Adulteration

[L. adulteratio.]

1. The act of adulterating; corruption, or debasement (esp. of food or drink) by foreign mixture.

The shameless adulteration of the coin.

2. An adulterated state or product.

noun

The state of being contaminated: contamination, pollution, sophistication. See clean/dirty.

Mixing something impure with something genuine, or an inferior article with a superior one of the same kind.

Adulteration usually refers to mixing other matter of an inferior and sometimes harmful quality with food or drink intended to be sold. As a result of adulteration, food or drink becomes impure and unfit for human consumption. The federal Food and Drug Administration prohibits transportation of adulterated foods, drugs, and cosmetics in interstate commerce, as provided under the Food, Drug and Cosmetic Act (21 U.S.C.A. § 301 et seq. [1938]). State and local agencies, acting under the authority of local laws, do the same to ban the use of such impure goods within their borders.

The alteration, especially the debasement, of a substance by deliberately adding something not ordinarily a part of it.

The noun has 2 meanings:

Meaning #1: being mixed with extraneous material; the product of adultering
  Synonym: debasement

Meaning #2: the act of adulterating (especially the illicit substitution of one substance for another)