1. 
2. 
[syn: uncontaminated, unpolluted]
WordNet (r) 3.0 (2006):
uncontaminated
    adj 1: not corrupted by contact or association; "there is no
           culture uncontaminated by contact with the outside world"
           [ant: contaminated]
    2: free from admixture with noxious elements; clean; "unpolluted
       streams"; "a contaminated lake" [syn: uncontaminated,
       unpolluted]
Moby Thesaurus II by Grady Ward, 1.0:
27 Moby Thesaurus words for "uncontaminated":
   absolute, beyond all praise, chaste, defectless, faultless,
   flawless, ideal, immaculate, impeccable, indefectible, indefective,
   infallible, irreproachable, just right, peerless, perfect, pure,
   sinless, spotless, stainless, taintless, unadulterated,
   unblemished, unfaultable, unmixed, unspotted, untainted