(Link) The easiest way to remember this is that it means milligrams per kilogram. If you have 100 milligrams of Vitamin E in a lotion and you have one kilogram or 1000 grams of lotion, you would have 100 ppm Vitamin E in that lotion.
The home of SwiftCraftyMonkey! Join Susan as she obsesses about cosmetic chemistry and other things (some possibly related to monkeys). Often strange, occasionally useful, and always worth a stop as a point of interest on your journey through the Intertron.
