Ask a Question
Notify Me On Question Update
Email this Question
Would like to know how many drops in one ounce of water equals how many parts per million? Or quart ect.
Rate This FAQ
Parts Per Million (PPM)
A unit of concentration often used when measuring levels of pollutants in air, water, body fluids, etc. One ppm is 1 part in 1,000,000. The common unit mg/liter is equal to ppm. Four drops of ink in a 55-gallon barrel of water would produce an "ink concentration" of 1 ppm.
Parts Per Billion (PPB)
One part per billion is 1 part in 1,000,000,000. One drop of ink in one of the largest tanker trucks used to haul gasoline would represent 1 ppb.
The difference between 1 ppm and 1 ppb is important. A prestigious scientific journal recently reported the concentration of a substance as 0.5-1.5 ppm. The real value was 0.5-1.5 ppb. The difference between $1 and $1000!
Parts Per Trillion (PPT)
A unit of concentration used to measure vanishingly small levels of pollutants or contaminants in, for example, body fluids. One ppt is 1 part in 1,000,000,000,000. One drop of ink distributed through the water contained in a total of 4 of the 3-million-gallon reservoirs pictured would result in a final concentration of 1 ppt.
The remarkable advances in the sensitivity of modern analytical techniques makes it possible to detect some substances at the ppt level whose presence would not have been detected using earlier assay methods.
Submit Your Suggestion
Other Questions In This Topic
- I baked a German Chocolate cake yesterday that after baking and cooling slightly, you poke holes and put sweetened condensed milk in the holes, then you put a jar of butterscotch caramel topping on. I forgot to put it in the refrigerator before going to bed. Is is okay to eat? It doesn't have the Cool Whip on top yet.
- I just prepared chicken and spilled juices on the counter, how do I sanitize the countertop?
- How long can I keep leftovers in the refrigerator?
- What is being done to promote healthy eating in schools?
- Would you answer some questions about food irradation?
- How safe are herbal medicines?
- Is there a way to can something that has cooked eggs in it (like lemon curd) and store it safely, unrefridgerated, like bottled jam. (Not just storing it for 2-3 weeks in the fridge.)
- Will you please send me a recipe for pesto?