Toxicology

Question 1

What is the basic definition of toxicology?

Answer 1

The study of adverse effects of chemicals or physical agents on living organism
The science of poisons

Question 2

Toxicology looks at the way…

Answer 2

Chemical interact with living beings and what changes they may cause or bring about

Question 3

Changes due to toxic conditions may range from;

Answer 3

Immediate and life threatening

Subtle changes that may not be recognized for month, years, or never

Question 4

What are some bodily levels toxic effects can occur in?

Answer 4

Biochemical, cellular and the whole organism

Question 5

What is a xenobiotic?

Answer 5

Any foreign substance in the body

Can produce toxic or beneficial results

Question 6

What makes something poisonous?

Answer 6

The dose

Question 7

What is a toxicant?

Answer 7

substance that produced biological effects

May be beneficial or adverse, chemical or physical, acute or chronic

Question 8

What is a toxin?

Answer 8

Specific proteins produced by living organisms

Most can cause immediate effects

Question 9

What are poisons?

Answer 9

Toxicants that cause immediate death or illness when given in very small doses

Question 10

What is a toxic agent?

Answer 10

Anything that can produce an adverse biological effects, but does not include agents produced by biological agents

Question 11

What is a specific organ toxin?

Answer 11

Agents which act on specific organs

Question 12

What is a systemic toxin?

Answer 12

Affects entire body

Question 13

What is an organic toxin?

Answer 13

Chemical derived from living organisms

Question 14

What are inorganic toxins?

Answer 14

Chemical not derived from living organisms

Question 15

What is the definition of a dose?

Answer 15

The amount of substance administered at one time

Question 16

What is an administered dose?

Answer 16

Quantity administered

Question 17

What is an absorbed does?

Answer 17

Amount that actual enters the body

Question 18

What is the total dose?

Answer 18

Sum of all administered doses

Question 19

What does fractionating a dose do?

Answer 19

Decreases the probability of toxicity

Question 20

What is the environmental unit?

Answer 20

The amount of a xenobiotic in a unit of the media

Question 21

What is dose-response?

Answer 21

How much of a does is needed to an effect to take place

Question 22

What is the threshold effect?

Answer 22

Establish the lowest dose where an effect occurs

Question 23

Describe the dose response for individual and for a population;

Answer 23

Wide variance for individual

Narrow range of response in population

Question 24

What is the top threshold for dose-response?

Answer 24

The level of toxicant at which the body can no longer detoxify itself

Question 25

How can damage occur in a toxic event?

Answer 25

``` Cell replacement (fibrosis) Damage to enzme system Disruption of protein synth Production of reactive cell chemical DNA damage ```

Question 26

How can xenobiotics have an indirect effect on toxicity?

Answer 26

Modification of essential biochemical functions Interference with nutrition Alteration of physiological function

Question 27

What factors influence toxicity?

Answer 27

``` Chemical activity Dosage Route of exposure Species Excretion Age Metabolism Sex Body distribution Absorption abnormalities Presence of other chemicals Form of substance Innate chemical activity of the substance ```

Question 28

What is one of the largest factors in toxicity?

Answer 28

Metabolism - Detoxification: less toxic - Bioactivation: more toxin

Question 29

If a toxin is lipid soluble what does its distribution look like?

Answer 29

Wide

Question 30

What are major avenues or toxin spread?

Answer 30

Blood and lymph

Question 31

What is the significance of the exposure route of a toxin?

Answer 31

Some substances are more toxin by one route than another

Question 32

What is the general rule for toxin route exposure?

Answer 32

Ingested chemicals go to liver and get detoxified | Inhaled chemicals go straight to the blood stream and distribute before getting to the liver

Question 33

Site and range of excretion for toxin follow this pattern in general;

Answer 33

Kidney > GI tract > lungs

Question 34

What does it mean when a chemical interaction is additive (additivity)?

Answer 34

A combination of two or more chemical is the sum of the expected individual response (most common)

Question 35

What does it mean when a chemical interaction has antagonism?

Answer 35

Physiological: effect of one drug can be lessened or reversed by another Chemical: the effect of one can be reduced by another (binding) Disposition: one is absorbed by another (charcoal) Receptor: one displaces another from receptor site

Question 36

When is a chemical interaction has potentiation what does that mean?

Answer 36

One chemical without a specific effect makes another toxic | carbon tetrachloride + alcohol

Question 37

What does it mean when a chemical interaction is synergistic?

Answer 37

One chemical may drastically inc the effect of another | cigarette smoke and radon

Question 38

Why are federal agencies involved in toxicity testing?

Answer 38

Because there have been really horrible past disasters (especially with birth defects)

Question 39

What are the federal agencies that are involved in toxicity testing?

Answer 39

FDA, EPA, CPSC and OSHA

Question 40

What are the four steps of risk assessment of toxins?

Answer 40

1. Hazard identification (characterization of toxic effects) 2. Dose-response assessment (relationship of doses to adverse effects) 3. Exposure assessment (estimate intensity, duration and frequency of exposure) 4. Risk characterization (estimate of effect under various condition of exposure)

Question 41

What are the three methods to toxicity testing?

Answer 41

- Study and observe during normal or accidental exposures - Experimental animal studies - Cellular studies

Question 42

What are some common adverse drug reactions (ADR)?

Answer 42

Overdose of BP meds ASA (anti-inflam) Antihistamine

Question 43

What are some cause effects of some med?

Answer 43

Fetal abnormalities Stroke and MI Insomina Spontaneous achilles tendon rupture

Question 44

What is an idosyncratic reaction?

Answer 44

Unpredictable, unexpected and scary reaction