective toxicity

Question 11

the dose that gets into the body

Answer 11

internal dose

Question 12

the dose at which there will be a response

Answer 12

biologically effective dose

Question 13

toxicity is relative depending on ___________ and __________

Answer 13

toxic properties, dose administered

Question 14

all interactions between chemicals and biological systems follow a ______-_____ relationship

Answer 14

dose-response

Question 15

dose below which there is no measurable effect, indicates the amount of exposure of a chemical without adverse effects

Answer 15

threshold

Question 16

dose at which response is 50%

Answer 16

EC50 or ED50

Question 17

death/lethality, determine % of animals or cells in a particular dosage that die (response), pathological lesions another example of this

Answer 17

all or none toxic responses

Question 18

greater amount of toxin means greater response (to an extent), level of biomarker, enzyme inhibition

Answer 18

graded toxic responses

Question 19

exposure to a combination of 2 or more chemicals is the sum of the expected responses

Answer 19

additive effect

Question 20

exposure to one chemical results in a response greater than the sum of the individual responses

Answer 20

synergistic effect

Question 21

exposure to one chemical results in the other chemical producing a response greater than if given alone

Answer 21

potentiation effect

Question 22

exposure to one chemical causes a decreased response to the other chemical

Answer 22

antagonism effect

Question 23

dosage which kills 50% of organisms in a group

Answer 23

LD50

Question 24

the more toxic a compound, the _______ the LD50

Answer 24

lower

Question 25

highest dose from a study that did not find any toxic , used to set exposure limit (acceptable daily intake for food additives and contaminants, threshold limit value for occupational exposure to industrial chemicals)

Answer 25

no observed adverse effect level (NOAEL)

Question 26

lowest dose at which a toxic effect has been observed

Answer 26

lowest observed effect level (LOAEL)

Question 27

type of exposure that is a single event or less than 24 hours, large dose size, no accumulation, toxic manifestations occur soon after the event

Answer 27

acute exposure

Question 28

type of exposure that is continuous or repeated, small or large dose size, accumulation present, toxic manifestations occur weeks to years later

Answer 28

chronic exposure

Question 29

cell death manifested as necrosis or apoptosis, death of hepatocytes by exposure to CCl4

Answer 29

direct toxic action - tissue lesions

Question 30

may cause death due to interference with some vital function

Answer 30

biochemical lesions

Question 31

hypersensitivity (immune system stimulated after individuals are exposed to chemicals or haptens which bind to or alter a protein) or allergic reactions

Answer 31

indirect immunotoxicity

Question 32

immunosuppression (direct injury to immune system, metals, PAHs, pesticides, drugs of abuse) and immunostimulation

Answer 32

direct immunotoxicity

Question 33

effect on the development of the embryo or fetus leading to a functional or structural abnormality, these compounds are often nontoxic to the mother but interfere in a specific way with the development of a particular stage

Answer 33

teratogenicity

Question 34

STOPPED AT GENETIC TOXICITY IN EXPOSURE AND RESPONSE SLIDES