Any poisonous or deleterious substance added to any dairy product, except where the substance is required in production or cannot be avoided by good manufacturing practice, shall be deemed to be unsafe for purposes of the application of Subsection B of Section 10 [25-7A-10 N.M. Stat. Ann.] of the New Mexico Dairy Product Act; but when the substance is required or cannot be avoided, the board shall promulgate regulations limiting the quantity therein or thereon to such extent as the board finds necessary for the protection of public health, and any quantity exceeding the limits so fixed shall also be deemed to be unsafe for purposes of the application of Subsection B of Section 10 of the New Mexico Dairy Product Act. While such a regulation is in effect limiting the quantity of any such substance in the case of any dairy product, the dairy product shall not, by reason of bearing or containing any added amount of the substance, be considered to be adulterated within the meaning of Subsection A of Section 10 of the New Mexico Dairy Product Act. In determining the quantity of the added substance to be tolerated in or on different dairy products, the board shall take into account the extent to which the use of the substance is required or cannot be avoided in the production of each diary product and the other ways in which the consumer may be affected by the same or other poisonous or deleterious substances.