The term "became contaminated" can be described using a variety of antonyms that reflect the opposite of this negative condition. Antonyms for the word "contaminated" include "purified," "disinfected," "sterilized," and "cleansed." These words are often used in the context of water, food, and soil, where the removal of harmful substances is crucial for public health and safety. Other antonyms for "contaminated" may include "sanitized," "purged," "decontaminated," and "purified." Ultimately, the use of antonyms can provide a powerful tool for writers and communicators striving to describe complex environmental or health-related topics with accuracy and precision.