Chapter 1

Question 1

What is toxicology?

Answer 1

It is the science that deals with the harmful effects of substances on living organisms and assessment of the probability of their occurence

Question 2

What is food toxicology?

Answer 2

It is the study of the nature, properties, detection, and effects of toxic substances in food and their disease manifestation in humans

Question 3

What did paracelus say?

Answer 3

All substances are poison but it is the dose that makes the poison

Question 4

What is the major concept in toxicology that is based on what paracelus said known as now?

Answer 4

Dose response relationship

Question 5

What did paracelus studies reveal?

Answer 5

That a substance can be harmless or beneficial in a small dose however at higher doses it could become toxic

Question 6

Who is orfila(2) and what is his nationality

Answer 6

He is spaniah

He is a physician and the founder of toxicology

Question 7

What did orfila prepare?

Answer 7

He prepared a systematic correlation between the biological and physical properties od poison

Question 8

What did orfilla demonstrate?

Answer 8

He demonstrated the effects of poisons on specific organs by analyzing autopsy material for poisons and their associated tiasue damage

Question 9

Whats happening in the 20th century

Answer 9

There is a advanced level of understanding of toxicology

Question 10

How is the level of knowledge of toxic effects being revealed

Answer 10

Level of knowledge of the toxic effects on organs and cells is now being revealed at a molecular level

Question 11

What is being recognized concerning the toxic effects?

Answer 11

It has been recognized that all toxic effects are caused by changes in specific cellular molecules and biochemicals

Question 12

All toxins are toxicants and all toxicants are toxins
True or false
Why

Answer 12

False
All toxins are toxins but not all toxicants are toxins
Toxins are proteins / substances produced by living organisms / biological systems

Question 13

What is a toxicant? (4)

Answer 13

It is a chemical substance that can injure or kill a human, animal, or plant
It can cause physical or chemical damage
The effect duration may vary
It is used often in the context of man made substances

Question 14

What is a toxin? (3)

Answer 14

It is a specific substance produced by living organisms
It is often a protein
The effect is often immediate

Question 15

What is a poison? (2)

Answer 15

It is a toxicant that can cause immediate adverse effect

Usually small doses are sufficient

Question 16

What is a xenobiotic? (3)

Answer 16

It is any foreign substance to the body
It may be beneficial (pharmaceuticals) or it may be toxic (lead)
At small doses it may be non-toxic or even beneficial but as the dose increases it becomes to have a toxic or lethal effect

Question 17

What is the difference between systemic toxicant vs organ toxicant? (Give an example of each)

Answer 17

Systemic toxicant :
It affects the whole body or many organs / tissues rather than a specific site
such as potassium cyanide that interferes with oxygen utilization by the cells thus affecting all cells and organs

Organ toxicant:
Affects tissues or organs while not producing damage to the whole body
Such as benzene: is toxic only to the blood forming tissue
And lead which is toxic to three target organs: CNS, kidneys, and hematopoitic system

Question 18

What is the difference between toxicant and toxic agent?

Answer 18

Nothing

Toxicant is the scientific name of the toxic agent

Question 19

What is a toxic agent?

Answer 19

It is the substitute for the scientific term: toxicant

It is anything that may cause an adverse biological effect

Question 20

What are the different types of a toxic agent?

Answer 20

Biological ( snake venom )
Chemical ( cyanide )
Physical ( radiation )

Question 21

What are the different classifications of toxins / toxicants

Answer 21

Cyanide 
Heavy metals 
Animal toxin 
Food allergy 
Pesticides 
Plant toxins 
Mushroom toxins 
Microbial toxins

Question 22

What is toxicity defined as?

Answer 22

It is the ability of the toxicant to produce harmful effects on living organisms

Question 23

What factors influence the toxicity ? (4)

Answer 23

Intrinsic toxicity
Dose
Response of host
Exposure conditions