Unit 1 - Fundamentals of Toxicology Flashcards
Define poison.
Any solid, liquid, or gas that when introduced into a biological system can interfere with the life processes of the cells of the organism
What is a toxicant?
Essentially the same as a poison, but is less harsh
What is a toxin?
a poison that originates from a biological process
What is the difference between venomous and poisonous?
Venomous is a toxin that is delivered via a bite or a sting and poisonous is a poisoning that occurs via ingestion
Define toxic.
The adverse effects of poisons on living systems
Define toxicosis.
The disease state of being poisoned
Define toxicity.
The quantity or amount of toxicant that under a certain set of conditions will cause adverse effects
What is LD50?
The dosage where it is lethal to 50% of the population
What is ED50?
The dosage where the desired effect occurs to 50% of the population
What does NOEL stand for?
No Observed Effect Level
What does NOAEL stand for?
No Observed Adverse Effect Level
What does HNTD stand for?
Highest Non-Toxic Dose
What does MLD stand for?
Minimum Lethal Dose
Define dose.
The amount of toxicant that is received per animal
Define dosage.
The amount of toxicant per unit of animal mass or weight - time can also be included
What assumptions need to be made for the dose-response theory/model?
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
What big questions need to be asked regarding a suspect toxicity case?
What was the response? Where was the response? When was the response? Why was there a response? How did the response come about?
What should you always ask in a suspect toxicity case in regards to timing?
You should always ask if anything recent has occurred
Chronicity Index
CF = (1d(acute)LD50)/(90dLD50)
What does the 1 stand for?
1 - no cumulative effect
Chronicity Index
CF = (1d(acute)LD50)/(90dLD50)
What does the 90 stand for?
90 - absolute cumulative effect
What is a risk/hazard?
The likelihood of poisoning occurring under the conditions of usage
What factors affect response to a toxin?
Physiologic, environmental, nutritional status, health status, dose, physical nature of agent, solubility, route of exposure, and chemical interactions
What physiologic factors affect response to a toxin?
Species, breed, age, sex, pregnancy, and lactation
What environmental factors affect response to a toxin?
Season toxicosis, noxious vegetation, areas with loud noises, and water quality and quantity
What forms of chemical interactions can affect the response to a toxin?
Additive, synergistic, potentiation, and antagonism
1 mg/kg = ___ ppm
1
In order to change % to ppm, you need to move the decimal point ___ spaces to the right.
4 (so multiply by 10,000)
In order to to change ppm to %, you need to move the decimal point ____ spaces to the left.
4 (so divide by 10,000)
1 lb/acre = ___ mg chemical/kg BW
7
Express the following in ppm and in percent:
17 fluid ounces in 12 liters
1 L = 33.814 fl. oz
4.19%
41,900 ppm
Express the following in ppm and in percent:
0.25 quarts in 56 gallons
1 gallon = 4 qts
0.1116%
1116 ppm
Express the following in ppm and in percent:
9.27 grams in 1 kg
0.927%
9270 ppm
Express the following in ppm and in percent:
3 lb of molybdenium in 1000 bushel of soybeans
HINT: 1 bushel = 60 lb
0.005%
50 ppm
Express the following in ppm and in percent:
34 fluid ounces in 200 gallons
1 gallon = 128 fl. oz
0.1328%
1328 ppm
Express the following in ppm and in percent:
54 mg caffeine in 12 oz Mountain Dew
1 oz = 28349.5 mg
0.0152%
152 ppm
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?
- 00175%
- 5 ppm
Math:
(0. 07/100) x 50 = 0.035 lbs
0. 035/2000 lbs = 0.0000175
0. 0000175 x 100 = 0.00175%
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
~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
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?
~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
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?
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
