Unit 1 - Fundamentals of Toxicology

Question 1

Define poison.

Answer 1

Any solid, liquid, or gas that when introduced into a biological system can interfere with the life processes of the cells of the organism

Question 2

What is a toxicant?

Answer 2

Essentially the same as a poison, but is less harsh

Question 3

What is a toxin?

Answer 3

a poison that originates from a biological process

Question 4

What is the difference between venomous and poisonous?

Answer 4

Venomous is a toxin that is delivered via a bite or a sting and poisonous is a poisoning that occurs via ingestion

Question 5

Define toxic.

Answer 5

The adverse effects of poisons on living systems

Question 6

Define toxicosis.

Answer 6

The disease state of being poisoned

Question 7

Define toxicity.

Answer 7

The quantity or amount of toxicant that under a certain set of conditions will cause adverse effects

Question 8

What is LD50?

Answer 8

The dosage where it is lethal to 50% of the population

Question 9

What is ED50?

Answer 9

The dosage where the desired effect occurs to 50% of the population

Question 10

What does NOEL stand for?

Answer 10

No Observed Effect Level

Question 11

What does NOAEL stand for?

Answer 11

No Observed Adverse Effect Level

Question 12

What does HNTD stand for?

Answer 12

Highest Non-Toxic Dose

Question 13

What does MLD stand for?

Answer 13

Minimum Lethal Dose

Question 14

Define dose.

Answer 14

The amount of toxicant that is received per animal

Question 15

Define dosage.

Answer 15

The amount of toxicant per unit of animal mass or weight - time can also be included

Question 16

What assumptions need to be made for the dose-response theory/model?

Answer 16

Response is due to chemical administration or exposure
The magnitude of the responses is dose related
There is a quantifiable method of measuring the toxic endpoint

Question 17

What big questions need to be asked regarding a suspect toxicity case?

Answer 17

What was the response?
Where was the response?
When was the response?
Why was there a response?
How did the response come about?

Question 18

What should you always ask in a suspect toxicity case in regards to timing?

Answer 18

You should always ask if anything recent has occurred

Question 19

Chronicity Index
CF = (1d(acute)LD50)/(90dLD50)
What does the 1 stand for?

Answer 19

1 - no cumulative effect

Question 20

Chronicity Index
CF = (1d(acute)LD50)/(90dLD50)
What does the 90 stand for?

Answer 20

90 - absolute cumulative effect

Question 21

What is a risk/hazard?

Answer 21

The likelihood of poisoning occurring under the conditions of usage

Question 22

What factors affect response to a toxin?

Answer 22

Physiologic, environmental, nutritional status, health status, dose, physical nature of agent, solubility, route of exposure, and chemical interactions

Question 23

What physiologic factors affect response to a toxin?

Answer 23

Species, breed, age, sex, pregnancy, and lactation

Question 24

What environmental factors affect response to a toxin?

Answer 24

Season toxicosis, noxious vegetation, areas with loud noises, and water quality and quantity

Question 25

What forms of chemical interactions can affect the response to a toxin?

Answer 25

Additive, synergistic, potentiation, and antagonism

Question 26

1 mg/kg = ___ ppm

Answer 26

1

Question 27

In order to change % to ppm, you need to move the decimal point ___ spaces to the right.

Answer 27

4 (so multiply by 10,000)

Question 28

In order to to change ppm to %, you need to move the decimal point ____ spaces to the left.

Answer 28

4 (so divide by 10,000)

Question 29

1 lb/acre = ___ mg chemical/kg BW

Answer 29

7

Question 30

Express the following in ppm and in percent:
17 fluid ounces in 12 liters

1 L = 33.814 fl. oz

Answer 30

4.19%

41,900 ppm

Question 31

Express the following in ppm and in percent:
0.25 quarts in 56 gallons

1 gallon = 4 qts

Answer 31

0.1116%

1116 ppm

Question 32

Express the following in ppm and in percent:

9.27 grams in 1 kg

Answer 32

0.927%

9270 ppm

Question 33

Express the following in ppm and in percent:
3 lb of molybdenium in 1000 bushel of soybeans
HINT: 1 bushel = 60 lb

Answer 33

0.005%

50 ppm

Question 34

Express the following in ppm and in percent:
34 fluid ounces in 200 gallons

1 gallon = 128 fl. oz

Answer 34

0.1328%

1328 ppm

Question 35

Express the following in ppm and in percent:
54 mg caffeine in 12 oz Mountain Dew

1 oz = 28349.5 mg

Answer 35

0.0152%

152 ppm

Question 36

A sheep producer was sold a mineral premix containing Ca, Zn, Fe, Se and Cu to mix in his sheep
feed. The copper content of this premix was listed as 0.07%. If one 50 pound bag of this premix is
mixed in one ton of feed, how much would the copper level of the feed in ppm?

Answer 36

0. 00175%
1. 5 ppm

Math:

(0. 07/100) x 50 = 0.035 lbs
0. 035/2000 lbs = 0.0000175
0. 0000175 x 100 = 0.00175%

Question 37

The recommendation for treating gapeworms in Hungarian partridges is to mix fenbendazole in
the feed at the level of 200 ppm. Feed grade fenbendazole is available as an 8% premix. How many
ounces of this premix would it take to make 50 pounds of medicated feed?

1 oz = 28.53 g

Answer 37

~2 oz fenbendazole meal

Math:
Convert 50lbs into kg: 50/2.2 = 22.72 kg
Convert 200 ppm to mg/kg: 200 mg/kg
Set up equation: (22.72 kg) (200 mg/kg) = 0.08X
Solve for X
4545.454 mg = 0.08X
X = 56,818.175 mg -> 56.818 g
56.818/28.53 = 1.99

Question 38

Rampage® rodenticide is available in 30 gram packets. The active ingredient is 0.075%. What is the dosage (in mg/kg bwt) to a 44 pound dog that eats 25 of these packets?

Answer 38

~28 mg/kg

Math:
44 lbs/2.2 = 20 kg
30 g x 0.00075 = 0.0225 g
0.0225 x 1000 = 22.5 mg
22.5 mg x 25 packets = 562.5 mg (this would be the dose)
562.5 mg / 20 kg = 28.125 mg/kg

Question 39

The minimum toxic oral dose of Ruelene® in dairy calves is 50 mg/kg bwt. How many grams of a 25% Ruelene wettable powder would have to be given to a 100 pound calf to provide the 50 mg/kg bwt dosage?

Answer 39

9.08 g powder

Math:
100 lbs/2.2 = 45.5 kg
45.5 kg x 50 mg/kg = 2,270 mg
2,270 mg  is the toxic dose, however it is only 25% of the power, so you have to give 4x the amount of the powder in order to get the 2,270 mg dose.
2,270 mg x 4 (or /.25) = 9080 mg
9080 mg/ 1000 = 9.08 g