The antonyms for the word "most purified" are impure, dirty, and contaminated. These words describe substances or materials that have not been properly cleaned or processed, and may contain harmful particles or bacteria. Impure substances may harm humans, animals, or the environment in various ways. Dirty environments can lead to the spread of diseases, and can negatively impact the health of those who come into contact with them. Contaminated water or air can also pose severe risks to the health and wellbeing of people, animals, and plants. It is essential to maintain a clean and healthy environment to ensure the safety and wellbeing of all living beings.