Calculations in Toxicology

Question 1

most common method of expressing concentrations in vet toxicology?

Answer 1

parts per million

Question 2

List important ppm relationships

Answer 2

1ppm = 1mg/kg
1ppm = 1ug/g

Question 3

what does 1 ppb =?

Answer 3

1ppb = 1ug/kg

Question 4

what does 1 ppt = ?

Answer 4

1 ppt = 1ng/kg

Question 5

Convert 1 ppm to a percentage. What is the general conversion rule?

Answer 5

1ppm = 0.0001%

To convert from ppm to %, move to the left 4 decimals. To convert % to ppm, move to the right 4 decimals.

Question 6

how much does 1g = in oz?

Answer 6

1g = 30 oz

Question 7

If you wanted to make a diluted solution from a concentrated stock solution, what equation would you use?

Answer 7

ml needed from stock = (% required dilution/% of the stock) x volume required in ml

Question 8

100g/ton = ____ ppm?

Answer 8

100g/ton = 110ppm

Question 9

You want a pig feed to contain 200 ppm arsanilic acid as a growth promoter. How many grams are needed per ton?

Answer 9

100g/ton = 110ppm
200/110 = Xg/ton/100g/ton
X = (200x100)/110
X = 182g/ton

Question 10

A feed additive for piglets was added at a concentration of 220ppm. How much is needed for 8 tons?

Answer 10

100g/ton = 110ppm
220/110 = Xg/ton/100g/ton
X = (220x100)/110
X = 200g/ton

X for 8 tons = 200x8 = 1600g = 1.6kg

Question 11

What equation would you use to look at toxicity of something in feed consumed daily?

Answer 11

Toxicity (mg/kg) = ppm in feed x % of feed consumed daily

Question 12

What are the assumptions regarding sprayed green forage?

Answer 12

every animal that ingests green forage that has been sprayed by a chemical at rate of 1lb/acre, will be exposed to 7mg per kg BW

1) good quality pasture produces 45g green forage per square foot
2) grazing animals consume 3% BW green forage