(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.
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(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.