Any added poisonous or deleterious substance, any food additive, any pesticide chemical in or on a raw agricultural commodity or any color additive, shall with respect to any particular use or intended use be deemed unsafe for the purpose of application of section 34A.02, clause (2), with respect to any food, unless there is in effect a rule pursuant to section 31.101 limiting the quantity of such substance, and the use or intended use of such substance conforms to the terms prescribed by such rule. While such rules relating to such substance are in effect, a food shall not, by reason of bearing or containing such substance in accordance with the rules, be considered adulterated within the meaning of section 34A.02, clause (1).