Toxicology

Question 1

study of adverse effects of chemical, physical and biological agents

Answer 1

toxicology

Question 2

ability of the substance to cause injury

Answer 2

toxicity

Question 3

agent that is capable of producing deleterious effects in a biological system, seriously injuring function or producing death

Answer 3

poison

Question 4

“ward” version of poison

Answer 4

toxicant

Question 5

naturally occurring (plant/animal derived, endogenous to the organism)

Answer 5

toxins

Question 6

synthetically manufactured poisons

Answer 6

xenobiotics

Question 7

clinical state; overdose of drugs, medicaments, chemicals and biological substances

Answer 7

poisoning

Question 8

mechanisms of actions of chemicals in their toxic states

Answer 8

toxicodynamics

Question 9

adsorption, distribution, metabolism, excretion characteristics of substances in their toxic states

Answer 9

toxicokinetics

Question 10

involves toxicity testing of
chemicals, providing information for safety evaluation,
regulatory requirements (for example: chemical profile,
activity, how substances behave in different media)

Answer 10

descriptive toxicology

Question 11

concerns with identifying and
understanding mechanisms of action by which chemicals
exert toxic effects on living organisms, guide us on
treatment

Answer 11

Mechanistic Toxicology

Question 12

involves in decisions,
guidelines, and policies, on the basis of data provided by
descriptive and mechanistic toxicology, whether a
chemical poses a sufficiently low risk to be marketed for
a stated purpose (for example: tolerability, special
licenses to prescribe)

Answer 12

regulatory toxicology

Question 13

concerns with diseases caused by

or uniquely associated with toxic substances

Answer 13

Clinical Toxicology

Question 14

Clinical Toxicology plus Forensic
Pathology – concerns primarily with the medicolegal
aspects of the harmful effects of chemicals on humans
and animals. Does not only deal with toxicological cases
where the patient is already dead. (for example: collect
specimen and date for evidence)

Answer 14

Forensic Toxicology

Question 15

focuses on the impacts of
chemical pollutants in the environment on biological
organisms

Answer 15

Environmental toxicology

Question 16

study of the adverse effects
of agents that may be encountered by workers during the
course of their employment

Answer 16

Occupational Toxicology

Question 17

Factors affecting Responses to Toxic Agents

Answer 17

Agent
Envrionment
Individual Factors

Question 18

potential that injury will occur in a given situation

Answer 18

Risk

Question 19

intrinsic characteristic to cause harm to a

biological material

Answer 19

Toxicity

Question 20

amount of chemical that is available for

absorption.

Answer 20

Exposure

Question 21

explain R=TE

Answer 21

since toxicity of the substance is innate and constant, increase in exposure will cause increase in risk

Question 22

examples of Factors under “AGENT”

Answer 22

Chemical and Physical Properties of Substances

1. physical state
2. solubility
3. vapor pressure
4. vapor density
5. reactivity

Question 23

Physical State of substance: indications

Answer 23

liquid and gas are more easily absorbed in systemic circulation; more toxic

Question 24

Solubility of substance: indications

Answer 24

Lipophilic material & unionized
substances (easily absorbed)
»> more dangerous

Question 25

Vapor pressure: indication

Answer 25

>=1 mmHg, rapid volitzation, can travel faster, more reach

Question 26

Vapor density: indication

Answer 26

>1 - heavier than air - toxic substance will sink

Question 27

Reactivity: indications

Answer 27

Converted to a more toxic metabolite/compound Charged particles and reactive oxygen species are more deleterious.

Question 28

Talks about the Exposure Situation

Answer 28

Environment

Question 29

Factors under "ENVIRONMENT"

Answer 29

Duration Frequency Route dosage

Question 30

Types/variations of duration

Answer 30

Acute Exposure Subacute Exposure Subchronic Exposure Chronic Exposure

Question 31

exposure of substances with inhalational route

Answer 31

acute

Question 32

exposure of substances with oral route (usually)

Answer 32

subacute

Question 33

exposure which can result in cancer and transgenerational effects (i.e. endocrine)

Answer 33

chronic

Question 34

frequency of exposure is critical to ____

Answer 34

concentration levels of the substance in | biological fluids at target sites

Question 35

Order of effectiveness toxicity of different routes

Answer 35

Parenteral (Bioavailability= 100) > Inhalational > Intraperitoneal > Intramuscular > Subcutaneous > Intradermal > Oral and Dermal

Question 36

most critical factor in determining whether the intrinsic | potential of a substance will be expressed

Answer 36

Dosage

Question 37

example of agents which may trigger | transformation with one single exposure

Answer 37

Carcinogens, genotoxic agents

Question 38

examples of drugs which may not establish a dose-response relationship

Answer 38

Endocrine disruptors

Question 39

only a small amount (1 pg) of _____ can cause cancer

Answer 39

dioxin

Question 40

Examples of Individual Factors

Answer 40

``` Age sex genetic background nutritional status general health status ```

Question 41

paracetamol overdose leads to

Answer 41

liver problems

Question 42

isoniazid overdose leads to

Answer 42

inhibition of GABA synthesis -> seizures and B6 deficiency

Question 43

T/F The toxic action of a drug is an exaggeration of its therapeutic action

Answer 43

F; not necessarily; Some chemicals do not just exaggerate their actions in toxic states, they completely change their behavior

Question 44

example of a toxicant which may exert several mechanisms of toxic actions

Answer 44

lead - >breaks down sulfhydryl molecules of myelin sheaths -> neuropathy - > interferes with hemoglobin production by enzyme inhibition