§ 346.
Any poisonous or deleterious substance added to any food, except where such substance is required in the production thereof or cannot be avoided by good manufacturing practice shall be deemed to be unsafe for purposes of the application of clause (2)(A) of section 342(a) of this title
([June 25, 1938, ch. 675, § 406], [52 Stat. 1049]; [Pub. L. 85–929, § 3(c)], Sept. 6, 1958, [72 Stat. 1785]; [Pub. L. 86–618, title I, § 103(a)(1)], July 12, 1960, [74 Stat. 398].)