Intro and Physiochemical Properties

Question 1

Often the most informative classification of toxic agents is based on ___________

Answer 1

biochemical mode of action.

Question 2

Why are active ingredients mixed with inert ingredients in pesticide formulations?

Answer 2

To increase the ease of application and shelf-life.

Question 3

What is toxicology?

Answer 3

The study of the adverse effects of chemical agents on biological systems.

Question 4

What is acute toxicity?

Answer 4

short-term exposure of a single dose or repeated doses for periods of less than 24 hours.

Question 5

What is chronic toxicity?

Answer 5

repeated exposure for long periods of time.

Question 5

What is chronic toxicity?

Answer 5

epeated exposure for long periods of time.

Question 6

About how many insect species are considered pests that consume crops or spread diseases?

Answer 6

10,000

Question 7

what are the most commonly used pesticides?

Answer 7

Herbicides.

Question 8

How much global food production is estimated to be lost to pests?

Answer 8

20-40%

Question 9

What is the term for the highest dosage administered that does not produce toxic effects?

Answer 9

No Observable Effect Level (NOEL)

Question 10

What are the major factors that influence toxicity as it relates to exposure?

Answer 10

• Duration
• Frequency of Exposure
• Route of administration

Question 11

Which of the following are the three interrelated elements of toxicology?

Answer 11

• Biological system
• Chemical agent
• Deleterious response

Question 12

What is ionization largely dependent upon?

Answer 12

pH

Question 13

Two general characteristics of organochlorines/chlorinated hydrocarbons?

Answer 13

• Chemical stability
• Extreme lipophilicity and apolarity

Question 14

What is the definition of adsorption?

Answer 14

The adhesion of atoms, ions, or molecules to a surface.

Question 15

Which was the first successful neonicotinoid with a number of structural derivatives currently on the market?

Answer 15

Imidacloprid

Question 16

In an insecticide bioassay, why is it important to report the conditions (temperature, lighting, source of insects, etc.) of the experiment?

Answer 16

Because these conditions can impact the LD50 and LC50

Question 17

What is the definition of LD50?

Answer 17

The amount of poison per unit body weight which will kill 50% of the population being tested

Question 18

What are the three physical/chemical properties important to a compound’s toxicity?

Answer 18

• Solubility
• Adsorption
• Ionization

Question 19

In solubility, what determines if two substances are alike?

Answer 19

• Dipole moment
• Electron affinity
• Polarity

Question 20

What is responsible for getting a toxin to the target site and/or metabolic enzyme?

Answer 20

Physical properties

Question 21

What governs action at the site and metabolic stability?

Answer 21

Chemical properties

Question 22

Two subclasses of organophosphates?

Answer 22

• Phosphorothioates
• True phosphates

Question 23

What are the three assumptions regarding response?

Answer 23

1. A quantifiable method for measuring response is available
2. Response results from the chemical
3. Response is related to the dose administered

Question 24

what is a bioassay?

Answer 24

Any experiment in which a living organism is used as a test subject.