These chemicals are designated as those that are used in the manufacture of the controlled substances and are important to the manufacture of the substances.
hypophosphorous acid and its salts (including ammonium hypophosphite, calcium hypophosphite, iron hypophosphite, potassium hypophosphite, manganese hypophosphite, magnesium hypophosphite and sodium hypophosphite)[1][2]
Iodine, including elemental iodine crystals and chemical mixtures containing greater than 2.2% concentration of iodine (e.g., strong iodine tincture and Lugol's iodine)[3]
^[1] US DEA, "Final Rule: Changes in the Regulation of Iodine Crystals and Chemical Mixtures Containing Over 2.2 Percent Iodine," Federal Register, Volume 72, Number 126; July 2, 2007 (FR Doc E7-12736).