(1) The department adopts 21 C.F.R. Part 589 – Substances prohibited from use in animal food or feed.

(2) For the purpose of RCW 15.53.902, the terms "poisonous substances" or "deleterious substances" include, but are not limited to, the following:

(a) Fluorine and any mineral or mineral mixture which is to be used directly for the feeding of domestic animals and in which the fluorine exceeds 0.20 percent for breeding and dairy cattle; 0.30 percent for slaughter cattle; 0.30 percent for sheep; 0.35 percent for lambs; 0.45 percent for swine; and 0.60 percent for poultry.

(b) Fluorine bearing ingredients when used in such amounts that they raise the fluorine content of the total ration (exclusive of roughage) above the following amounts: 0.004 percent for breeding and dairy cattle; 0.009 percent for slaughter cattle; 0.006 percent for sheep; 0.01 percent for lambs; 0.015 percent for swine and 0.03 percent for poultry.

(c) Fluorine bearing ingredients incorporated in any feed that is fed directly to cattle, sheep or goats consuming roughage (with or without) limited amounts of grain, that results in a daily fluorine intake in excess of 50 milligrams of fluorine per 100 pounds of body weight.

(d) Soybean meal, flakes or pellets or other vegetable meals, flakes or pellets which have been extracted with trichlorethylene or other chlorinated solvents.

(e) Sulfur dioxide, sulfurous acid, and salts of sulfurous acid when used in or on feeds or feed ingredients which are considered or reported to be a significant source of vitamin B1 (thiamine).

(3) When screenings are added to unmixed by-product feed, the screening must not contain any seed, pesticide, or other product that renders it adulterated within the meaning of RCW 15.53.902.

(4) All screenings or by-products of grains and seeds containing weed seeds, when used in commercial feed or sold as such to the ultimate consumer, shall be ground fine enough or otherwise treated to destroy the viability of such weed seeds so that the finished product contains no more than one viable prohibited noxious weed seed per pound and not more than twenty-five viable restricted noxious weed seeds per pound.

(5) For purposes of this rule, prohibited noxious weed seeds are those listed in WAC 16-301-045 (Prohibited noxious weed seeds) and restricted noxious weed seeds are those listed in WAC 16-301-050 (Restricted noxious weed seeds).

(6) Feed containing raw or unprocessed animal waste is adulterated under this chapter.

(7) In addition to the requirements in subsection (2) of this section, the terms "poisonous substances" or "deleterious substances" as used in RCW 15.53.902 include, but are not limited to, any ingredient that contains more than twenty parts per billion aflatoxin B1, B2, G1, G2, individually or in total.