has been adulterating

• present perfect progressive

  present perfect progressive

  Used to describe an action that began in the past, has continued continuously, and is still in progress.

  of adulterate (3rd person singular).
  adulterate

  verb (used with object)

  to debase or make impure by adding inferior materials or elements; use cheaper, inferior, or less desirable goods in the production of (any professedly genuine article).

Related Words

• contaminate