The antonyms for the word "more contaminating" include "purifying," "cleaning," and "sanitizing," among others. These words suggest the opposite of contamination and imply the removal or prevention of harmful substances, pathogens, or pollutants. Purifying implies the process of removing impurities or making something pure. Cleaning suggests the removal of dirt, germs, or unwanted substances. Sanitizing implies the use of chemicals or treatments to eliminate or reduce the number of microorganisms. All these antonyms are essential for maintaining hygiene, health, and safety, especially in areas prone to contamination, such as hospitals, laboratories, and food processing plants.