The antonyms for the word "become tainted" are "improve," "refine," "purify," "cleanse," and "polish." When something becomes tainted, it means it has become corrupted, spoiled, or contaminated. To improve something means to make it better, and refine means to make it more precise. When something is purified, it means all impurities have been removed, while cleansing means to purify something to make it free from dirt or impurities. Lastly, when something is polished, it means it has been made shiny and attractive. These antonyms are essential in situations where one wants to replace the negative connotation associated with becoming tainted with something positive.