CFR › Title 21 › Part 582 › §582.526021 CFR §582.5260Verified against eCFR.gov as of June 20, 2026View official text on eCFR.gov ↗Copy link(a)Product. Copper gluconate.(b)Tolerance. This substance is generally recognized as safe for use at a level not exceeding 0.005 percent in accordance with good manufacturing or feeding practice.